DCT100 Laboratory Module

Transcription

Laboratory Module
DCT100/2
Basic Engineering
Skill
Engineering Centre
Universiti Malaysia Perlis
DCT100/2
Basic Engineering
Skill
Sharulnizam Bin Mohd Mukhtar
Mahammad Akmal Bin Saad
Sabri Bin Zakaria
Mohd Nazri Bin Abu Bakar
Wan Mohd Faizal Bin Wan Nik
Nurulazmi Bin Abd. Rahman
__________________________________________
Engineering Centre
Basic
Computer
DCT 100 – Basic Engineering Skill
Laboratory Module
BASIC COMPUTER
1.0 OBJECTIVE:
1.1 To learn the basic component of computer
1.2 To learn computer assembly
1.3 To learn the operating system and configuration.
2. INTRODUCTION
2.1 Introduction to basic component of computer
When you mention the word "technology", most people think about computers.
Virtually every facet of our lives has some computerized component. The appliances
in our homes have microprocessors built into them, as do our televisions. Even our
cars have a computer. But the computer that everyone thinks of first is typically the
personal computer, or PC.
A PC is a general purpose tool built around a microprocessor. It has lots of different
parts -- memory, a hard disk, a modem, etc. -- that work together. "General purpose"
means that you can do many different things with a PC. You can use it to type
documents, send e-mail, browse the Web and play games.
In this course, we will talk about PCs in the general sense and all the different parts
that go into them. You will learn about the various components and how they work
together in a basic operating session. You'll also find out what the future may hold
for these machines.
Let's take a look at the main components of a typical desktop computer
1. Central processing unit (CPU) - The microprocessor "brain" of the computer
system is called the central processing unit. Everything that a computer does
is overseen by the
CPU.
Image 1: Processor
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2. Memory - This is very fast storage used to hold data. It has to be fast
because it connects directly to the microprocessor. There are several specific
types of memory in a computer:
• Random-access memory (RAM) - Used to temporarily store
information that the computer is currently working with
Image 2: RAM
•
Read-only memory (ROM) - A permanent type of memory storage
used by the computer for important data that does not change
• Basic input/output system (BIOS) - A type of ROM that is used by
the computer to establish basic communication when the computer is
first turned on
• Virtual memory - Space on a hard disk used to temporarily store data
and swap it in and out of RAM as needed
3. Motherboard - This is the main circuit board that all of the other internal
components connect to. The CPU and memory are usually on the
motherboard. Other systems may be found directly on the motherboard or
connected to it through a secondary connection. For example, a sound card
can be built into the motherboard or connected through PCI.
Image 3: Motherboard
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4. Power supply - An electrical transformer regulates the electricity used by the
computer.
Image 5: Power supply
5. Hard disk - This is large-capacity permanent storage used to hold information
such as programs and documents.
Image 6: Hard disk drive
6. Operating system - This is the basic software that allows the user to
interface with the computer.
7. Integrated Drive Electronics (IDE) Controller - This is the primary interface
for the hard drive, CD-ROM and floppy disk drive.
8. Peripheral Component Interconnect (PCI) Bus - The most common way to
connect additional components to the computer, PCI uses a series of slots
on the motherboard that PCI cards plug into.
9. SCSI - Pronounced "scuzzy," the small computer system interface is a
method of adding additional devices, such as hard drives or scanners, to the
computer.
10. AGP - Accelerated Graphics Port is a very high-speed connection used by
the graphics card to interface with the computer.
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11. Sound card - This is used by the computer to record and play audio by
converting analog sound into digital information and back again.
Image 7: Sound card
12. Graphics card - This translates image data from the computer into a format
that can be displayed by the monitor.
Connections: Input/Output
No matter how powerful the components inside your computer are, you need a
way to interact with them. This interaction is called input/output (I/O). The most
common types of I/O in PCs are:
1. Monitor - The monitor is the primary device for displaying information from
the computer.
Image 8: Flat monitor and CRT monitor
2. Keyboard - The keyboard is the primary device for entering information into
the computer.
Image 9: Keyboard
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3. Mouse - The mouse is the primary device for navigating and interacting with
the computer
Image 10: Mouse
4. Removable storage - Removable storage devices allow you to add new
information to your computer very easily, as well as save information that you
want to carry to a different location.
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Floppy disk - The most common form of removable storage, floppy
disks are extremely inexpensive and easy to save information to.
CD-ROM - CD-ROM (compact disc, read-only memory) is a popular
form of distribution of commercial software. Many systems now offer
CD-R (recordable) and CD-RW (rewritable), which can also record.
Flash memory - Based on a type of ROM called electrically erasable
programmable read-only memory (EEPROM), Flash memory
provides fast, permanent storage. CompactFlash, SmartMedia and
PCMCIA cards are all types of Flash memory.
DVD-ROM - DVD-ROM (digital versatile disc, read-only memory) is
similar to CD-ROM but is capable of holding much more information.
Connections: Ports
•
Parallel - This port is commonly used to connect a printer.
Image 11: Parallel port
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Serial - This port is typically used to connect an external modem.
Image 12: Serial port
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Universal Serial Bus (USB) - Quickly becoming the most popular external
connection, USB ports offer power and versatility and are incredibly easy to
use.
Image 13: USB port
Connections: Internet/Network
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Modem - This is the standard method of connecting to the Internet.
Local area network (LAN) card - This is used by many computers,
particularly those in an Ethernet office network, to connected to each other.
Cable modem - Some people now use the cable-television system in their
home to connect to the Internet.
Digital Subscriber Line (DSL) modem - This is a high-speed connection
that works over a standard telephone line.
Very high bit-rate DSL (VDSL) modem - A newer variation of DSL, VDSL
requires that your phone line have fiber-optic cables.
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Questions:1.
2.
3.
4.
5.
6.
What is RAM? Explain the uses of RAM.
What do you understand about CPU?
Discuss the significance of computer.
Who are Intel, Microsoft, Oracle, and Google?
There is several company manufacture RAM. List down three of them.
Do you own a computer? Write about your computer (example: how much
the speed, RAM, Hard disk etc.)
7. Do you have pen drive? What do you understand about your pen drive?
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COMPUTER ASSEMBLY
3.0 TOOLS REQUIRED
Tool required
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Screwdriver
PC Case
Floppy Disk Drive
Hard Drive
CD-ROM Drive
Processor
Processor Cooling Fan
Motherboard
Memory Modules
Power Supply
Software Required
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System Disk
Device Drivers (these usually come with the hardware above)
Operating System
Cables and Miscellaneous
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Drive cables
Motherboard spacers (usually come with the motherboard, but are used to
space the motherboard up off the mounting plate)
Screws
Power cords
CPU Cooling Compound
3.1 FIND A CLEAN AND STATIC FREE WORK ENVIRONMENT
Some examples of this type of environment could be:
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In the garage on the workbench
On the kitchen counter
At the dining room table
At your desk if it's not on carpet
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It is possible to safely build a computer on carpet but we would not
recommend it, especially for the first time builder. You just want to be as
safe as possible and take as many precautions as you can to prevent
damaging your new computer.
3.2 OPEN AND PREPARE THE CASE
Most cases available allow access to the inside through their side panels. Some
used to require you to take the entire sides and top off but since making your own
custom computer is becoming more popular, the case manufacturers decided to
make things easier. If your case doesn't come off in the described manner, just refer
to the manual it comes with, or do some experimenting to find out how to open it up.
The following sets of pictures show two different cases illustrating how they can
either come off in one piece, or have the side panels removed.
Removing the Case as a Whole
Image 1: Casing
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Image 2: Screw out
Image 3: Open the casing
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Image 4: Look for power supply
Once the case is open, make sure you locate the power supply if it was supposed to
come with one. If it already has a power supply, skip to the part of this step entitled "
Installing the Risers. " Before you do that however, make sure your case comes
with a bag of screws. These will be needed throughout the construction of your
computer.
Installing the Power Supply:
Most power supplies are a standard size and should fit nicely in the case at the
top. Just make sure the fan is unobstructed and the screw holes in the power supply
line up with the screw holes in the case. It may help to lay the case on its side while
screwing in the power supply
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Image 5: Put the power supply into casing
Image 6: positioned the power supply
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Image 7: Screw the power supply
Image 8: Screw the power supply tighten
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Installing the Risers:
Image 9: Risers
Locate the bag of screws that came with your case and take out the motherboard
risers. They will either be plastic or metal. Either type will work, and in some cases
you can use both. Right is an example of a typical metal riser.
You will need as many risers as there are holes in the motherboard. So carefully
take your motherboard out of its anti-static bag and place it on that bag. Orient the
motherboard as if you were going to place it in the case by making sure the
connecting ports on the motherboard (where you connect the keyboard, mouse,
USB components, etc) are facing out the back of the case. Count the holes in the
motherboard and see where they line up on the inside of the case. It may be a good
idea to mark these holes in the case with a highlighter or marker so it's easier to
remember where to install the risers.
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Image 10: Installing risers
Next simply screw the risers into place, as seen above, making sure they're tight. If
the motherboard happens to have some extra holes where there are no holes lining
up with them in the case, just pop in some of the plastic risers with the pointy part of
the riser pointing through the face of the motherboard. What this does is prevent the
metal of the case from touching of the electronic components on the underside of
the motherboard.
Once the risers are installed, you can get the front of the case ready for the drives.
3.3 INSTALL THE MOTHERBOARD
This is where a delicate hand will be needed.
When installing most computer parts, and especially the motherboard,
you must remember that you shouldn't force anything in, but you can't be
too timid as to not apply enough pressure to make things fit. Since all
these computer parts must be universal fitting, the chances of something
being just a little off here or there is expected and should not be
interpreted as not being able to fit. There's a certain way of maneuvering
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the motherboard in that allows it to sort of lock into place just before you
screw it in.
Place it in the case:
Touch the case! Remember, if you're not using a static wristband then make
sure you are always touching the case while handling electronic components
Take the motherboard back out of the bag and double check to make
sure the risers you installed line up with the holes in the motherboard and
the rectangular plate on the back of the case lines up with the ports on
the motherboard. The best way to maneuver the motherboard in there is
to have the case on it's side and lower the motherboard slightly at an
angle, with the ports going in first. Push the motherboard against the
rectangular port plate so that it's snug, then lower the rest of the
motherboard down. If done correctly the holes in the motherboard
should line up with the risers more or less. If they don't, then try doing
this lowering step a couple times or check to see if there are any
obstructions between the motherboard and case.
Image 11: Installing motherboard
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3.4 INSTALL THE PROCESSOR (CPU-CENTRAL PROCESSING UNIT)
Socket processor installation:
This installation is a little more difficult, but all you have to do is be careful that you
don't bend any pins and make sure you orient the processor correctly to fit in the
socket.
Image 12: Socket for processor
When you look down at the motherboard you will see a place for the processor to
go that looks like the picture on the right. If you look closely, you can see that one
of the corners of the socket (the top right corner) is missing a hole. That's so it
matches up with the processor and the processor can fit into the socket in only one
way. You should also see a small lever towards the top of the socket that if pushed
down and away from the socket, will lift up and shift the top part of the socket one
way. This will be used to secure the processor in place.
Once the lever is up you're ready to put the processor in place. Just make sure
you find the corner on the processor that is missing a pin, and place the
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Image 13: Heat sink
processor down into the socket. If all the pins line up then it should plug in there
fairly easily, although it could take just a little gentle moving around to find it's
place. Once you are positive that the pins are lined up and in their place, push down
on the processor and push the lever down and lock it into place. Once the CPU is
secure, you'll need to install the heatsink. A heatsink (pictured to the right) is a metal
structure that is used to dissipate heat generated by the processor.
Depending on the type of fan you have will determine how it is installed. Most
likely there will be instructions that come with it so please consult those for specific
directions on how to secure it. Most likely you will simply hook the fan over the
heatsink and processor, connecting it to the plastic socket holding the processor in.
Once the fan is installed, make sure you connect the wire that powers the fan as
seen above. The fan does you no good unless it's plugged in!
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Install the processor:
Image 14: Install the processor
Once the heatsink and fan are attached to the processor, just slide the processor
into place in its slot with the fan and heatsink pointing towards the front of the case
as pictured on the right.
Once the fan, heatsink, and CPU are installed, make sure you connect the wire that
powers the fan as seen above. The fan does you no good unless it's plugged in!
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3.5 INSTALL THE RAM
RAM installation is very easy, and very foolproof.
Image 15: RAM socket
As you look at the slots on your motherboard, notice that there are notches that
prevent you from installing the RAM backwards or upside down. The gold plated
edge of the RAM is the part that will be going into the slot itself.
To determine which slots the memory will go into, please consult your
motherboard manual. Each motherboard may be different as to how many slots
need to be taken, and in which order. Not following the manual instructions can
cause a big headache as illustrated in the example below.
Once you establish which slots need to be filled up and in what sequence, it's just a
matter of popping the memory into place.
Those white tabs at the ends of each slot will need to be opened away from the
slot itself. Those are what hold the memory into place. Once those are opened, just
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determine which way the RAM should fit in there, making sure the notches on the
gold plated side match up with the notches in the RAM slot. Then firmly press down
until those white tabs pop back in towards the slot, locking the RAM into
place. Don't be afraid to use a little pressure, but make sure everything is lined up
correctly before you do.
3.6 INSTALL THE HARD DRIVE
This will probably be one of the most difficult steps of the installation, but luckily,
as long as you comprehend everything and find a nice place for the hard drive then it
will go by very easily.
In this step we explain the function of the IDE Cable, how many devices can be
attached, and the Master/Slave relationship between two devices on one
cable. After you learn that you'll be able to install the hard drive and you'll also be
ready to install the other drives later on.
Image 16: IDE ribbon cable
The IDE Ribbon Cable:
The IDE Cable, pictured above, allows you to attach certain devices to the
motherboard. Some of the most common devices that are attached using these
cables are the CD/DVD drive, Hard Drive, and Iomega Zip or Jaz drives. It does
matter which devices are on the same cable, and which are connected to the
primary plug on the motherboard so read closely.
The motherboard will have two plugs that the IDE cable can connect to. Each
IDE cable has 3 connectors, one for the motherboard (pictured above in blue), and
two for any devices such as the CD/DVD drive, hard drive, etc. Also, all devices will
have the option of being the Master or Slave . What this means is that the master
will have priority over the slave for using the processor. If this is at all confusing
please refer to this Website for a more in depth explanation.
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Now that you know all that, let's explain which devices should have first
priority.
Since your hard drive is where you run all your programs from and store all your
important information, it should be set as the master and put on the primary
connector on the motherboard. Depending on the brand of your hard drive
(hopefully Western Digital), you'll need to refer to the manual to see what the jumper
setting should be. That depends on one thing, whether there is going to be another
device on that same cable. If there is, then the jumper is usually in the middle, if not,
the jumper is usually completely removed.
Look at the picture below to see the rows of pins under the "jumper setting"
box. There are two rows of six pins, this is where you will make the setting. Again,
refer to the manual that came with your hard drive since the settings can differ
between companies as well as models.
Image 17: Several type of port
With a standard motherboard this makes a total of 4 devices you can connect. If
you plan on having two CD or DVD drives then you will definitely want to attach
those on separate IDE cables to reduce any problems that could be encountered
while copying a CD.
Example:
So for a hypothetical example let's say you have a DVD burner, a spare CD drive, a
hard drive, and a Zip drive. The hard drive will be the master on the primary IDE
cable with the spare CD drive as the slave. This is the only option because the DVD
burner, being a higher end drive, would need priority in having access to the
processor, thus making it the master on the secondary IDE cable. So on the
secondary IDE cable would be the master, DVD burner, and the slave, the Zip
drive. Refer to the diagram below for a visual explanation.
Once you understand this, the only limitation is the physical distance between
devices and making sure the IDE cable will reach every device; that's why it pays to
plan out where you will be installing everything.
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Installing the Hard Drive:
Ok, now that you know all that, you'll need to find a good place to put your hard
drive. Keep in mind that the IDE cable is only so long, so it would be a good idea to
measure the distances between the two devices that will be on the same cable,
making sure everything will fit.
Since the hard drive is where all the information on a computer is stored it will be
used quite a bit and therefore will generate a good amount of heat. That's why it's
important to place it where it will
Image 18: Installing hard drive
get plenty of ventilation. If you look at the open case on the right, you'll notice the
rack on the right side where all the devices will be secured. The hard drive typically
goes on the bottom of this rack to provide plenty of ventilation. If you have two hard
drives, make sure not to put them right on top of each other, leave at least an inch of
space between the two.
The best way to situate the hard drive in there is to orient it so the pins and
plug are facing towards the inside of the computer. Take your hard drive and
slide it towards the front of the computer into the rack I mentioned. Now just
make sure that the holes in the side of the hard drive align with the holes in
the rack. Hard drives usually require large thread screws but if those don't
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seem to go in very easily, then just try small thread screws to see if that works
better. Use 2 screws to secure the side of the hard drive that's facing you. It
isn't usually necessary to use 2 screws on the other side as well, but you can
if you want.
3.7 INSTALL THE VIDEO CARD
It's all downhill from here!
Installing the cards and double checking everything is all that's needed before you
can turn the computer on for the first time.
Image 19: Video card
Locate your video card, it's the one with a blue connector on the back and looks
like the picture on the right. Since video cards use more resources and power of all
the other cards in your computer, they have their own special slot closer to the
processor. Typically this slot is brown in color and is slightly offset from the other
PCI slots.
The slot you'll be inserting the video card into is called an AGP slot . The
process for inserting this card is the same as all the other cards aside from the fact
that it goes in a different kind of slot.
To install:
sure you are always touching the case while handling electronic components.
Simply place the card over the AGP slot on the motherboard and settle it in
slowly. There are different kinds of AGP slots so make sure that your
video card fits in this kind. If your motherboard and video card are fairly
recent, then you should have no problems with this. If your card lines up
but doesn't seem to fit, then double check to see if the notches in the
card line up with the ones on the motherboard. If they don't, then it
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looks like you may have to return your video card for one that is
compatible with your motherboard. Consult your motherboard manual
for details on what sort of AGP cards it supports, then buy a video card
accordingly.
Image 20: Installing video card
Make sure the card is seated well in the slot by pushing down on the edge of it
along its length. It should feel secure in there, and the back end of the card should
be lined up with the empty slot on the back of the computer.
Image 21: Installing video card
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If everything goes well, you can go ahead and finish your first card installation by
securing it with a screw. Locate the bag of screws that came with your case and find
a screw with Large Threads. Use this screw to secure the card in the location
illustrated by the picture on the right.
3.8 INSTALL THE CD OR DVD DRIVE
Typically the CD/DVD drive goes in the very top bay of the computer case, but
before you do that, make sure the IDE cable is long enough to connect both devices
that will be on that cable. If the CD/DVD drive is going to be the only device, then
this won't be a problem.
Installing the CD/DVD drive:
Since with most cases it would be nearly impossible to slide the CD/DVD drive in
from the inside, we'll focus on installing it through the front of the case.
Make sure you've removed any plastic panels or metal tabs that might be covering
up the extra bays inside the case. If you haven't already done this, then refer to
Step 2 (Preparing the case) .
One more thing you should do before putting the drive in is to check the jumper
settings to make sure they coincide with the setup you've determined.
Image 22: Installing CD or DVD drive
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When you're ready to physically install the drive , just slide it into the bay you've
selected for it. Everything should go smoothly, if it doesn't then you should check for
any obstructions that may be blocking it.
Image 23: Screw the DVD or CD drive
Once the front of the drive is flush with the case you're ready to secure it with
screws. Sometimes the CD/DVD drives come with a bag of four small screws. Don't
worry if it didn't since you can go ahead and use the small thread screws that came
with your case. If the cover of your case doesn't come off in one piece, but rather
has two panels that slide off (as is typical), then go ahead and take the panel off the
other side if you already haven't. This is necessary to access the screw holes on the
other side of the drive. It's a good idea to use all four screw holes available, unlike
the hard drive installation, because you will be pushing the button on CD/DVD drive
quite often, and the more secure it is the less chance there is of it coming
loose. Sometimes a CD or DVD drive will have eight screw holes available. Four
screws are plenty and using eight screws would just be overkill.
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Image 24: Install the floppy drive
Install the Floppy Drive:
We won't go into as much detail on this part since it basically follows the same
pattern as the CD/DVD drive did. The only difference is that the bay is smaller. Find
the floppy bay and slide the floppy drive in making sure the front of it is flush with the
front of the case. Sometimes cases have a hidden bay where you will need to load
the floppy drive in from the inside of the case. Secure it in with some screws and
move on to the next step.
Once you secure the drive with all four screws you're ready to connect all the
devices with the IDE cable.
Connect the devices:
Now that you have all the devices in the computer, you're ready to connect all of
them.
Refer once again to the diagram to see which devices you want to connect
together. Make sure your master and slave settings are correct. Remember to
locate the primary and secondary IDE plugs on the motherboard. You'll want the
hard drive to be on the primary. Once you're sure that you know how everything is
going to be set up, go ahead and take the IDE cables that came with your hard drive
or CD/DVD drive and connect the devices to the motherboard. These cables are
keyed so they can only go in one way. The only exception to that rule is the floppy
cable.
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Below: IDE1 is the Primary IDE plug
Note the number 1 below the bottom left corner of IDE1
That should coincide with where the red wire on the IDE cable goes.
Image 25: IDE 1
Below: The same concept but slightly different
Notice the white corner on the bottom left of each plug. This signifies Pin 1
Image 26: IDE port
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The floppy cable is usually keyed but can sometimes go in either way. The best
thing to do is look at where Pin 1 is (as seen above) on both the floppy drive and the
motherboard. Also, remember that the part of the floppy cable that twists goes
closest to the floppy drive itself. If you still aren't sure as to how to connect the
floppy drive, just ask a question on the Message Boards.
3.9 CONNECT THE CASE WIRES TO THE MOTHERBOARD
This is a step where it pays to check and double check your work.
Often times a computer's initial problems can be attributed to not connecting
everything correctly. In this section we will go through each and every possible
connection you will make in your computer to get it up and running.
Keep in mind:
You want to make sure that none of the wires obstruct the movement of the
processor fan. We have done this before and it WILL cause the processor to
overheat, halt the computer, and possibly damage the processor itself. Zip
ties are a good way to clean up the inside of the computer and allow you to
bundle the wires together.
Connect the power wires:
The power wires are the most foolproof wires that you will be connecting in this
part. Each connector coming from your power supply is made so that it can only
attach in the correct manner.
Image 27: Motherboard connection
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Pictured above, this connector has the most wires leading to the power
supply. Locate the plug on the motherboard and plug it in. That's it. It will only go in
one way, unless you force it of course, and once it's in it will be secured by a clip that
you can see in the picture on the right. You won't be able to pull it back out without
pressing this clip and lifting at the same time. To make sure it's secure go ahead
and try lightly pulling on the connector without pressing the clip. If it stays seated,
then you're done with this connector.
Hard Drive, CD/DVD, and Zip/Jaz Drives:
The connectors for these devices have four wires stemming from them (pictured
right). If you look closely you'll see that two of the four corners have notches in
them. This is to ensure that the connectors only go in one way. Before actually
connecting each drive you should make sure that each connector will be able to
reach that drive. If you have a couple of short wires and more devices that are a
further distance away from the power supply, then you may need to rearrange some
of your devices so they all are able to have a power connector. Connecting it is
simple, just make sure it's seated properly and is snug enough where some force is
needed to pull it out again.
Image 28: Connector for hard drive, CD,DVD
Floppy Drive:
The floppy drive power connector is much smaller and has only four wires coming
from it. It used to be easy to connect these connectors backwards but now they are
keyed to fit only one way like the rest of the power connectors stemming from the
power supply.
Other Power Connections:
Some motherboards have other places that may or may not require a power
connector to be connected. Some of these seem extraneous but can really help the
performance of the computer. First, look at your motherboard manual to see if you
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have any of these connections. If you do then make sure you have the appropriate
power connectors stemming from the power supply. Computer building is becoming
much more "plug and play" so chances are if a connector looks like it will fit then it
probably will. Of course, when in doubt, look it up in your manual.
Some places to look on the motherboard would be somewhere else near the
processor, and somewhere near the AGP slot. With video cards becoming more
advanced, many may need that extra boost of power from the power supply to
perform at full potential. Another place that may require an extra boost of power is
near the processor somewhere on the motherboard. Before plugging any of the
extra power wires to the motherboard, make sure you check the manual to see what
they are for sure.
Front Panel Connector
This connector makes sure the buttons and lights on the front of your panel know
how to work. It also powers the speaker that makes that "beep" sound when you
turn on your computer. Each motherboard may be different but the instructions will
look very similar to what is shown below.
Image 29: Connecting front panel connector
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Laboratory Module
Image 30: Different type of wire
It is very important to consult your manual to make sure you make all the appropriate
connections. One thing to keep in mind, the wires leading from the front of your
case will have black connectors on the ends of them that look like the picture on the
right. Each of these connectors has a wire that holds the positive charge. If you
look above, for example at the four orange pins on the top illustration that signifies
the speaker, you'll see that one end of that row has a plus sign next to it.
Image 31: Connector
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Laboratory Module
To locate the wire that has the positive charge on the connector, find the tiny triangle
on that connector, as pictured to the above. This is where patience and small hands
come into very good use. Just take your time and make sure you consult the
manual for all your connections.
USB/Firewire/Audio Connections:
Another possibility is that your case has either USB, Firewire, or Audio connections
available on the front of the case. It is very important that you look at your
motherboard manual for these connections. If it looks like your connectors from the
case and the connectors on the motherboard don't match up, then DON'T MESS
WITH IT! It is very easy to fry a motherboard since these types of connections
require a lot of power to travel through them. When in doubt, consult the manual or
call the case or motherboard company to get some help there. Better yet, check the
Message Boards to see if anyone else has had similar problems.
Remember
Once you make sure everything is hooked up, double check it!
Once you're sure everything is hooked up,
3.10 CHECK ALL CONNECTIONS
Yes, that's right, you're going to want to check your connections
AGAIN! There's no such thing as too safe when you're working with electronic
components that are sensitive to electricity.
This step will provide a checklist for you to go over, making sure that all your cables
are properly connected and secure:
Check List
1.
2.
3.
4.
5.
Make sure all the cards are seated well and screwed in
Check the power connections
Check the IDE and Floppy cables and master/slave settings
Check the front panel connectors
Check any other connections
Make sure all the cards are seated well and screwed in:
This includes the RAM. You want to make sure everything is secure in it's slot and
doesn't shift around when you lightly push it back and forth.
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Laboratory Module
Make sure all the power connections are secure and can't be easily pulled out. This
includes the power to the motherboard, CD/DVD drive, floppy drive, and any other
place that is using a power cable from the power supply.
Make sure the hard drive is on the cable that is connected to the primary plug on the
motherboard. Also check to make sure it is the master, and the other device on that
cable (if there is one) is the slave. Check the other IDE cable as well and make sure
all of them are securely plugged in.
Refer to your manual and double check all the connectors for the front panel. Make
sure that small triangle on the plastic plug leading from the case is on the positively
charged pin on the motherboard.
Double check any other connections you may have made and MAKE SURE that no
wires are near any moving parts such as the processor fan or the video card fan. If
possible, bundle the power cables together with a Velcro strap or even a zip tie.
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Laboratory Module
QUESTION:
o
o
o
o
o
Do you ever heard about DELL? Briefly explain who is DELL?
What is the heat sink used for?
What is the different between AMD and Microsoft?
What is the different between RAM and hard disk?
Discuss the importance of USB ports.
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Laboratory Module
INTRODUCTION TO OPERATING SYSTEM AND CONFIGURATION
4.0 SOFTWARE INSTALLATION
Most software installations are self explanatory or have something to guide you
through the process. In this step we will show you how to install Windows XP as
well as some of the basic things about installing drivers and other pieces of software.
Windows XP Installation
Windows XP is very easy to install but does require some input on your
behalf. Before you begin installation, remember, do not have ANY USB devices
connected to your computer, not even a MOUSE! This is a well known problem
with Windows XP. For some reason it doesn't like any USB devices connected while
installing Windows. If your mouse is a USB mouse, then find an adapter (PS/2
adapter) so that you can hook it up to the regular mouse port.
To Begin
Make sure the Windows CD is in the CD drive and turn on your computer. After the
computer boots up, the screen should ask this:
"If you wish to boot from the CD, press any key..."
Press a key and it will prepare to install windows. In order to install the operating
system you will need to format and partition the hard drive first. These two steps are
included in the installation so Windows will take you through them and make
recommendations about what kind of formats you should use. Without going into
detail, we will tell you that you should format the hard drive into one big partition
under the NTFS format. Do a full format, not quick. This will ensure a proper and
secure formatting of the hard drive.
Here's the screen that will show up when the formatting section begins.
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Laboratory Module
Image 1: Formatting session begin
Since this is a brand new install you will want to push Enter. Next it will ask you
which partition to format. There are sometimes two choices, but you'll want to
choose the one that has the largest MB size as seen below.
Image 2: Setting Windows
Once you go through and pick out your hard drive, make sure you do a full format in
the NTFS format. The next screen that shows up will look like the one below.
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Laboratory Module
Image 3: Format the partition
The size of your hard drive and speed of your processor will determine how long it
takes to completely format the hard drive. Once it's done, you're ready to install
Windows.
Windows will begin installing itself once the formatting ends. From there it will
basically run on autopilot, except when it needs to ask you for little bits of information
here and there. The first bit of information it will ask for is the Product Key to make
sure the copy of Windows you are installing is valid.
Image 4: Insert product key
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Laboratory Module
After that it will begin going through the install process.
Image 5: Install process
Another example of when it will ask for some information is when you need to input
the time and date. Why it does this somewhat in the middle of the process I'll never
know. If it weren't for this you would be able to start the install process and leave the
computer for an hour or two, but the way Windows installs requires you to check the
computer every once in a while. Here's the window that will pop up to ask for the
time and date.
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Laboratory Module
Image 6: Windows setup
Image 7: Date and time setting
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Laboratory Module
If you notice towards the bottom on the left side of the screen, it has an estimate of
how much longer the installation will take. Microsoft is surprisingly accurate now in
the XP version of windows so you can pretty much count on that being how long it
will take to finish.
Once it's done installing it will ask you to activate your copy of Windows. This is a
new step in Windows installation and has been established to prevent people from
pirating, or stealing, copies of Windows and installing them on as many computers
as they wish. It will ask you to activate windows, but it will also ask you to register
Windows. You have to activate but don't have to register...unless you want more
junk mail. Below is a picture of the activation screen.
Image 8: Activation choices
As you can see, there are three choices. Activate over the internet, activate over the
phone, or activate later. It really doesn't matter which one you choose, they all will
do the same thing in the end. If you are already connected to the internet then that
would be the fastest and easiest choice. If you aren't sure whether you have an
internet connection yet, choose to activate it over the phone. I've done both choices
and they're both fairly simple. If you want to activate later (within 30 days) then
choose the third option.
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Laboratory Module
Once you activate it you'll see this screen.
Image 9: Installation complete
Once Windows is installed you're almost ready to go. When Windows first starts up
it will go ahead and load the drivers for your hardware. This is another place where
the new version of Windows really shines. Most of your drivers will load
automatically, preventing you from having to manually go through and install each
individual one.
There may be a driver that has some difficulty loading and a window like the one
below will pop up.
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Laboratory Module
Image 10: Hardware installation
Don't worry, this is basically saying that Microsoft hasn't been able to test this
particular product and approve it. All this means is that whatever driver it's trying to
install is probably not as "mainstream" as many others. It would be impossible for
Microsoft to test absolutely every computer product out there with it's operating
system. This box is just saving their own butt in case something goes wrong. The
chances of something going wrong are very minimal. If something does go wrong,
all you have to do is consult the Message Boards to find a solution to your problem.
Once you have Windows installed, the first thing you'll want to do is update
it. Updating makes sure you're protected against the latest security issues and will
make sure your computer runs stable. Go to the Start menu, then All Programs,
then at the top there should be something called "Windows Update." Click on this
and follow the step by step process. The first thing that will be installed is called
SP1, or Service Pack 1. This will fix a number of security issues and is essential if
you want to make sure your computer is up to date. There may be other updates
but the only ones you need to seriously worry about are the ones considered
"critical." These will be in their own section of the Windows Update page. Just
follow the instructions online to install everything.
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Laboratory Module
Image 11: You're just about done!
4.1 FINISHING UP
The Final Step!
Protect Yourself From Hackers!
With the advent of broadband internet connections many people are switching from
dial-up to high speed internet connections. With this new form of "always on"
connections comes a risk of being invaded by hackers . One of the first things you
need to do is go to the Network Connections control panel in the Control Panel
folder. Once there you'll see a window like the one below.
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Laboratory Module
Image 12: Local area connection
Right click on the icon that says Local Area Connection and go to Properties as
shown above. Then another box will pop up. Once that happens click on the
Advanced tab as shown below.
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Laboratory Module
Image 13: Firewall
Make sure the box that says "Protect my computer and network...." is
checked. Once this is checked there is a wall of protection between your computer
and the outside world
47
UNIVERSITI MALAYSIA PERLIS
LAPORAN MAKMAL
Nama : ………………………………………Kumpulan : …………………….
Kursus : ………………………………………Tarikh : …………………
Computer hardware and assembly.
Instruction 1: Students are required to do an assembly for both type of casing.
Instruction 2: Be careful with computer hardware during computer assembly
Section 1: Assemble PC type tower.
1. Ensure there is no electrical connection.
2. Open your PC casing
3. Examine all the connection and remember the entire hardware placement.
4. Bring out all the listed hardware below. You must be careful in every step taken.
i.
ii.
iii.
iv.
v.
vi.
vii.
Power Supply
RAM
Hard Disk
CD drive
Floppy disk.
CPU
Motherboard
Seek the instructor approval while finish dissembles: ___________________
(Instructor)
You are required to assemble the computer.
5. Installing power supply.
i.
What is the rate for AC input for power supply? _______.
ii.
Discuss why there are two types of AC input.
______________________________________________
______________________________________________
______________________________________________
iii.
List down all the DC output depict in the power supply casing.
• ______
• ______
• ______
• ______
• ______
• ______
iv.
Discuss why there are different types of DC outputs for your PC?
_______________________________________________
_______________________________________________
_______________________________________________
6. Installing motherboard.
i.
Explain what the motherboard is.
_______________________________________________
_______________________________________________
_______________________________________________
Sketch your motherboard. State the entire hardware placement.
7. Installing processor.
This is the most crucial part and please be more cautious. Seek your instructor if you
don’t feel confident to do this.
i.
ii.
If available, write speed of your processor. ___________
What is the precaution step before installing processor?
iii.
iv.
Who is the manufacturer? _____________
In your own words, state the purpose of the microprocessor.
_________________________________________________
_________________________________________________
_________________________________________________
8. Installing RAM.
i.
RAM is the abbreviation from the words _____________________________
ii.
What is your RAM type? ____________
iii.
What is your RAM capacity? _________
iv.
If available, who is the manufacturer? ________________
9. Installing Hard disk
i.
What do you understand about hard disk?
ii.
If available, write all the information below;
• Manufacturer : ___________________
• Capacity : _______________________
iii.
What is the different between RAM and hard disk?
10. Installing video card
i.
Why must a PC have video card? Is it compulsory? Discuss.
11. Installing CD Drive.
i.
What does it mean by CD-RW?
ii.
What is DVD?
12. Installing Floppy disk drive
i.
List the steps taken during floppy drive installation.
13. Connect all the cables.
Check List
1.
2.
3.
4.
5.
Make sure all the cards are seated well and screwed in
Seek the instructor approval while finish dissembles: ___________________
(Instructor)
14. Refer to back side of your computer. Discuss with your partners and write the answer.
1. PS 2 ports for mouse
2. _________________
3. _________________
4. _________________
5. _________________
6. _________________
7. _________________
8. _________________
9. _________________
10. _________________
11. _________________
Section 2: Assemble PC type Desktop.
1. There are several differences between desktop and tower type. List all the differences and
compare.
i.
ii.
iii.
iv.
v.
vi.
Eg.
Power supply
RAM
Hard disk
CD drive
Floppy disk
CPU
i.
Power supply: there is no different between both power supplies. The input is
still 240V and it produces same output.
ii.
RAM:
iii.
Hard Disk:
iv.
CD Drive:
v.
Floppy disk :
vi.
CPU:
Lab Report
Name : ………………………………………Group : …………………….
Course: ……………………………………… Date : …………………
Installing operating system
ASSUME THE INSTALLATION IS FOR NEW COMPUTER
Follow the steps given.
.
1. Insert the Microsoft XP CD into your CD Driver.
2. Restart the computer and wait until the words below appear at the monitor screen.
"If you wish to boot from the CD, press any key..."
When the words appear, immediately hit any keyboard key.
3. After hit any key, these images appear.
4. Read the instruction. Hit key (i) ______ to set up Windows XP.
5. After hitting the key in (i), “Windows XP Licensing Agreement” depicted. To continue
installation process, hit key (ii) ______
6. Then you will be asked whether to repair of to install fresh copy of Windows XP. To
install fresh copy just hit key (iii) ________.
7. The computer used, previously installed with Windows XP. So, the partition at drive C
must be deleted first. Hit key (iv) ________ to delete the partition.
8. Immediately after pressing key (iv), new screen appear. Read and understand the
statement. To continue press key (v) ______. But, if you want to return, press key (vi)
_____.
9. New instruction comes out. Read and understand it. Choose key (vii) _____ to delete the
partition at drive C.
10. Next, the same instruction as is step 6 appears. To install fresh Windows XP key (viii)
____ must be press.
11. If you hit the right key in step 9, a new instruction appears. Read and understand it. Use
the up ( ) and down ( ) key and select
Format the partition using the NTFS file System
Press key (ix) ___ ____ to proceed.
12. If the step 1- 10 are correctly followed. The image as shown below appears.
13. The above process is known as format. What do you understand with this process?
Discuss with your friends and write below.
14. The above process requires 30 minutes to complete. Do you agree hard disk capacity and
speed of CPU plays and important factor in this process? Discuss with your friend.
15. After the formatting process complete, the computer will reboots itself. Just wait and see.
16. Then another instruction appears “Regional and language options”. Read and
understand it, if there any changes, fix it. After that hit the next key
17. If the instruction “Personalize your computer”. Enter name and organization. Write
what is the name and organization typed. Write below.
Name:
Organization:
18. As requested, key in the given CD key.
CD KEY: 47YK2 – D8R6C – BPQBY – F4R3R - TVBTH
19. If there is no mistake in typing the CD key, new instruction appears. Press NEXT.
20. When you reach the instruction as below, just change the time, date and time zone
21. After that, just keep pressing NEXT until your computer reboot again.
22. What is “reboot”? Explain.
23. Wait for another instruction. Read, understand it and proceed until you reach at the
instruction as shown below.
There is no internet connection in this lab.
Discuss with your friend what is internet.
24. If the instruction as below appear. This means you have successfully installed Windows
XP.
25. In drive D, click software folder. Install software as listed below.
i). Norton antivirus
ii). Microsoft Office 2003 (CD key: GWH28-DGCMP-P6RC4-6J4MT-3HFDY)
iii). Adobe acrobat reader
JAWAPAN.
(i).
(ii).
(iii).
(iv).
(vi).
(vii).
(viii).
(ix).
(v).
Electronic
Circuits
OrCad Software Manual
DCT100
LAB 1: USING OrCAD Capture
OBJECTIVE:
At the end of this session you should be able to:(i)
(ii)
draw a schematic using OrCAD Capture CIS.
do the finishing to the schematic to create a printed circuit board (PCB)
DRAWING SCHEMATICS
1. To begin, choose Capture CIS program from your desktop, select options
File>New>Project as shown in the figure below.
Figure 1.1: The initial window of OrCAD Capture
2. This option will invoke the New Project dialog box, as shown in Figure 1.2 below.
You should name your project as PCB1_yourname, and create new project using
PC Board Wizard and create your own directory as shown in Figure 1.3.
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DCT100
Figure 1.2: New Project dialog window
Figure 1.3: Select directory window
3. Then, dialog box as shown in figure below displays, just click Next to continue.
Figure 1.4: PCB Project Wizard
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DCT100
4. The next step is to load libraries of parts which will be available to you when you
are drawing the circuit schematics. The dialog box is for adding and removing
libraries is shown Figure 1.5 below. You might add or remove the libraries later,
now click Finish and continue to draw the schematic.
Figure 1.5: Add or Remove libraries dialog box
5. Draw the circuit as shown in the Figure 1.6 below.
Figure 1.6: Sample for Schematic
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DCT100
6. Place component by select option Place>Part… as shown in the figure 1.7 below
Figure 1.7: Place part option
7. When Place Part windows appear as figure 1.8 below, select all libraries name and type
a component name in blank space depending on what type of component we want to use.
Refer to Appendix A given, enter the appropriate component name for each one of the
parts in the schematic.After that click on the component name and click OK. Place part
into Orcad capture window. Repeat step no. 7 until all components placed.
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DCT100
Figure 1.8: Place Part window
8. When finish draw the schematic, select all component from the Edit menu or by
pressing Ctrl+A. Then, from Edit menu, click Properties or Ctrl+E to edit the
properties of all the parts. The window as in figure below appears. Choose filter by
Layout. Select Parts tab.
Unversiti Malaysia Perlis
5
DCT100
Figure 1.9: Property Editor window
9. Refer to Appendix A given, enter the appropriate footprint for each one of the parts in
the schematic as shown in figure below. Click the PCB footprint cell for any one of
the parts, type the footprint name. Notice that you must recognize physically how the
parts look like in order to specify their correct footprint.
Figure 1.10 : Specify a PCB footprint
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DCT100
FINISHING SCHEMATICS
1. Now, displays the Capture’s project manager window, click schematic page as
shown in the figure below.
Figure 1.11 : Project Manager window
2. Annotate the design by choosing Tools>Annotate or by clicking
button from
the toolbar. This is for update the part reference to prepare the netlisting.
Annotate menu window will appear as shown below. Click OK to annotate.
Another dialog appears as shown in figure 1.11. Click OK to continue.
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DCT100
Figure 1.12: Annotating design
Figure 1.13
3. The design must be check for multiple parts of same reference or invalid package
or nets. Design Rules Check (DRC) will do this. Choose Tools>Design Rules
Check or click
button from the toolbar. DRC menu as shown below appear. If
there are errors, dialog box such in figure 1.13 will appear.
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DCT100
Figure1.14: Design Rules Check ( DRC )
Figure 1.15: Error in DRC
4. If DRC does not give any error, proceed by creating netlist for PCB Layout. If
otherwise, you must identify and fix the problems.
5. To create netlist for PCB, choose Tools>Create Netlist or click
button from
the toolbar. Netlist menu as shown below display. Select the desired netlist type
by clicking the Layout tab. Click OK to create netlist. Save your design by
clicking OK for the next dialog box. See figure 1.16.
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DCT100
Figure 1.16: Create Netlist for the design
6. Close and save your design.
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DCT100
LAB 2: USING OrCAD Layout
OBJECTIVE:
At the end of this session you should be able to:(i)
create a printed circuit board.
(ii)
do placement of the component, manually or automatically routing the board
INTRODUCTION
OrCAD Layout
OrCAD Layout is a powerful circuit board layout tool that has all the
automated functions you need to quickly complete you board. The chart in the
figure below illustrated Layout’s design flow.
Figure 2.0: PCB Design Flow
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DCT100
From figure above, by using OrCAD Capture, we can create a Layoutcompatible netlist. This netlist contains much of the design information that
Layout uses to produce the board. Next step is placing components by using
OrCAD Layout, we can
either manually route or autoroute the board. As an output, OrCAD Layout will
produces hardcopy on printers and plotters, and also Gerber files for
Gerber photoplotter, and a wide variety of report files. We can preview or even edit
a Gerber files with Layout’s external Gerber editor known as GerbTool.
PCB Consideration
All PCB are divided into layers. OrCAD Layout supports up to 30 routing layers,
it displays the PCB from a top view. Layers can be a copper layers or
documentation layers. Base on this consideration, we need to clarify this particular
information such
as numbers of layers, size and shape of the PCB, PCB fabrication plant specifications
that include minimum trace and space width, plating reduction and available drills.
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DCT100
CREATING A PRINTED CIRCUIT BOARD
1. Run OrCAD Layout program, select options File>New as shown in figure below.
Figure 2.1 : Initial window of OrCAD Layout
2. Layout window will appear with Load Template File dialog box as shown in
Figure 2.2 below, choose DEFAULT template to use in this design. Template can
be found in folder C:>Software>OrCAD>Layout>DATA and just click Open
button to next step.
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DCT100
Figure 2.2: Loading template file
3. Next, Load Netlist Source dialog box appear. You need to load your netlist file
that you have created in the previous session, which is PCB1_YOURNAME.MNL
as shown in figure below.
Figure 2.3 : Load a netlist file
4. You will be asking to save your board file, save
PCB1_YOURNAME in your own folder as described below.
your board as
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DCT100
Figure 2.4: Saving file
5. If there were no error during AutoECO process, your design will appear to be as
in figure 2.5 below. However if there are error, Layout might abort the process
and you will need to identify and fix the problem accordingly.
Figure 2.5: View of layout design window
15
6.
DCT100
OrCAD design window settings are controlled by system settings and
user settings. To change system settings, select options Option>System
Settings. Dialog box as in figure 2.6 below display.
Figure 2.6: System Setting dialog window
7. Now, you can start to place the component manually by clicking
button.
Sample of complete placement of the component is shown the figure 2.7 below.
8. Choose Obstacles tool using
button, right click in the window and choose
New. Draw the obstacle as shown in figure 2.7 below.
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DCT100
Figure 2.7: Sample of placed component and Draw Obstacle
9. Left click and then right click on the obstacles, choose Properties. Edit
Obstacles dialog box display as shown in figure 2.8 below. Select Obstacles
Type to Board Outline. Click OK button to finish obstacle command.
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DCT100
Figure 2.8: Edit Obstacle dialog window
10. Now, click on the
button to view the spreadsheet and select Layers. A dialog
box such in figure 2.9 appear.
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DCT100
Figure 2.9: Layers dialog box
10. Click on the layer type column of layer name TOP, right click and
choose properties. Select Layer Type to Unused Routing as shown in figure
below. Do the same modification to INNER1 and INNER2 layers. As routing
will be on the bottom layer only, the PCB is a single layer board (single-sided
PCB). Click OK and close Layers dialog box. Please see figure 2.10 for edit
layer.
11. For double layer ( double sided PCB) , change Layer Type of layer TOP and
BOTTOM to Routing but Unused Routing for layer INNER 1 and INNER 2.
Please see figure 2.10 for edit layer
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DCT100
Figure 2.10: Edit Layer dialog box
12. In order to begin routing, you need to set net properties, choose the
spreadsheet toolbar again and select Nets. The Nets spreadsheet displays as
shown in figure 2.11 below.
Figure 2.11 : Nets spreadsheet
13. Double click on net you want to edit, the Edit Net dialog box displays as
shown in figure 2.12 below. Modify the settings that you want and click OK.
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DCT100
Figure 2.12: Edit Net dialog box
15. To route the board automatically, choose Auto>Autoroute>Board. The board will
be route automatically as shown in the sample below. The default color for
BOTTOM layer route is red and TOP layer route is blue.
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DCT100
Figure 2.13: Sample of routing board
16. Next, after the routing is done, choose Auto>Cleanup to smoothes the route on the
board.
17. If there any modification that need to be done to route, you can click on the
or
button and click on the particular net and do manual routing.
18. When finish, select Auto>Design Rule Check. Dialog box as in figure below
appear. Click OK to run DRC.
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Figure 2.14 : Check Design Rules (DRC)
19. If there are no errors, proceed with creating Gerber files for the board. Select
Options>Gerber Settings… to view the settings, for post process settings select
Options>Post Process Setting…
20. To produce Gerber files for the board, select Auto>Run Post Processors. Click OK
to the both of the dialog box that appear as shown in figure 2.15 and figure 2.16 below
Figure 2.15
Figure 2.16
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21. To view a Gerber file for the design, from OrCAD Layout window, select
Tools>GerbTool>Open. See Figure 2.17 below. Choose file
PCB2_YOURNAME and click OK. Show the PCB2_YOURNAME – GerbTool
window to the instructor for verification.
Figure 2.17
22. Save and close your work.
23. Now you can use your gerber data and tooling data to produce PCB.
APPENDIX A
Components
NE555
RESISTOR
CAP
CAP POL
LED
SW_PB_SPST
Quantity
1
3
1
1
1
1
Footprints
DIP.100/8/W.300/L.450
AX/.400X.100/.034
RAD/CK05
CPCYL1/D.200/LS.150/.031
CYL/D.225/LS.100/.031
RAD/.300X.250/LS.200/.031
24
CPCYL1/D.200/LS.150/.031
CYL/D.225/LS.100/.031
RAD/.300X.250/LS.200/.031
DCT100
DIP.100/8/W.300/L.450
AX/.400X.100/.034
RAD/CK05
25
Laboratory Manual for DCT100
(UniMAP)
LABORATORY MANUAL
DCT 100 - ELECTRONIC CIRCUIT
©2010 Universiti Malaysia Perlis
LAB 2
PROTOTYPING TECHNIQUE, TEST & MEASUREMENT OF
ELECTRONIC CIRCUIT
OBJECTIVES:
At the end of this lab session you should be able to
i.
identify basic electronic components and its properties.
ii.
know basic prototyping technique by using Vero board.
iii.
perform soldering skills with good results.
iv.
use basic lab instruments; power supply unit, oscilloscope, and function
generator
INTRODUCTION
In this section, a simple introductory to a few electronic components will be
carried out based on one timer circuit. A brief explanatory about lab instruments
will be discussed then.
Figure 1: Timer Circuit
Component Listing
Resistor – 10kΩ, 47kΩ and 470Ω
Capacitor - 100µF and 0.01µF
555 Timer
LED
Resistor – Reading the Resistor Colour Codes
Black Brown Red Orange Yellow Green Blue Violet Gray White
0
1
2
3
4
5
6
7
8
9
Black is also easy to remember as zero because of the nothingness common to
both.
Figure 2: Resistor and its
symbol
How to read the code
a) First find the tolerance band, it will typically be gold ( 5%) and
sometimes silver (10%).
b) Starting from the other end, identify the first band - write down
the number associated with that color; in this case Blue is 6.
c) Now 'read' the next color, here it is red so write down a '2' next to
the six. (you should have '62' so far.)
d) Now read the third or 'multiplier' band and write down that
number of zeros. In this example it is two so we get '6200' or
'6,200'. If the 'multiplier' band is Black (for zero) don't write any
zeros down. If the 'multiplier' band is Gold move the decimal
point one to the left. If the 'multiplier' band is Silver move the
decimal point two places to the left. If the resistor has one more
band past the tolerance band it is a quality band.
Capacitor
+
(a)
(b)
Figure 3: Polarized (a) and non-polarized (b) capacitor
and its symbols
1. Large capacitor have the value printed plainly on them, such as 10.µF (Ten
Micro Farads) but smaller disk types along with plastic film types often
have just 2 or 3 numbers on them.
2. First, most will have three numbers, but sometimes there are just two
numbers. These are read as Pico-Farads. An example: 47 printed on a
small disk can be assumed to be 47 Pico-Farads.
3. For the 3 numbers, it is somewhat similar to the resistor code. The first two
are the 1st and 2nd significant digits and the third is a multiplier code. In the
table below show the value of the third significant digit. The result from the
multiplication is in Pico-Farad.
Third digit
0
1
2
3
4
5
6
7
8
9
Multiplier (the first two digits
gives you the value in PicoFarads)
1
10
100
1,000
10,000
100,000
not used
not used
.01
.1
Table 1: Multiplier Table for Capacitor
Example: A capacitor marked 104 is 10 with 4 more zeros or
100,000 pF which is otherwise referred to as a .1 µF
capacitor.
Timer (555)
Figure 4: Timer IC
1. The 555 is a highly stable device for generating accurate time delays or
oscillation.
2. The pin description of this IC is given in figure 5 below.
Figure 5: 555 Timer Pin Descriptions
3. The basic operation for 555 timer is as shown in figure 1, where the
parameter C1 and R1 determine the time period for output pin (6) to
become ‘hi’ where the LED will be on for 5 seconds with 100 µF for C1
and 47 kΩ for R1.
4. User may try to change the value for C1 and R1 where R1 should be in
the range of 1 kΩ to 1 MΩ, and the time period is defined by
T = 1.1 x R1 x C1
LED
1. LED (light emitting diode) is diode that allows an electric current to flow in
one direction, but essentially blocks it in the opposite direction (or can be
think as an electronic valve) PLUS, LED emit light that normal diode can
not.
Anode
Cathode
Figure 6: LED Symbol
LAB INSTRUMENTS
Digital Multimeter
1. Digital multimeter is one of the most versatile instruments, usually
containing three different meters in one.
a. The voltmeter measures the electrical potential difference across a
device (in volts)
b. An ammeter measures the amount of electrical current flowing
through a device (in amperes or amps)
c. An ohmmeter measures the electrical resistance of a device (in
ohms).
2. Digital multimeter gives an output in numbers, usually on a liquid crystal
display (LCD). A switched ranges multimeter is shown below.
Figure 7: Switched Range Multimeter
3. The central knob has lots of positions and you must choose which one is
appropriate for the measurement you want to make. If the meter is switched
to 20 V DC, for example, then 20 V is the maximum voltage which can be
measured, this is sometimes called 20 V fsd, where fsd is short for full scale
deflection.
4. There are 2 types; AC and DC that can be measure using multimeter. DC
always indicated by
, whereas AC as
.
Measuring Current
a) In figure 8 below show a circuit before and after connecting a
multimeter (in this case, multimeter work as an ammeter, measuring
current).
Figure 8: Measuring Current
b) To measure current, the circuit must be broken to allow the ammeter to
be connected in series. Thus, the ammeter must have a LOW internal
resistance.
Measuring Voltage
a) In figure 9 below, show a circuit before and after connecting a
multimeter (in this case, multimeter work as an voltmeter, measuring
voltage).
Figure 9: Measuring Voltage
b) To measure potential difference (voltage), the circuit is not changed;
the voltmeter is connected in parallel and thus, the voltmeter must
have a HIGH resistance.
Measuring Resistance
a) An ohmmeter does not function with a circuit connected to a power
supply. To measure the resistance of a particular component, you must
take it out of the circuit altogether and test it separately, as shown in
figure 9 below.
Figure 10: Measuring Resistance
Digital Oscilloscope
1. Oscilloscope is a powerful lab instrument used for measuring electronic
signal such as DC or even AC signal for broad range of applications.
2. In this lab session, we will use digital oscilloscope from Tektronix, model
TDS 1002 with 2 channel input. In figure 11 below show the front panel of
this type of oscilloscope.
Figure 11: Tektronix TDS 1002
3. To measure signal, probe must be used (figure 12) and have to be
connected to any channel (1 or 2) at the oscilloscope. For current lab
session, please verify that the probe attenuation is set to 1X.
Figure 12: Probe
Taking Simple Measurements
1. Connect probe to channel 1 port (labelled CH1) at the oscilloscope.
2. Connect the other end of the probe to PROBE COMP, and press
AUTOSET button.
3. The oscilloscope will automatically set the vertical and horizontal
settings.
4. The signal displayed on the oscilloscope now is pulse signal with
voltage amplitude 5 V and 1 kHz frequency.
5. You may try to adjust the vertical and horizontal controls by using
SEC/DIV and VOLTS/DIV knob to fit your needs.
Power Supply Unit
1. For power supply usage for any experiment in this lab, we will use
TOPWARD – Dual Tracking DC Power Supply model 6303D.
2. In figure 13 below show the front panel for this instrument.
Figure 13: TOPWARD – Dual Tracking DC Power Supply Unit (6303D)
3. This device have the following features:
a) Twin power output with tracking function for automatic selection of
parallel or serial connection
b) Short-circuit protection against external input while providing
constant voltage and constant current
c) Allows serial or parallel connection with the same power supply
model
d) 5V/5A constant-voltage output
4. For this lab session, we only interested in independent mode where only 1
output will be used, and also 5V/5A constant voltage output.
5. To use the power supply in independent mode, the following steps must
be taken:a) Set the TRACKING MODE switches on the front panel to IND.
b) Turn on the POWER switch.
c) Open the circuit between the + and the - output terminals. Turn the
voltage adjustment knob clockwise until you get the desired output
voltage rating.
d) Turn the current adjustment knob counterclockwise until you get the
minimum value.
e) Short the circuit between the + and the - output terminals.
Note
that the current rating of the shorting wire should be greater than or
equal to the required current.
f) Turn the current adjustment knob clockwise until the current
indicator on the front panel displays the required current rating.
g) Remove the shorting wire from the + and the - output terminals.
The power supply returns to the constant voltage mode and is
ready to use.
6. To use as fixed 5V/5A output, simply connect the positive (+ve) and
negative (-ve) probe to any device that need to power up. If short circuit
occur or the load exceeds 5 amperes, the red OVERLOAD LED lights up
and prevent damage to the device.
Function Generator
Figure 14: INSTEK Function Generator (GFG-8020H)
1. Function generator provides square, triangle, sine and pulse waveform
over a frequency range from 0.2 Hz to 2 MHz.
2. To use the function generator for example to generate sinusoidal
waveform with frequency 1 MHz, the steps are:
i. Power up the function generator
ii. Connect the cable to the port output at front panel of the
function generator
iii. Press the sine waveform function switch
iv. Adjust the Multiplier so that 1 MHz sine wave is produced
v. You may try to connect the other end of the cable to
oscilloscope to see the waveform produced
INTRODUCTION TO SOLDERING PROCESS
Introduction
1. Vero board has parallel strips of copper track on one side. The tracks are 0.1"
(2.54mm) apart and there are holes every 0.1" (2.54mm).
2. Vero board is used to make up permanent, soldered circuits. For large,
complex circuits it is usually best to use a printed circuit board (PCB).
3. Avoid handling Vero board that you are not planning to use immediately
because sweat from your hands will corrode the copper tracks and this will
make soldering difficult. If the copper looks dull, or you can clearly see finger
marks, clean the tracks with fine emery paper, a PCB rubber or a dry kitchen
scrub before you start soldering.
Placing components on Vero board
1. Components are placed on the non-copper side, and then the Vero board is
turned over to solder the component leads to the copper tracks. This means
that the tracks are out of sight under the board.
2. For most small circuits the best method is to very carefully place the chip
holder(s) in the correct position and solder in place. Then you can position all
the other components relative to the chip holder(s).
Figure 15: Soldering side
Cutting Vero board tracks
1. Most Vero board circuits will need to have some tracks cut to break the
connection at that point. This is always necessary under ICs, except for the
rare cases where opposite pins must be connected. The tracks are cut with a
special track cutter tool or a 3mm drill bit.
2. Place the track cutter on the correct hole with moderate force. The aim is to
break the copper track, not drill a hole through the board! Inspect the cut
closely to ensure there is no fine thread of copper left across the break,
because even the tiniest piece will conduct.
Soldering Guide
A few safety precautions:
•
Never touch the element or tip of the soldering iron.
They are very hot (about 400°C) and will give you a nasty burn.
•
Always return the soldering iron to its stand when not in use.
Never put it down on your workbench, even for a moment!
•
Work in a well-ventilated area.
The smoke formed as you melt solder is mostly from the flux and quite
irritating. Avoid breathing it by keeping you head to the side of, not above,
your work.
•
Wash your hands after using solder.
Solder contains lead which is a poisonous metal
Preparing the soldering iron:
Figure 16: Soldering iron
•
Place the soldering iron in its stand and plug in.
The iron will take a few minutes to reach its operating temperature of
about 400°C.
•
Dampen the sponge in the stand.
The best way to do this is to lift it out the stand and hold it under a cold tap
for a moment, then squeeze to remove excess water. It should be damp,
not dripping wet.
•
Wait a few minutes for the soldering iron to warm up.
You can check if it is ready by trying to melt a little solder on the tip.
•
Wipe the tip of the iron on the damp sponge.
This will clean the tip.
•
Melt a little solder on the tip of the iron.
This is called 'tinning' and it will help the heat to flow from the iron's tip to
the joint. It only needs to be done when you plug in the iron, and
occasionally while soldering if you need to wipe the tip clean on the
sponge.
What is solder?
Solder is an alloy (mixture) of tin and lead, typically 60% tin and 40% lead. It melts at
a temperature of about 200°C. Coating a surface with solder is called 'tinning'
because of the tin content of solder. Lead is poisonous and you should always wash
your hands after using solder.
Figure 17: Solder
Solder for electronics use contains tiny cores of flux, like the wires inside a mains
flex. The flux is corrosive, like an acid, and it cleans the metal surfaces as the solder
melts. This is why you must melt the solder actually on the joint, not on the iron tip.
Without flux most joints would fail because metals quickly oxidize and the solder
itself will not flow properly onto a dirty, oxidized, metal surface.
You are now ready to start soldering:
1. Place the soldering iron tip against both the lead and the circuit board foil.
Heat both for 2 or 3 seconds
Figure 18: Positioned the soldering iron
2. Then apply solder to the other side of the connection.
3. Important: Let the heated lead and the circuit board foil melt the solder.
Figure 19: Use solder
4. As the solder begins to melt, allow it to flow around the connection. Then
remove the solder and the iron and let the connection cool.
Figure 20: Solder melt
Inspect the joint closely.
It should look shiny and have a 'volcano' shape. If not, you will need to reheat it
and feed in a little more solder. This time ensure that both the lead and track are
heated fully before applying solder.
Figure 21:
Comparison bad
and good joins
Desoldering
At some stage you will probably need to desolder a joint to remove or re-position
a wire or component. You can remove the solder with a desoldering pump or
always known as solder sucker.
•
Set the pump by pushing the spring-loaded plunger down until it locks.
•
Apply both the pump nozzle and the tip of your soldering iron to the joint.
•
Wait a second or two for the solder to melt.
•
Then press the button on the pump to release the plunger and suck the
molten solder into the tool.
•
Repeat if necessary to remove as much solder as possible.
•
The pump will need emptying occasionally by unscrewing the nozzle.
LAB ACTIVITIES 1
R3
R2
D1
Component
Item
Vero board
Resistors
10 kΩ
47 kΩ
470 Ω
Capacitors
100 µF
0.01 µF
Socket IC (8 pins)
555 Timer IC (8 pins)
LED
2 way header
Switch
Quantity
1
1
1
1
1
1
1
1
1
1
1
1. By using Vero board planning sheet below, show the component
placement and connection. Show only the parallel strips that will be used
in your soldering activities.
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2.
By using the Vero board planning sheet from the previous question,
make a connection at the Vero board.
3.
What is the precaution should be taken?
4.
Explain how the circuit works, and suggest the use of this circuit in daily
applications.
5.
What is the time required for LED to turn on? Show the calculation
step.(Tips: Time Period, T = 1.1 × R1 × C1)
6.
If the circuit can’t function well, can you assume, which part will
contribute to the problem? List all. (e.g. No battery or misconnection)
7.
Measure the voltage across R1.
8.
9.
10. Measure the voltage across C1.
11. What is the value of current flow through R1?
12. What is the value of current flow through R2?
13. Predict, what is the current through D1? Explain why?
LAB ACTIVITIES 2
1. Modify circuit from lab activities 1 above to the circuit given below.
+9V
R3
Inspect the output using oscilloscope. Draw the output by scale on your answer
sheet. Give frequency, f, period, t, and amplitude, A of the resulting output.
Electrical
Wiring
LABORATORY
MODULE
DCT100
Electrical Wiring
Semester 1 (2011/2012)
Sharulnizam bin Mohd Mukhtar
Wan Mohd Faizal bin Wan Nik
Mohd Wafiuddin bin Yahya
ENGINEERING CENTRE
Basic Engineering skills (DCT100)
Content
Preface
Introduction
LAB 1: PVC CONDUIT WIRING SYSTEM
Wiring of 2 x 2 way switch and 1 x Intermediate switch controlling a lamp and
the installation of 13A socket outlet
LAB 2: SCREWED STEEL CONDUIT WIRING SYSTEM
Wiring of 2 x 1 way switch controlling incandescent and fluorescent lamp and
the installation of 13A socket outlet.
@2011 Universiti Malaysia Perlis (Unimap)
LAB 1: PVC CONDUIT WIRING SYSTEM
Wiring of 2 x 2way switch and 1 x Intermediate switch
controlling a lamp and the installation of 13A socket outlet
OBJECTIVE:
After performing this experiment, you will able to:
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Understand the operation and the wiring of 2 x 2 way switch circuit and 1 x
Intermediate switch circuit.
Make the installation of the PVC conduit wiring system
Understood the IEE regulation governing with this installation.
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MATERIAL
20mm PCV Conduit
4 x Surface PVC Boxes
2 x 13 Amp Socket outlet
2 x 1 Gang 2 Way Plate switch 6 Amp
4 x 20mm PVC Tee Box
2 x 20 mm PVC Inspection Bend
1 x 20mm PVC Terminal Box
1 x Batten Holder
1 x 20mm PVC Male Bush
1 x 20 mm PVC coupler
PVC conduit saddle
1.25mm white Cable
1.25mm green cable
2.5mm white cable
2.5mm green cable
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TOOLS
Screw driver
Wire cutter
Wiring hammer
Test pen
Measuring tape
Multimeter
Gimlet
Conduit cutter
Conduit Bending Spring
Plier
Long Nose
Cable Striper
Figure 1.1: Theoretical circuit of 3 switches controlling a lamp
Bending
1. To bend circular conduit, insert the appropriate spring. The spring has an “eye”
formed on one end, to which a cord should be attached in order to withdraw the
spring.
Figure 1.2: Figure shows the spring inserted into the PVC conduit
2. The bend is then made by hand or across the knee, twice the angle required
should be bent and the tube then allowed to ease back to the desired position.
Do not attempt to force the bend back with the spring inserted, as this action will
damage the spring.
Figure 1.3: Figure shows how to bend the PVC conduit
3. When withdrawing the spring it is suggested that it be twisted in an anti-clockwise
direction thus reducing the diameter of the spring and providing easy withdrawal.
4. It is important to use the correct size spring. In cold weather it may be necessary
to warm the tube slightly at the point where the bend is to be made. Always
saddle the tubing as quickly as possible after bending.
Figure 1.4: The conduit bending spring
PROCEDURE:
1. According Figure 1.5 , draw the wiring circuit containing 2 x 2 way switch and 1 x
Intermediate switch controlling 1 x lamp and 1 x 2 Gang 13A socket outlet.
2. Measure the length of required PVC conduit using the conduit cutter.
3. Install saddle to the wiring board with the proper size and distance
4. Do the wiring according to the wiring circuit from distribution board and marking
the cable to differentiate the live and neutral cable.
Figure 1.5: Figure show circuit containing 2 x 2 way switches and 1 x
intermediate switch controlling a lamp and 1 x 2 Gang 13A socket outlet
5. Install the conduit to conduit accessories according to the drawing.
6. Do the bend using the conduit bending spring as described above.
7. Install all the wiring accessories to the wiring board.
8. Test your circuit for continuity and short circuit.
9. Test your circuit with 240V supply after get permission from lab engineer.
RESULT:
OPERATION
S1
S2
S3
1
OFF
OFF
OFF
2
ON
OFF
OFF
3
ON
ON
OFF
4
ON
ON
ON
5
ON
OFF
ON
6
OFF
OFF
ON
7
OFF
ON
ON
8
OFF
ON
OFF
L1
Instructor Approval: ___________________________ Date: _________________
Name:_____________________________________ Date:____________________
Matric No:_____________
DRAWING:
Name:_____________________________________ Date:____________________
Matric No:_____________
DISCUSSIONS:
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Name:_____________________________________ Date:____________________
Matric No:_____________
CONCLUSION:
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LAB 2: SCREWED STEEL CONDUIT WIRING SYSTEM
Wiring of 2 x 1 way switch controlling 2 lamps separately and
1 x 2 gang 13A socket outlet
OBJECTIVE:
After performing this experiment, you will able to:
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Understand the operation and the wiring of 1 way switch circuit and wiring of
fluorescent lamp.
Make the installation for the given screwed steel conduit wiring system
Understood the IEE regulation governing with this installation.
MATERIAL
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20mm Galv Conduit
1 x 13 Amp 2 Gang Switched Metal clad
Socket
2 x 1 Gang 2 Way Metal clad Switch
1 x 1 Gang Intermediate switch
1 x 20mm Galv 4 Way Box
2 x 20 mm Galv Inspection Bend
2 x 20mm Galv Inspection Tee
1 x 20mm Galv Terminal Box
1 x Batten Holder
1 x 60W Pearl Lamp
5 x 20mm Female Adaptors with Bush
4 x 20mm Galv coupler
Galv conduit saddle
1.25mm white Cable
1.25mm green cable
2.5mm white cable
2.5mm green cable
TOOLS
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Screw driver
Wire cutter
Wiring hammer
Test pen
Measuring tape
Multimeter
Gimlet
Hacksaw
Conduit Bending Machine
Plier
Long Nose
Cable Striper
Figure 2.1: Theoretical circuit of 1 switch controlling a lamp
PROCEDURE:
1. According to the above block diagram, draw the wiring circuit.
2. Draw the basic wiring diagram on the wiring board according to the given size.
3. Measure the length of required Galvanized pipe and cut using the hacksaw and
after cutting burns should be removed using a file or reamer.
4. Do the threading using a threading machine.
Figure 2.2: Figure show circuit containing 2 x 1 way switch controlling 2 lamps
separately and 1 x 2 Gang 13A socket outlet
5. Install saddle to the wiring board with the proper size and distance
6. Install the conduit to conduit accessories according to the drawing.
7. Do the bend using the conduit bending machine.
8. Do the wiring according to the wiring circuit from distribution board and marking
the cable to differentiate the live and neutral cable.
9. Install 1 Gang 1 Way Metal clad Switch together with 13 Amp 1 Gang Switched
Metal clad Socket.
Figure 4.3: Figure shows the wiring of fluorescent lamp.
10. Test your circuit for continuity and short circuit.
11. Test your circuit with 240V supply after get permission from lab engineer.
Figure 4.4: Figure of conduit bending machine
Name:_____________________________________ Date:____________________
Matric No:_____________
RESULT:
Operation
S1
S2
1
OFF
OFF
2
OFF
ON
3
ON
OFF
4
ON
ON
L1
L2
Name:_____________________________________ Date:____________________
Matric No:_____________
DRAWING:
Name:_____________________________________ Date:____________________
Matric No:_____________
DISCUSSIONS:
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
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_____________________________________________________________________
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Name:_____________________________________ Date:____________________
Matric No:_____________
CONCLUSION:
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Mechanical
Workshops
Lab 1: Metrology
Laboratory Manual for Basic Engineering Skills DCT 100
LAB 1
METROLOGY
1.0
OBJECTIVE
Learn to handle basic mechanical measuring techniques, to practice measuring sample
parts, to impress students that the degree of accuracy and precision depends upon the
skill.
2.0
1.
2.
3.
4.
5.
6.
3.0
EQUIPMENTS / APPARATUS
Micrometer
Vernier Caliper
Inside Micrometer
Depth Micrometer
Height Micrometer
Dial Indicator
INSTRUCTIONS ON USE
3.1 Micrometer
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The micrometer is an extremely precise measuring instrument; the reading error is
1/200 mm = 0.005 mm.
Use the rachet knob (at the far right in the picture above) to close the jaws lightly on
the object to be measured. It is not a C-clamp! When the rachet clicks, the jaws are
closed sufficiently.
The tick marks along the fixed barrel of the micrometer represent halves of
millimeters.
Every revolution of the knob will expose another tick mark on the barrel, and the jaws
will open another half millimeter.
Notice that there are 50 tick marks wrapped around the moving barrel of the
micrometer. Each of these tick marks represents 1/100 millimeter.
To read the distance between the jaws of the micrometer, simply add the number of
half-millimeters to the number of hundredths of millimeters.
If two adjacent tick marks on the moving barrel look equally aligned with the reading
line on the fixed barrel, then the reading is half way between the two marks.
©2008 Universiti Malaysia Perlis (UniMAP)
Page 1 of 8
Lab 1: Metrology
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The micrometer may not be calibrated to read exactly zero when the jaws are
completely closed. Compensate for this by closing the jaws with the rachet knob until
it clicks. Then read the micrometer and subtract this offset from all measurements
taken. (The offset can be positive or negative.)
On those rare occasions when the reading just happens to be a "nice" number like 2
mm, don't forget to include the zero decimal places showing the precision of the
measurement and the reading error. So not 2 mm, but rather (2.000 ± 0.005) mm.
3.2 Vernier Caliper
1. Outside caliper jaws are used to close
around the outside of an object. these are
the jaws mostly used.
2. Inside caliper jaw fit into hole and measure
the inside dimension.
3. The depth probe measure the depth of
hole.
4. With both locking screws loose the lower
jaw is free to move. Initially close the jaws
loosely around an object and then tighten
the coarse locking screw.
5. The fine adjust thumbscrew allows the
jaws to be close to a snug fit.
6. The Final Locking Screw locks the lower
jaw so that the caliper can be removed
from the object to be read.
7. Reading the caliper is done in two steps,
reading the Main Scale and reading the
Vernier.
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Check that the caliper correctly reads zero
when the jaws are closed.
Close the jaws around the object but do not
over tighten. The jaws should exert a firm
pressure on the object.
When both locking screws are tightened
the caliper can be removed from the object
and read without worrying if the jaws will
shift position
Page 2 of 8
Lab 1: Metrology
o You can read the main scale to the nearest tenth of a centimeter.
o The vernier consists of 50 divisions, meaning that 0.1 cm is divided into
50 parts and the final least count is 0.1 cm/50 = 0.002 cm= 1/50 mm.
Read the vernier as described in the previous section, with a result like 1.4
or 1.6 or 2.0 . A reading of 1.6 from the vernier really means 0.016 cm
which is added to the main scale reading to give the final diameter of
3.216 cm.
3.3 Inside Micrometer
It works on the same principles as that of the outside micrometer and is used for
measuring large diameters say over 50 mm up to an accuracy of 0.01 mm by inserting
extension rods of different lenghts.
The inside micrometer consists mainly of four parts:
a.
b.
c.
d.
Micrometer unit
Extension rod
Spacing collar
Handle
Inside Micrometer
1. Extendsion rod
2. Sleeve
3. Thimble
4. Contact Point
5. Datum Line
The adjustments for reading are made by moving the thimble on the barrel that
works on the principle of the screw. The micrometer screw has a pitch of 0.5 mm and
thimble is having 50 gradations along its circumferences. The least count of an inside
micrometer is also 0.01 mm. the barrel is provided with a scale and reads 13 mm.
The gradations above the reference line are marked in mm and below the
reference line in half mm. When the timble moves through one complete revolution, the
longitudinal distance travelled by it is 0.50 mm or equal to the pitch of thread.
The method of making measurement with an inside micrometer is similar to an outside
micrometer.
Page 3 of 8
Lab 1: Metrology
3.4 Depth Gauge Micrometer
Depth gauge micrometer is also based on the principle of the micrometer. It is similar
in construction to an ordinary micrometer, but instead of a frame, it has a shoulder. The
method of reading si similar to that of micrometers. These micrometers also have an
accuracy of 0.01 mm. A depth gauge micrometer is used for measuring depth of holes in
workshops.
3.5 Vernier Height Gauge
Vernier Height Gauge
A – Fine adjustment nut
B – Vernier Slide
C – Scriber clamp screw
D – Scriber
E – Vernier scale
F – Main scale
G – Base
X,Y – Lock screw
A vernier height gauge consists of a heavy base, a guaranted beam, a sliding head
with vernier sliding jaws holding the scriber and a fine adjustment clamp. Vernier height
gauges are available in sizes of 20 to 250; 30 to 300 mm; 40 to 500 mm; 60 to 800 mm
and 60 to 1000 mm. It is similar to large vernier calipers in construction, except that it
consists of a heavy base which allows the gauge to stand upright instead of a fixed jaw in
a vernier. The movable jaw of vernier height gauge consists of a projection or extension
which is levelled to a sharp edge for scribing lines at any required height.
Page 4 of 8
Lab 1: Metrology
3.6
Dial Indicator
It is also called a test indicator. It is frequently used in machine
shops for turning and aligning machine tools, work and fixtures.
It is also used to test and inspect size and trueness of finished
work, to compare measurements like heights and depth up to an accuracy
of 0.01 mm. It consists of pointer a graduated dial enclosed in a casing
and a plunger projecting at the bottom.
The mechanism of dial indicator is similar to the mechanism used
in pressure and vacum gauges. The plunger requires a very light pressure
for vertical movement and when the plunger moves, the pointer also
moves on the graduated dial. The movement of the contact pointer is
greatly amplified by means of a rack and pinion to get accurate readings.
The least count of a dial indicator is 0.01 mm. The dial gauge can be
brought to any position by totating the zero adjustment generally the first reading is kept
at zero to facilitate other reading. The dial gauge consists of two pointers. When the main
pointer completes one revolution, the small pointer moves by one graduation i.e.,
movement of 1 mm of the plunger pin.
4.0
PROCEDURES
1. Perform a group of five students.
2. Each group will take 4 different specimens.
3. By using the measuring equipments provided, measure all the dimensions of the
specimen that is depth, outer diameter, inner diameter, length, and width.
4. Repeat all the steps with the other 3 specimens.
Further details will be inform later in workshop session.
Page 5 of 8
Lab 1: Metrology
LAB 1
METROLOGY
Lab Result
GROUP NUMBER
:___________________________
DATE OF EXPERIMENT :___________________________
NAME
:___________________________
MATRIC NUMBER
:___________________________
5.0
RESULT*
1. Please fill table below
Rule
mm
inch.
Vernier Caliper
mm
inch.
Micrometer
mm
inch.
Metal Plate
Length
Width
Depth
Straight Coupling
Length
Inside Diameter
Outside Diameter
Thickness
Metal Rod
Diameter
Length
Coin
Diameter
Thickness
Page 6 of 8
Lab 1: Metrology
6.0
QUESTION**
1. What are the technical limits to measurement with the vernier caliper and micrometer?
Give 2 factors that could affect the experiment results?
2. Give the definition of the terms and you may also include figures to explain:
a. Accuracy
b. Precision
c. Tolerance
d. Fit
e. Allowance
Page 7 of 8
Lab 1: Metrology
7.0 DISCUSSION**
(Describe what have you observed and understand during conducting experiment.
Comment about the results, and also give your reason and opinion to this experiment)
8.0 CONCLUSION**
(Based on the data and discussion, make your overall conclusion)
FINAL SCORE : _______ x ______ % = _______
Authorized Signature : ______________
Date : ___________
Page 8 of 8
Lab 2: Sheet Metal Forming
LAB 2
SHEET METAL FORMING
1.0
OBJECTIVE
To expose to the techniques of shaping metal in the processes of cutting, bending, and
folding, either with the used of hand tool or by use of specific machine.
2.0
INTRODUCTION
The sheet metal shop is very important for every engineering concern. It deals
with the working of metal sheets. It requires a thorough knowledge of projective
geometry particularly the development of surfaces because the laying out of pattern and
cutting of metal sheets to correct sizes and shapes entirely depends upon the knowledge
of the workman. The various operations performed in a sheet metal shop are cutting,
shearing, bending etc. In this chapter, we shall discuss the sheet metal tools and the
various processes.
3.0
METALS USED IN SHEET METAL WORK
The following metals are generally used in sheet metal work :
Black iron sheet
It has a bluish-black appearance and is often referred to as uncoated sheet. Since it
is uncoated, therefore, it corrodes rapidly. The use of this metal is limited to
articles that are to be painted or enameled such as stove pipes, tanks and pans.
Galvanised iron
It is a soft steel coated with molten zinc. The zinc coating resists rust, improves
the appearance of the metal, and permits it to be soldered with greater ease. The
galvanised iron sheet is used extensively in fabricated products such as pans,
buckets, furnaces, heating ducts, cabinets, gutters and in many other articles.
Copper
It is a reddish coloured metal and is extremely malleable and ductile. It is used
extensively in the electrical field. Since it does not deteriorate rapidly when
exposed to the atmosphere, therefore, this metal is employed frequently in the
building trades for water pipe, roofing, gutters and other parts of buildings.
Aluminium
It is a silvery white coloured metal and has many qualities like high ratio of
strength to weight, corrosion resistant qualities and ease in fabrication. Now-adays it is used in the manufacture of number of products such as household
appliances, refrigerator trays, lighting fixtures windows, duct work, in
construction of airplanes, in the building trades, and in many electrical and
transportation industries.
Page 1 of 21
Stainless steel
It is an alloy steel possessing the ability to resist corrosion without any surface
coating. One important type of stainless steel contains 18 percent chromium and 8
percent nickel This steel is commonly known as 18/8 steel. It is widely used in
building stream lined trains, food handling equipments, kitchenwares and in many
other applications which require great strength and resistant to corrosion.The
stainless steel sheets can be formed, bent, drilled and soldered in the same manner
as other types of sheet metal. Since stainless steel has greater tensile strength and
hardness, therefore, sheets of this metal are slightly more difficult to work.
Tin plate
It is a steel sheet coated with pure tin. This metal has a very bright silvery
appearance and is used principally in making food containers, cans and pans.
Teme plate
It is a thin steel coated with a mixture of molten tin and lead. This metal has dull
appearance and is used for roofing and tanks. Since the lead coating is poisonous,
therefore, it should not be used for containers that are to hold foods.
Note : The thickness of the metal sheets is indicated by series of numbers called
gauge numbers. Each gauge designates a definite thickness. The thickness of
sheet in inversely proportional to gauge number i. e., larger the gauge number,
lesser is the thickness.
4.0
SHEET METAL TOOLS
The tools commonly used in sheet metal work are as follows :
4.1 Rules
The rules are available in a variety of lengths and types, each of which is
designed for measuring and laying out different work. The following rules are generally
used in sheet metal shop:
(a) Steel rule, folding rule and steel tape. The steel rule (30 cm long), is
particularly useful in measuring and laying out small work. The folding rule (2
metres long) and the steel tape respectively are very helpful in measuring and
laying out large work. In order to measure accurate distance, the rule should be
placed on its edge so that the graduations are in actual contact with the metal.
(b) Circumference rule.
The circumference rule is also used for measuring,
laying out or as a straight edge. In addition to this, the rule also shows the
circumference of circles. The top edge is graduated in centimeters for regular
measuring and the lower half is graduated to indicate circumferences.
Page 2 of 21
4.2 Steel square
It is a L-shaped piece of hardened steel with graduation marks on the edges for
measuring. The narrow arm of the square is called the tongue and the wide part is known
as the body.
4.3 Swinging blade protractor
The swinging blade protractor, used in sheet metal work are made of steel. These
are used for marking or measuring angles.
4.4 Straight edge
It is a flat bar of steel with a bevelled edge. This bar comes in a variety of lengths
ranging from 1 metre to 3 metre. It is useful for drawing long lines.
4.5 Scratch awls or scribers
They are used to scribe or mark lines on a metal surface for a variety of purposes
in laying out patterns. The following are the three common types of scratch awls.
(a) Ring scratch awl. It is a solid steel rod about 5 mm in diameter and 150
mm to 200 mm long. It has a sharp tapered point at one end and a ring at
the other end.
(b) Socket scratch awl. It has a steel blade about 150 mm and provided
with a replaceable wooden handle.
(c) Shank type scratch awl. For general purposes, this type of scratch awl
is preferred by most sheet metal workers because the steel blade passes
through the handle which reinforces the top.
4.6 Dividers
The dividers are made with each leg tapered to a needle point. The two types of
the dividers are the spring divider and the wing divider as shown in Fig. 17.5(a) and (b)
respectively. The legsof the spring divider are adjusted by turning the knurled nut. The
adjustment, on the wing divider is made by loosening the screw on the wing and then
tightening the knurled nut on the end of the wing.
The dividers are available in number of sizes and types. These are used to space off equal
distances, to divide lines into equal parts and to draw arcs and circles.
Trammel points. The trammel points (sometimes called a beam compass), as shown in
Fig. 17.6, consists of two straight, removable legs tapered to needle points and attached to
separate heads or holders. These heads or holders slide on wood or steel bars or beams
and are held in place by thumb screws. A special clamp for a pencil can be attached to
one of the points. The trammel points are used to draw large arcs and circles that are
beyond the limit of dividers.
Page 3 of 21
4.7 Punches
The various hand punches commonly used in sheet metal shop are as follows :
(a) Prick punch. The prick punch, is a tool steel rod whose one end has a tapered
point ground to approximately an included angle of 30°. It is used for making
small indentations or establishing points for dividers and trammel points.
(b) Centre punch. The centre punch, is similar to prick punch, but its point is
ground to an angle of approximately 90°. It is used to mark the location of bend
lines on heavy metal and to mark the centres of holes to be drilled.
(c) Solid punch. The solid punch, is used for punching small holes in thin metal
sheets.
Punchs
(d) Hollow punch. The hollow punch, is used for punching holes upto 10 mm or
above from metal sheets. The inner and outer faces of the punch meet at an angle
of 40°. In order to avoid clipping the edges of the hollow punch, the metal sheets
should be placed over a block of lead.
(e) Hand lever punch. A hand lever punch, is sometimes used for making holes
when too much holes are to be punched. The tool consists of a punch and die and
is operated by hand. The die and punch may be replaced depending upon the size
of the hole required.
4.8 Chisels
The cold chisels are used to cut or shear metal. It is made from a piece of high
carbon or alloy steel of hexagonal or octagonal in shape. There are many different types
of chisels, but the flat chisel, is mostly used for cutting sheet metal, rivets, bolts and in
chipping operations. The flat chisel has a tapered end with a sharp cutting edge which is
properly hardened and tempered. The edge is bevelled to an angle of 40° to 45° for
cutting sheet metal. The cutting edge is also ground to a slight curve to prevent the chisel
from 'digging in' at the comers of metal being cut.
Page 4 of 21
Chisels
4.9 Snips
The snips are somewhat similar to a pair of scissors but are considerably heavier.
There are several types of snips available for making straight or circular cuts, but the
most common are the straight snips and the curved snips.
The straight snips, have straight blades for straight line cutting. These snips may be
obtained in various sizes.
Snips
The curved snips, as shown in Fig, have curved blades for making circular cuts. They are
available for either right hand or left hand cuts.
4.10 Hammers
The hammers, in sheet metal work, are used for forming shapes by hollowing,
raising, stretching or throwing off processes. There are many types of hammers, but the
most commonly used hammers, in sheet-metal work, are as follows :
(a) Balipe hammer. The ball peen hammer, has a round, slightly curved face and a
round head. It is a general purpose hammer.
b) Riveting hammer. The riveting hammer, has a square, slightly curved face with
bevelled edges to prevent the head of the hammer from marking the metal. The
peen side is double tapered and has a slightly rounded end. It is used for spreading
rivets and for hammering a rivet set.
(c) Setting hammer. The setting hammer, has a square, Hat face and a tapered
peen with bevelled end. The flat face is used for flattening seams without damage
to the metal while peen end is used for peening operation.
Page 5 of 21
(d) Hollowing or blocking hammer. The hollowing or blocking hammer, has a
dome face without any sharp comers. It is used for hollowing discs into bowl
shapes.
(e) Raising hammer. The raising hammer, has an oblong flat face with comers
slightly rounded off. It is used in raising circular discs and many other raising and
bumping operations.
Several hammer commonly used in sheet metal process
(f) Planishing hammer. The planishing hammer, has a round face. It is used on
domed circular work.
(g) Collect hammer. The collect hammer, has an oblong shaped faces. It is used
on cylinders and in curved collects.
(h) Tray hammer. The tray hammer, has oval shaped faces. It is used to sink the
bottom when shaping a tray.
4.11 Mallets
The mallets may be made from hide, fibre or wood. The best size of mallet is 5
cm diameter. These may be obtained in various shapes to suit special work.
Several types of mallet
Page 6 of 21
4.12 Pliers
The pliers are used in sheet metal work for holding, cutting and bending work.
The various types of pliers commonly used are as follows :
(a) Flat nose plier. The Hat nose plier, flat jaws with small grooves. It is used for
forming and holding work.
Plier
(b) Round nose plier. The round nose plier, has long jaws rounded on the outside.
It is used for holding and forming the various shapes and patterns.
(c) Slip-joint combination plier. The slip-joint combination plier, has an
adjustable jaw. It is a general purpose tool.
4.13 Hacksaws and files
The hacksaws and files used in sheet metal shop are similar to those used in bench
work and fitting.
5.0
SHEET METAL OPERATIONS
The following are the various sheet metal operations :
1. Marking; 2. Cutting ; 3. Notching; 4. Bending; 5. Riveting ; 6. Soldering ; 7.
Folding edges; 8. Seam making; 9. Hollowing or blocking; 10. Sinking; 11.
Raising; and 12. Planishing.
5.1 Marking
The marking out operation consists of scratching of lines on the surface of a sheet
metal. It is also called scribing operation. Before marking operation is carried out, the
paper or metal pattern of the object is prepared. The metal pattern is desireable for
repetitive work because it maintains accuracy for a long time, whereas the paper pattern
tears quickly if used repeatedly. The pattern is now transferred to the flat sheet metal and
marked as discussed below :
Page 7 of 21
1. When a paper or metal pattern is transferred to the hat sheet metal, it
should be held in place by weights to prevent the pattern from slipping.
2. A sharp pointed pencil is used to mark the outline of the paper pattern,
whereas a scriber is used for metal pattern. The scriber should not be used
to mark the paper pattern because it will tear the edges of the paper.
3. When a pattern is to be traced on aluminum and stainless steel sheets, a
sharp pointed pencil should be used because the scriber will ruin the finish
of the metal.
4. The best method of transferring the paper pattern to sheet metal is to
mark the ends of all lines by a prick punch through the paper. Then
remove the paper from the metal and joint the all prick points by a scriber
in the proper manner.
Many simple objects can be laid out directly on the sheet metal. Usually, it is better for
the beginner to prepare a paper pattern for objects of complicated design rather than to
layout directly on the sheet metal. Since the paper pattern may be checked by folding it
into the required shape, therefore, unnecessary wastage of material is avoided.
In making a layout directly on the steel metal involves operations such as drawing
straight lines or curved lines and making indentation marks to serve as guide for drilling
holes. The procedure for marking straight lines, curved lines and indentation marks is as
follows :
1. Marking straight lines. The straight edge (it is flat bar of steel with bevelled
edge) or a steel square is used to draw straight lines as discussed below :
(a) When a straight edge is used, it is placed on the sheet metal in the
correct position. A sharp pointed scriber is held in one hand at an angle
with the point resting against the edge of the straight edge. Now the line is
drawn by applying a little pressure to the scriber.
(b) When a steel square is used, the body or tongue of square is placed
against the even side of the sheet metal. The scriber is run along the edge
of the tongue or body of the square to mark the straight line.
2. Marking circles and arcs. The circles and arcs on the surface of a sheet metal
are marked with a divider. One leg of the divider is placed at the centre of a circle
or arc to be drawn while the other end is moved with a little pressure on the
divider to mark the circle or arc. The divider is held in one hand. In order to
prevent slipping, the divider is inclined in the direction in which the circle or arc
is drawn. The large circles and arcs are drawn with trammel points.
Page 8 of 21
3. Marking irregular curves. The irregular curves are marked by first laying out a
series of points to indicate the shape of the curve. Now the french curve is set in
such a way that atleast three points coincide with the curve and mark this with a
scriber on the surface of the sheet metal. The french curve is now moved to
coincide next three points and the curve is scribed connecting the first curve. This
process is repeated till the whole curve is marked. The irregular curves may also
be drawn by a flexible rule made of spring steel.
4. Marking indentation marks. The indentation marks are used as locations for
drilling holes, centres for dividers and for transferring a pattern. The indentation
marks for drilling are made with a centre punch, whereas marks for all other
purposes are made with a prick punch. Both the centre punch and prick punch are
used in the same manner. In using these tools, first of all the location of the hole is
marked with two intersecting lines. The punch is held is one hand with its point
directly on the intersection of the two lines. Now strike the head of the punch with
a light blow of the hammer held in other hand.
5.2 Cutting
The sheet metals up to approximately 18 S.W.G. can be cut with hand snips. The
following procedure is adopted for straight cutting.
1. Hold the snip in one hand and the nearest part of the metal in the other hand.
Cutting Technique
2. Open the blades of a snip and place the upper blade on the line of cut to be
followed. The blade should be kept perpendicular to the surface of the metal.
3. Start the cut at the edge of sheet by exerting pressure on handles of snips. When
the cut is about 15 mm from the blade tips, open the blades again and push the
snip forward. Repeat this until cut is completed.
4. As the metal is sheared off, it will curl up on the left hand side of the snips and
curls down on the right hand side of the snips.
5. When cutting a large sheet of metal, it is advisable to cut along the left hand
edge of the sheet to permit the scrap or smaller section to curl away.
Page 9 of 21
6. The inside curves such as circular holes are cut with curved snips. The holes
are first cut roughly with a cold chisel and hammer. It is finally trimmed to the
required size by the curved snip.
7. The outside curves are easily cut with straight snips.
5.3 Notching
In bent sections that have folded edges, there should be some provision so that
there is no overlapping of metal where the comers come together. In order to prevent
bulging at such a place, it is necessary to slit or clip the metal or provide small openings.
The openings left at the comers of seams and edges are known as notches and the
operation is called notching. The size, locations and types of notches depend upon the
shape of object. The following are the different types of notches commonly used in sheet
metal.
1. Straight notch. This notch is prepared by simply making a straight cut where
the bend is to occur. This is used in dovetail seams. The method of laying out
a straight notch.
Straight notch.
2. Square notch. The square notch is used for making a square or rectangular box.
The squares on the comers must be removed to permit the sides to be bent
property.
Square notch.
3. V-notch. The V-notch is used when the corners of a flange must come together.
If the flange forms a right angle, both sides must be cut at an angle of 45°.
Page 10 of 21
V-notch
If the flange is bent at an angle that is less or more than a right angle, the notch
must correspond to the particular angle that is required.
4. Slant notch. When single hems are to meet at right angles, the comers must be
clipped at an angle of 45°.
Slant notch
5. Wire notch. The wire notch is used on an article which has wired edges. This
notch must be provided to prevent the wired edge from overlapping at the
seam. The usual practice is to notch the seam at an angle of about 300, the
angle is started at a point located at a distance from the upper edge of the
pattern equal to approximately 3.5 times the diameter of wire.
Wire notch
Page 11 of 21
5.4 Bending
.
The bending of sheet metal may be done over stakes, blocks of wood pieces of
angle iron or the edge of a bench top. Sometimes the bends can be made in vanous
bending machines. The following procedure may be followed while bending the sheet
metal by hand:
1. First of all, a line is marked with pencil or scriber where the metal is to be
bent. In order to make a right angled bend the sheet is placed on the bench so that
the line is even with the edge at the bench A block of wood is set on the metal
with is edge directly over the bending line. It is then clamped to the bench with Cclamps. In order to bend a small piece of metal, the sheet is placed between two
blocks of wood and then clamped in a vice. The bend is now made by striking the
metal with a mallet using very light blows. The work is started at one end and
finished along the full length of the metal.
2. In order to make a curved bend, the edge of the wooden block is planed to have
the desired curvature. The wooden block is placed even with the edge of the
bench. Another block of the sane thickness is set on the bench top so that the
sheet is in level. Then clamp a piece of angle iron or a hardwood block over the
sheet metal. Now strike the metal with a mallet, gradually bending the sheet over
the curved edge of the block.
3. A tool known as a hand seamer, can be used to make sharp bends on lightgauge sheet metal. Such a tool is especially helpful in bending narrow portions
that are difficult to fold by other methods. This hand seamer has two adjustable
screws which can be regulated for the width of the bend. The metal is simply
placed between the jaws of the seamer and these jaws are clamped together. The
Hat surface of the metal is held firmly with one hand and at the same time the
handle of the seamer is raised. If the metal is longer than the jaws, then small
sections are bent at a time.
5.5 Riveting
It is a process of joining permanently two pieces of sheet metal with rivets. The
special rivets, called tinners' rivets, are used for such a purpose. These rivets are made of
soft iron and are usually coated with tin. This prevents corrosion and makes them easier
to solder. When riveting aluminium, special aluminium rivets should be used. The
following procedure is adopted in making a riveted joint:
1. First of all, drill or punch the holes of correct size. Insert the rivet in the hole
and place the head on some metal bar or stake.
Page 12 of 21
Riveting
2. Place the deep hole of the rivet set over the rivet and strike the rivet set with
few sharp blows. This draws the metal and rivet together. This process is called
drawing process.
3. Remove the rivet set and flatten the e^d of the rivet with the face of a riveting
hammer or ball peen hammer. It should be noted that each blow of hammer
should hit the rivet shank squarely.
4. Place the cup shaped opening of the rivet set over the flattened rivet end, and
strike the rivet set until the head is shaped properly. This process is called heading
process.
5.6 Folding Edges
The edges of the sheet metal may be folded to strengthen the edges and to
eliminate the sharp edges. The three common types of folded edges are single hem,
double hem and wired edges. The single hem is made by turning the edge over the
hatchet stake, and then completed it with a mallet over a flat stake. The double hem is a
single hem with its end bent under.
Folding Edges Techniques
The wired edges are made by bending the sheet with a mallet over a length equal
to Wi times the diameter of wire. This is done on a wooden block whose one edge is
Page 13 of 21
rounded to a radius equal to approximately one half the diameter of the wire. The wire is
now placed in the turned edge and held in position with pliers. The metal is folded over
the wire by striking it with a mallet. The final bend is made by striking the metal with the
peen end of a setting hammer.
5.7 Seam Making
A seam is section where pieces of sheet metal are joined. There are many methods
of making seams, but the type of seam is determined by the thickness of metal, the
purpose for which the object is to be used. The seams commonly used in sheet metal are
as follow;
1. Lap seam
2. Grooved seam
3. Single seam
Page 14 of 21
4. Double seam
5. Dovetail seam
6. Flanged or burred bottom seam
6.0
SHEET METAL MACHINES
A sheet metal shop must be provided with various machines in order to perform
different operations. The machines may be hand operated for working on thin sheets and
power operated for thick sheets. They are also available as either bench or floor models.
Some of the machines commonly used are as follows:
1. Shearing machine
It is used for cutting metal sheets.
2. Folding machine
It is used for bending and folding the edges of the sheet metal.
3. Bending machine
It is used for shaping the metal sheets into cylindrical objects.
4. Grooving machine
It is used for grooving longitudinal seams in cylindrical objects.
5. Forming machine
It is used for forming sheet metal into cylindrical shapes of various diameters.
There are two types of forming machines; i.e., slip-roll forming machine and
plain forming machine, but the former is generally preferred.
6. Beading or swedging machine
It is used to make depressions in metal such as in pipes, machine guards or
wherever reinforcing is necessary.
7. Burring machine
It is used to turn burrs on circular discs such as bottoms and covers. It is also
used for preparing edges for double seaming cylindrical articles.
8. Turning machine
It is similar to a burring machine but differs in the sharpness of the edge it
makes. The burring machine produces a sharp edge, while the turning
machine makes a rounded edge for wiring operations, for bodies of cylinders
and for double seaming.
9. Wiring machine
It is used to complete the metal edge around the wire after the seat to receive
the wire has been prepared by the turning machine.
Page 15 of 21
10. Crimping machine
It is used for crimping (i.e., reducing the diameter of a circular object) and
beading in one pass. The machine may be used only for beading or crimping
by changing the rolls of the machine.
11. Setting-down machine
It is used for setting down seams on containers of various shapes.
12. Double seaming machine
It is used for double seaming flat bottoms on straight or flared cylindrical
pieces.
7.0
1.
2.
3.
4.
5.
6.
7.
8.
8.0
Snips
Mallet
Scratch awls
L square
Steel rule
Protractor
Shearing machine
Aluminium sheets
PROCEDURES
Note: Before start your project, make sure to follow all the safety procedure
Page 16 of 21
Sheet Metal Project for Basic Engineering Skills DCT 100
Tools Box
NOTE :
1. ALL DIMENSIONS ARE IN MILIMETER (mm)
2. DO NOT SCALE THE DRAWING
Prepared by : Mahamad Akmal Bin Hj. Saad & Mohamad Ezral Bin Baharudin
Page 17 of 21
LAB 2
SHEET METAL FORMING
GROUP NUMBER
: ___________________________
DATE OF EXPERIMENT : ___________________________
NAME: ___________________________ MATRIC NUMBER: ________________
:___________________________
9.0
:________________
RESULT*
Your submitted workpiece will be evaluated and concluded as the result.
Grading Reference:
Part 1
Marks
length
/2
height
/2
width
/2
Part 2
length
/2
height
/2
Part 3
length
/2
height
/2
Bending
/10
Assembly
/15
Cleanness
/5
Total
/44
FINAL SCORE : _______ x ______ % = _______
Authorized Signature: ______________
Date: ___________
Page 18 of 21
9.0
RESULT
1. Your finished products will be evaluated by your instructor.
10.0
1.
QUESTION**
In your own words, give the definition of the terms below. You may also include
figures to explain:
a. Bending
b. Shearing
c. Punching
d. Cutoff
2. Describe the process of bending a sheet metal.
Page 19 of 21
3. What is seam? Describe the different types of seams.
11.
DISCUSSION**
Page 20 of 21
12.
CONCLUSION**
FINAL SCORE : _______ x ______ % = _______
Date : ___________
Page 21 of 21
Lab 3: Fitting
LAB 3
FITTING
1.0
OBJECTIVE
Learning to handle all the fitting work equipments, expose to the fitting process and the
tolerance required.
2.0
INTRODUCTION
Most manufactured components are made from several parts which are assembled
together. Accuracy and precision become important when we want to assemble
components together. In designing a component, each dimension needed for the complete
definition of a finished product should be given
3.0
3.1 Vises
Vises are tools used to fix workpieces in place and the size of vises is expressed
by the width of the mouthpieces.
3.1.1 Types of vises
a. Parallel bench vise
This type of vise is used to hold workpieces for many types of hand finishing,
especially filling.
Page 1 of 13
Lab 3: Fitting
b. Leg vise
This type of vise is mainly used for forible work, such as hammering and
chipping.
c. Bench vise
This vise is mostly used for working on a small workpieces.
Note: When holding a finished face between the vise jaws, use protective facings of
copper or aluminium plate, or wood.
Page 2 of 13
Lab 3: Fitting
3.2 Hammers
A hand tool used for striking workpieces. The size of a hammer is expressed by
the weight of the head.
3.2.1 Types of hammers.
•
•
•
•
•
•
•
•
Hand hammer
Sledge hammer
Sheet metal hammer
Chipping hammer
Carpenter’s hammer
Copper hammer
Plastic hammer
Wooden mallet
3.3 Chisels
A hand tool used for chipping and cutting thin sheet metal.
3.3.1 Types of chisels
a. Flat chisel
This is used for flat-surface chipping and for cutting thin sheet, the most common
types of work.
b. Crosscut chisel
This is used for rough chipping and for chipping in grooves and holes.
c. Corner chisel
This is used for chipping oil slots, interior corner and sunken surfaces.
Chisel tip angles and workpiece material.
Tip angle
Workpiece material
0
0
Copper, Lead, White Metal
0
0
Brass, Bronze
25 -30
40 -60
500
Mild Steel
600
0
Cast Iron
0
60 -70
Hard Steel
Page 3 of 13
Lab 3: Fitting
3.4 File
The most commonly used hand-finishing tool. The length of the file (nominal
length) does not include the handle spike length.
3.4.1 Types of file surface
a. Single Cut
Single cut files only have grooves running in one direction, and are used for
filling mild steel and plastic.
b. Double-cut
These are used for general industrial filing.
c. Rasps
These are used to wear away soft materials such as wood, leather and lead.
d. Rippling
Rippled files (vixen files) are used on soft metals such as aluminium and lead.
Page 4 of 13
Lab 3: Fitting
Cut roughness
There are four types of files: rough, medium, fine and extra-fine. Files may be
referred to as rough files and still have different grades: 300 nominal and 150
nominal.
3.4.2 Filing methods
i. Straight filing
File straight forward has a tendency to cause the center to end up higher, unless
you file properly. The final finish work should be done with straight filing.
ii. Diagonal filing
Filing forward while sliding to the right is good for rough filing, because the
amount of material removed is large.
iii. Sideways filing
Holding both ends of the file and sliding it up and down the workpiece is very
difficult to use for a flat surface finish.
3.5 Hacksaw
3.5.1 Types of frames
a. Fixed-length frame
b. Adjustable frame
Fixed-length frame
Adjustable frame
Types of frames
Hacksaw blade selection
Teeth per inch
(25.4 mm)
14 teeth
18 teeth
24 teeth
32 teeth
Material and shape of workpiece
Mild steel, brass
Cast iron, gas pipe
Hard steel, angle irons
Thin iron sheet, thin steel pipe
Page 5 of 13
Lab 3: Fitting
Blade types
Blade types
Blade Dimensions
Total length
Width
Thickness
250
300
12
12
0.64
0.64
Teeth per inch
(25.4 mm)
14, 18, 24,32
“
3.6 Tap
These are hand tool used to manually cut internal threads into holes with tap
attached to a tap handle by its square shank.
Hand Tap
Page 6 of 13
Lab 3: Fitting
Names of tap parts
3.7 Dies
Dies are tools used to cut threads into the outside surfaces of rods and pipes.
Die handle
Page 7 of 13
Lab 3: Fitting
Setup die
Use die handle that fits the outside diameter of the die.
Nominal thread diameter
Die outside diameter
M1M2.6
20
M3M6
25
M8M10
38
M12M16
50
M20
M22
57
63
Notes:
• The diameter of the die thread can be adjusting screw, allowing the same
die to be used for rough cutting and finish cutting.
• The front of the die is the side where the chamfered part is longer, and
usually has the die diameter marked on it.
• When cutting the other end of the same rod, it is better to place a split nut
onto the cut end and clamp them into a bench vise to hold the rod without
damaging the threads.
3.8 Hand Reamers
Used to finish off a drilled hole precisely and smoothly. Shanks are square and
designed to fit tap handles. The cutting part of the reamer is about a 1 degree taper
at the tip.
Hand reamer
Page 8 of 13
Lab 3: Fitting
Names of hand reamer parts
Prepared holes for reamers
a. If the amount of material to be removed is too large, cutting resistance will be
great and chip-packing will occur.
b. Is the amount to be removed is too small, the reamer will slip in the hole and
stop reaming.
Standards for material to be removed.
Reamer diameter
Less than 5 mm
5 – 20 mm
20 – 50 mm
More than 50 mm
4.0
1.
2.
3.
4.
5.
6.
7.
5.0
Material to be removed (diameter)
0.1 – 0.2 mm
0.2 – 0.3 mm
0.3 – 0.4 mm
0.4 – 0.6 mm
Hammer
File
L square
Steel rule
Hacksaw
Drill
100mm x 100mm x 6mm flat bar
PROCEDURES
Page 9 of 13
Lab 3: Fitting
Fitting Project for Basic Engineering Skills DCT 100
T-Shape
NOTE :
2. TOLERANCE ±0.2mm
4. THICKNESS 5mm
Prepared by : Mahamad Akmal Bin Hj. Saad
Page 10 of 13
Lab 3: Fitting
LAB 3
FITTING
Lab Result
GROUP NUMBER
:___________________________
NAME
:___________________________
MATRIC NUMBER
:___________________________
6.0
RESULT
1. Your finished products will be evaluated by your instructor.
7.0
QUESTION**
1.
What is the different between mallet and hammer? You may also include figures
to explain.
Page 11 of 13
Lab 3: Fitting
2. Name and explain various types of files. You may also include figures to explain.
3. Sketch the two types of hacksaw frames and explain their working.
4. Explain the following equipments.
a) Reamers
b) Taps and dies
Page 12 of 13
Lab 3: Fitting
8.0
DISCUSSION**
9.0
CONCLUSION**
FINAL SCORE : _______ x ______ % = _______
Date : ___________
Page 13 of 13
Lab 4: Welding
LAB 4
WELDING
1.0
INTRODUCTION
Welding may be defined as the process of joining similar metals by the
application of heat, with or without the application of pressure and filler metal, in such a
way that the result is a continuity of homogenous material. The welded component results
in continuity of a homogeneous material having the same composition and characteristics
as the two parts to be joined together.
2.0
ADVANTAGE OF WELDING
Welding has the following advantages.
1. It produce a permanent joint
2. The overall cost of welding equipment is generally low.
3. Many portable welding instruments are available.
4. A large number of metals can be welded.
5. A good weld is as strong as the base metal.
6. Welding can be employed from limited portion to any length.
7. Welding operations can be mechanised for production.
3.0
DISADVANTAGE OF WELDING
1.
2.
3.
4.
Welding creates residual stresses and distortion in workpieces.
Edge preparation is generally required before welding.
A skilled welder is essential for performing a good welding operation.
Since welding prodeuces internal stresses, the workpiece often requires
annealing or stress-relieving.
5. Welding produces structural, physical and chemical changes.
6. Jigs and fixtures are needed to hold parts in position.
7. Welding gives off harmful radiations like light, fumes and spatters.
4.0
SAFETY REGULATIONS
You, as the welder, must have a thorough knowledge of the safety precautions
relating to the job. That is not all; you should also consider it your responsibility to
observe all of the applicable safety precautions. When welding, carelessness can cause
serious injury to your-self as well as others.
Bear in mind the safety precautions for operating welding equipment can vary
considerably because of the different types of equipment involved; therefore, only
general precautions on operating metal arc-welding equipment are presented here. For
specific instructions on the operation and maintenance of your individual equipment,
consult the equipment manufacturer’s instruction manual. In regards to general
Page 1 of 15
Lab 4: Welding
precautions, know your equipment and how to operate it. Use only approved welding
equipment, and ensure that it is maintained properly.
•
•
•
•
•
•
5.0
Before you start welding, ensure that the welding machine frame is grounded,
that neither terminal of the welding generator is bonded to the frame, and that
all electrical connections are secure. The ground connection must be attached
firmly to the work, not merely laid loosely upon it.
Keep welding cables dry and free of oil or grease.
Keep the cables in good condition and always take appropriate steps to protect
them from damage. When it is necessary to run cables some distance from the
ma-chine, lay them overhead, if at all possible, using adequate support
devices.
When you are using portable machines, make sure that the primary power
cable is separate from the welding cables so they do not become entangled.
Any portable equipment mounted on wheels should be securely blocked to
prevent accidental movement during welding operations.
When stopping work for any appreciable length of time, be sure to deenergize the equipment. When the equipment is not in use, you should
completely disconnect it from its source of power.
Keep the work area neat and clean. If at all possible, make it a practice to
dispose the hot electrode stubs in a metal container.
TYPES OF WELDED JOINTS
5.1 Lap Joint
The lap joint is obtained by over lapping the plates and then welding the edges of
the plates. These joints are employed on plates having thickness less than 3 mm. The lap
joints may be
a. Single transverse
b. Double transverse
c. Parallel lap joints
Lap Joint
Page 2 of 15
Lab 4: Welding
5.2 Butt Joint
The butt joint is obtained by welding the ends or edges of two plates which are
approximately in the same plane with each other. In butt welds, the plate edges do not
require bevelling if the thickness of plate is less than 5 mm. On the other hand, if the
plate thickness above 12.5 mm should have a V or U-groove on both sides.
The butt joints may be
a. Square butt joint
b. Single V-butt joint
c. Double V-butt joint
d. Single U-butt joint
e. Double U-butt joint
Butt Joint
5.3 Corner joint
The corner joint is obtained by joining the edges of two plates whose surfaces are
at angle of approximately 900 to each other. Is used for both light and heavy gauge
sheet metal. In some cases corner joint can be welded, without any filler metal by
melting off the edges of the parent metal.
Corner, Edge and T- Joint
5.4 Edge joint
The edge joint is obtained by joining two parallel plates. It is economical for plate
having thickness less than 6 mm. This joint is unsuitable for member subjected to
direct tension or bending.
5.5 T-joint
The T-joint is obtained by joining two plates whose surfaces are approximately at
right angles to each other. It is widely used to weld stiffeners in air craft and other
thin walled structures. These joints are suitable up to 3 mm thickness.
Page 3 of 15
Lab 4: Welding
6.0
GAS WELDING
It is a non-pressure fusion welding process and includes all process in which gas
is used as a source of heat to melt the ends of the pieces to be joined on solidification. A
filler metal is needed in welding of sheets above 1.5 mm thickness but no filler metal is
needed for welding below 1.5 mm thickness. A filler metal is added in the form of a filler
rod must be having the same composition as that of the parent metal.
The oxy-acetylene flame is most widely used as it produces very high
temperatures (35000) and can be used for welding of a variety of ferrous and non-ferrous
materials. It forms an inert gas envelop over the surface and the flame is easily
controllable.
The disadvantage of oxy-acetylene flame is that different blow pipes are needed
for different operations. Each operation also requires different pressure of gases.
6.1 Oxygas Welding Equipment
An oxygas welding outfit is basically the same as an oxygas cutting outfit with the
exception of the torch. The welding outfit usually consists of a cylinder of acetylene or
MAPP gas, a cylinder of oxygen, two regulators, two lengths of hose with fittings, and a
welding torch with tips. An oxygas welding outfit also is called a welding rig.
In addition to the basic equipment
mentioned, you also use the same
auxiliary equipment that was discussed
in and earlier lesson. This equipment
consists of tip cleaners, cylinder trucks,
clamps, and holding jigs. Safety
apparel, which includes goggles, hand
shields, gloves, leather aprons, sleeves
and leggings, is essential and should be
worn as required.
Oxygas welding equipment, like cutting
equipment, may be stationary or
portable. A portable oxygas outfit, is an
advantage when it becomes necessary
to move the equipment.
To perform your welding duties, you must be able to set up the welding equipment and
make the adjustments required to perform the welding operation. Thus it is important that
you understand the purpose and function of the basic pieces of equipment that makeup
the welding outfit.
Page 4 of 15
Lab 4: Welding
6.2 Welding Torches
The oxygas welding torch mixes oxygen and fuel gas in the proper proportions
and controls the amount of the mixture burned at the welding tip. Torches have two
needle valves: one for adjusting the oxygen flow and the other for adjusting the fuel gas
flow. Other basic parts include a handle (body), two tubes (one for oxygen and another
for fuel), a mixing head, and a tip. On some models the tubes are silver-brazed to the
head and the rear end forgings, which are, in turn, fitted into the handle. Welding tips are
made from a special copper alloy and are available indifferent sizes to handle a wide
range of uses and plate thicknesses.
Two general types of welding torches are used:
•
•
Low pressure
Medium pressure
The low-pressure torch is also known as an injector torch. The fuel-gas pressure
is 1 psi (pound per square inch) or less. The oxygen pressure ranges between 10 to 40
pounds, depending on the size of the torch tip. A jet of relatively high-pressure oxygen
produces the suction necessary to draw the fuel gas into the mixing head. The welding
tips may or may not have separate injectors in the tip.
Low pressure and medium pressure torches.
Medium-pressure torches are often called balanced-pressure or equal-pressure
torches because the fuel gas and the oxygen pressure are kept equal. Operating pressures
vary, depending on the type of tip used.
A typical equal-pressure welding torch, also called a general-purpose torch. The
medium pressure torch is easier to adjust than the low-pressure torch and, since equal gas
pressures are used, you are less likely to get a flashback.
Welding TIPS and MIXERS are designed in several ways, depending on the
manufacturer. Some torch designs have a separate mixing head or mixer for each tip size.
Page 5 of 15
Lab 4: Welding
Other designs have only one mixer for several tip sizes. Tips come in various types;
some are one-piece hard-copper tips and others are two-piece tips that include an
extension tube to make the connection between the tip and the mixing head. When used
with an extension tube, removable tips are made of hard copper, brass, or bronze. Tip
sizes are designated by numbers, and each manufacturer has his own arrangement for
classifying them. Tip sizes differ in the diameter of the hole.
6.3 Filler Rods
The term filler rod refers to a filler metal used in gas welding, brazing, and certain
electric welding processes in which the filler metal is not a part of the electrical circuit.
The only function of the filler rod is to supply filler metal to the joint. Filler rod comes in
wire or rod form that is often referred to as “welding rod.”
As a rule, filler rods are uncoated except for a thin film resulting from the
manufacturing process. Filler rods for welding steel are often copper-coated to protect
them from corrosion during storage. Most rods are furnished in 36-inch lengths and a
wide variety of diameters, ranging from 1/32 to 3/8 inch. Rods for welding cast iron vary
from 12 to 24 inches in length and are frequently square, rather than round. You
determine the rod diameter for a given job by the thickness of the metal you are joining.
Except for rod diameter, you select the filler rod based on the specifications of the metals
being joined.
Many different types of rods are manufactured for welding ferrous and nonferrous
metals. In general, welding shops stock only a few basic types that are suitable for use in
all welding positions. These basic types are known as generalpurpose rods.
6.4 Oxygas Welding Technique
Oxygas welding maybe done using either the forehand or
the backhand method. Each of these techniques has special
advantages and you should become skillful with both. The
deciding factor that determines whether a technique is considered
forehand or backhand is the relative position of the torch and rod
during welding, not the direction of welding. The best method to
use depends upon the type of joint, joint position, and the need
for heat control on the parts to be welded.
Page 6 of 15
Lab 4: Welding
6.5 Forehand Welding
Forehand welding is often called PUDDLE or RIPPLE WELDING. In this method
of welding, the rod is kept ahead of the flame in the direction in which the weld is being
made. You point the flame in the direction of travel and hold the tip at an angle of about
45 degrees to the working surfaces. This flame position preheats the edges you are
welding just ahead of the molten puddle. Move the rod in
the same direction as the tip, and by moving the torch tip
and the welding rod back and forth in opposite, semicircular
paths, you can distribute the heat evenly. As the flame
passes the welding rod, it melts a short length of the rod and
adds it to the puddle. The motion of the torch distributes the
molten metal evenly to both edges of the joint and to the
molten puddle.
The forehand method is used in all positions for
welding sheet and light plate up to 1/8 of an inch thick. This method is ideal because it
permits better control of a small puddle and results in a smoother weld. The forehand
technique is not recommended for welding heavy plate due to its lack of base metal
penetration.
6.6 Backhand Welding
The torch tip pre-cedes the rod in the direction of welding and the flame points
back at the molten puddle and completed weld. The welding tip should make an angle of
about 60 degrees with the plates or joint being welded. The end of the welding rod is
placed between the torch tip and the molten puddle.
Less motion is used in the backhand
method than in the forehand method. If you use
a straight welding rod, you should rotate it so
the end rolls from side to side and melts off
evenly. You might have to bend the rod when
working in confined spaces. If you do, it
becomes difficult to roll a bent rod, and to
compensate, you have to move the rod and
torch back and forth at a rather rapid rate.
When making a large weld, you should move
the rod so it makes complete circles in the
molten puddle. The torch is moved back and
forth across the weld while it is advanced
slowly and uniformly in the direction of the
welding.
Page 7 of 15
Lab 4: Welding
The backhand method is best for welding material more than 1/8 of an inch thick.
You can use a narrower vee at the joint than is possible in forehand welding. An included
angle of 60 degrees is a sufficient angle of bevel to get a good joint. The backhand
method requires less welding rod or puddling as the forehand method.
By using the backhand technique on heavier material, you can increase your
welding speed, better your control of the larger puddle, and have more complete fusion at
the weld root. If you use a slightly reducing flame with the backhand technique, a smaller
amount of base metal is melted while welding the joint. When you are welding steel with
a backhand technique and a slightly reducing flame, the absorption of carbon by a thin
surface layer of metal reduces the melting point of the steel. This speeds up the welding
operation, This technique is also used in surfacing with chromium-cobalt alloys.
6.7 Joint Edge Preparation
Sheet metal is easily melted and does not require special edge preparation. In
welding operations involving plate, joint edge preparation and proper spacing between
edges are important factors. The thickness of the plates determines the amount of edge
preparation required. The faces of square edges can be butted together and welded You
can use this type of joint on plate up to 3/16 of an inch thick. For plate 3/16 to 1/4 of an
inch thick, a slight root opening between the parts is necessary to get complete
penetration. Plate more than 1/4 of an inch thick requires beveled edges and a root
opening of 1/16 of an inch. For oxygas welding on plate more than 1/4 of an inch thick,
bevel the edges at an angle of 30 degrees to 45 degrees, making the groove included
angle from 60 degrees to 90 degrees. You can prepare the edges by flame cutting,
shearing, flame grooving, machining, chipping, or grinding. In any case, the edge
surfaces should be free of oxides, scale, dirt, grease, or other foreign matter.
Plate from 3/8 to 1/2 of an inch thick can be welded from one side only, but thicker
sections should be welded by preparing the edges on both sides. Generally, butt joints
prepared on both sides permit easier welding, produce less distortion, and ensure better
weld qualities.
Heavy steel plate is rarely welded with oxygas unless other types of welding
equipment are not available. The welding of heavy plate is just not cost effective because
of the amount of gas consumed and time used to complete a weld. If at all possible, use a
form of electric arc welding because the joint can be welded faster, cheaper, and there is
less heat distortion.
Page 8 of 15
Lab 4: Welding
7.0
ARC WELDING
The arc welding is a fusion welding process in
which the welding heat is obtained from an electric
arc between the work (or base metal) and an
electrode. The electric arc is produced when two
conductors of an electric circuit are touched together
and then separated by a small distance, such that there
is sufficient voltage in the circuit to maintain the flow
of currrent through the gaseous medium (air). The
temperature of heat produced by the electric arc is of
the order of 60000C to 70000C.
The welding is done by first making contact of
the elctrode with the work and then separating the
electrode toa proper distance to produce an arc. When
the arc is obtained, intense heat so produce quickly
melts the work under the arc forming a pool of molten
metal which seems to be forced out of the pool by the
blast from the arc. A small depression is formed in the
work and then molten metal is deposited around the
edge of this depression, which is called the arc crator.
The slag is brushed off after the joint has cooled. The arc, once started, should be
advanced at a uniform speed along the desired line of welding. The melting should reach
to a sufficient depth below the original surfaces of the metal pieces to be joined to obtain
the desired weld. This is known as obtaining proper penetration.
Page 9 of 15
Lab 4: Welding
Comparison between A.C. and D.C. Arc Welding
1.
2.
3.
4.
5.
6.
7.
8.
A.C. arc welding
The A.C. welding transformer
has no moving parts and is
simpler.
The transformer costs less and
its maintenance cost is low.
Since the distribution of heat is
equal, therefore there is no need
for changing the polarity. Hence
only ferrous metals are usually
welded by A.C.
All types of electrodes can not
be used in A.C. arc welding
because the current constantly
reverse with every cycle. Only
coated electrodes can be used.
The problem of ‘arc blow’ does
not arise as it is very easy to
control.
The arc is never stable.
It can be used only when A.C.
supply from the mains is
available.
A.C. is more dangerous.
1.
2.
3.
4.
5.
6.
7.
8.
D.C. arc welding
The D.C. welding generator has
rotating parts and is more
complicated.
The generator costs more and its
maintenance cost is high.
Heat distribution is different in
two poles, i.e., two-third in
positive and one-third in negative.
By changing the polarity, all types
of metals can be welded by D.C.
All types of electrodes, bare or
coated can be used in D.C. arc
welding because the polarity can
be changed to suit the electrode.
In D.C. the ‘arc blow’ is severe
and cannot be controlled easily.
The arc is more stable.
In the absence of A.C. mains
supply, an engine driven D.C.
generator set can be used.
D.C. is comparatively less
dangerous.
All arc-welding processes have three things in common: a heat source, filler
metal, and shielding. The source of heat in arc welding is produced by the arcing of an
electrical current between two contacts. The power source is called a welding machine or
simply, a welder. This should not be confined with the same term that is also used to
describe the person who is performing the welding operation. The welder (welding
machine) is either electric- or motor-powered.
7.1 Shielded Metal Arc Welding (SMAW)
Shielded metal arc welding is performed by striking an arc between a coatedmetal electrode and the base metal. Once the arc has been established, the molten metal
from the tip of the electrode flows together with the molten metal from the edges of the
base metal to forma sound joint. This process is known as fusion. The coating from the
electrode forms a covering over the weld deposit, shielding it from contamination;
therefore the process is called shielded metal arc welding. The main advantages of
shielded metal arc welding are that high-quality welds are made rapidly at a low cost.
Page 10 of 15
Lab 4: Welding
Basic set up for metal arc welding
7.2 Arc Welding Procedure
An arc welding operation involves the following steps.
1. Throughly clean and prepare the edge for proper deposition of the metal.
2. Select the electrode of proper material (having the same composition as
base metal) and size according to dimension s of the workpiece.
3. Adjust the voltage to proper value.
4. Layout the workpiece and connect with an earth damp.
5. Strike the arc at the correct position.
6. Take a proper run of the welding. If needed take another run of the
welding
7. Clean the weld and chip off the spatter.
7.3 Process capabilities
SMAW commonly used in general construction, in shipbuilding, on pipelines and
for maintenance work, because the equipment is protable and can be easily maintained. It
is specially useful for work in remote areas, where a protable fuel-powered generator can
be used as the power supply. The process is best suited for workpiece thickness of 3 mm
– 19 mm (0.12 in. – 0.75 in.), although this range can be easily extended by skilled
operators using multiple-pass technique.
About 50% all large-scale industrial welding operations use this process
The multiple-pass process requires that the slag can be cleaned after each weld
bead. Unless removed completely, the solidified slag can cause severe corrosion of the
weld area and lead to failure of the weld. Slag should be completely removed, such as by
Page 11 of 15
Lab 4: Welding
wire brushing, before another weld is applied for multiple-pass welding. As a result, both
labor costs and material costs are high.
A deep weld showing the buildup sequence of individual weld beads
8.0
1.
2.
3.
4.
5.
6.
9.0
Properly set up and adjusted arc/gas welding machine.
Proper safety attire such as shoes, safety jackets, safety glasses, gloves, etc.
Welding hood
Wire brush
Chipping hammer
Pliers
PROCEDURE
Page 12 of 15
Lab 4: Welding
LAB 4
WELDING
Lab Result
GROUP NUMBER
:___________________________
NAME
:___________________________
MATRIC NUMBER
:___________________________
10.0
RESULT*
Your submitted workpiece will be evaluated and concluded as the result.
1) Arc Welding
Bead
T-Joint
Marks
/10
/10
/10
/10
/10
/10
/10
/10
/10
/10
1
2
3
4
5
1
2
3
4
5
%
/100
2) Gas Welding
Bead
Lap-Joint
Marks
/10
/10
/10
/10
/10
/10
/10
/10
/10
/10
1
2
3
4
5
1
2
3
4
5
%
/100
Grading Reference :
1 – Straight
2 – Width
3 – Height
4 – Arc/Gas of welding
5 – Cleaness
Page 13 of 15
Lab 4: Welding
11.0
QUESTION**
1.
What is gas welding? Why oxy-acetylene welding is preferred over other welding
technique?
2.
Describe the priciple of operation of arc welding?
3.
Give three factors that could affect welding operation?
Page 14 of 15
Lab 4: Welding
12.0
DISCUSSION**
13.0
CONCLUSION**
FINAL SCORE : _______ x ______ % = _______
Date : ___________
Page 15 of 15
Lab 5: Turning Process
LAB 1
LATHE MACHINE
1.0
INTRODUCTION
A lathe is the forerunner of all machines. It is the most important machine used in any
workshop. Initially it was used for wood turning. After Henry Maudslay developed the
sliding carriage in 1800, a lot of development has taken place and lathes are now
available in numerous sizes and shapes.
Figure 1: Component of a lathe
A lathe removes the material by rotating the workpiece against a single point cutting tool.
The part to be machined can be held between two rigid support called centers, or by
some other device such as a chuck or face plate, that is screwed or secured to the end of
the spindle.
Turning means the part is rotating while it is being machined. The starting material is
usually a work piece that has been made by other processes, such as casting, forging,
extrusion or drawing.
Page 1 of 10
2.0
PART OF A LATHE
Bed: The bed of a lathe consists of two heavy parallel sides having ways. It is held rigidly
by cross girths supported by cast iron supports.
Headstock: It is situated at the left-hand and of the bed. It consists of a headstock casing
and supports the spindle and driving arrangement. The steel spindle is hollow, so that the
bars can be passed through it if necessary. The spindle nose of the spindle is threated to
hold the chuck or face plate by screwing it on.
Tailstock: This is a counterpart of the headstock and is located opposite it on the ways of
the bed. It consists of a tapeset hole, adjusting screw and handwheel. It is used for
supporting and feeding drills, reamers and centers.
Carriage: The carriage is a moving part that slides over the ways between the headstock
and the tailstock. It consists of a saddle and apron, and also carries the compound rest.
Feed Rod and Lead Screw: The feed rod is powered by a set of gears from the
headstock. It rotates during the operation of the lathe and provides movement to the
carriage and the cross-slide by means of gears, a friction clutch and a keyway along the
length of the rod. Closing a split nut around the lead screw engages it with the carriage; it
is also used for cutting threads accurately.
3.0
TOOL LIFE
The time for which a tool keeps its machining capacity between two regrinding operations
is known as tool life. It can be estimated by the number of pieces machined between tool
regrinds. Since a considerable time is wasted in tool regrinding and resetting on the
machine, it pays to enhance tool life. To this end, the following factors need to be
considered.
• Cutting speed of the tool. Increased cutting speed decreases tool life.
• The shape of the tool and its angles.
• The ratio of feed and depth of cut.
• The rigidity of the tool, workpiece and machine.
• The nature and quantity of the cutting fluid.
• Tool setting in relation to the workpiece.
• Nature of the material being cut.
• Chemical composition of the tool.
• Heat treatment operations carry out on the tool.
Page 2 of 10
4.0
OPERATION PERFORMED BY A LATHE / TURNING
The following processes are capable of producing a wide variety of shapes:
•
•
•
•
•
•
•
Turning, to produce straight, conical, curved, or grooved workpieces such
as shafts, spindle and pins.
Facing, to produce a flat surface at the end of the part, which is useful for
that parts that are attached to other components, or face grooving to
produce grooves for O-ring seats.
Boring, to enlarge a hole or cylindrical cavity by made by a previous process
or to produce circular internal grooves.
Drilling, to produce a hole, this may be followed by boring to improve its
accuracy and surface finish.
Parting, also called cutting off, to cut a piece from the end of a part, as is
done in the production of slug or blanks for additional processing into
discrete products.
Threading, to produce external or internal threads.
Knurling, to produce a regularly shaped roughness on cylindrical surfaces,
as in maling knobs.
Figure 2: A type of cutting operations that can be performed on a lathe. Note that all parts have
circular symmetry.
Page 3 of 10
Boring
Knurling
Drilling
Figure 3: Illustrations of Boring, Knurling and Drilling operation.
LATHE CUTTING SPEEDS IN METERS PER MINUTES AND
FEET PER MINUTE USING A HIGH SPEED TOOLBIT
TURNING AND BORING
THERADING
MATERIALS
ROUGH CUT
FINISH CUT
m/min
ft/min
m/min
ft/min
m/min
ft/min
MACHINE
STEEL
27
90
30
100
11
35
TOOL
STEEL
21
70
27
90
9
30
CAST IRON
18
60
24
80
8
25
BRONZE
27
90
30
100
8
25
ALUMINIUM
61
200
93
300
18
60
Page 4 of 10
RPM CALCULATION
- RPM = Revolution per minute (rotational speed of the workpiece)
- CS = Cutting Speed
- D
= Diameter (workpiece)
METRIC CALCULATION
RPM = CS x 320
D
5.0
1.
2.
3.
4.
5.
6.
7.
8.
6.0
Workpiece diameter Ø 40 mm x 150 mm
Lathe machine with accessories such as tool post, drill chuck, etc.
Safety attire such as goggles, safety jacket, etc.
Cutting tool
Knurling tool
Grooving tool
Drill
Vernier caliper for measurement
PROCEDURES
1. Measure and mark your workpiece.
2. Open up the chuck jaws slightly larger than the diameter of the workpiece.
3. Insert the workpiece and center the workpiece at the chuck mount and the feed
end.
4. Tighten the workpiece securely
5. Install the tool into the tool rest
6. Determine the main spindle rpm
7. Set the main spindle speed select levers to the closest rpm.
8. Rotate the main spindle forward.
9. Approach the tool tip to the workpiece end, and cut into the end in the spindle axis
direction.
10. Use the scale on the tool rest feed handle to determine cutting depth.
11. Apply (5) to (9) for rough cutting on endface and outside diameter.
12. Consult with your engineers if you facing difficulties.
Note: Before start your project; make sure to follow all the safety procedure
Page 5 of 10
Lathe Machine Project for Basic Engineering Skills DCT 100
Figure 1
NOTE :
4. REMOVE ALL SHARP EDGES
Prepared by : Mohd Nazri Bin Abu Bakar
Page 6 of 10
LAB 5
LATHE / TURNING WORK
Lab Result
GROUP NUMBER
:___________________________
MACHINE NUMBER
:___________________________
GROUP MEMBERS NAME :
1)_________________________________________ Matric No:__________
2)_________________________________________ Matric No:__________
3)_________________________________________ Matric No:__________
4)_________________________________________ Matric No:__________
7.0
RESULT*
1. Your workpiece will be concluded as the result.
NO
1
2
3
4
5
6
7
8
SIZE
Ø28 x 15 (L)
Ø30 x 60 (L)
Ø27 x 50 (L)
Taper 20° x 20 (L)
Sharp Edge
Surface Roughness
Clean the machine, floor and tool rack
Question / Answer
TOTAL
MARKS
/10
/10
/10
/10
/10
/10
/10
/10
/80
Page 7 of 10
8.0
QUESTION**
1. How to calculate Cutting Speeds?
2. Explain in brief, with diagram, how you will perform the following operations on a lathe?
a) Drilling
b) Facing
c) Boring
d) Knurling
Page 8 of 10
9.0
DISCUSSION**
10.0
CONCLUSION**
FINAL SCORE : _______ x ______ % =
_______
Page 9 of 10
Date : ___________
Page 10 of 10
Lab 6: Milling Machine
LAB 6
MILLING MACHINE
1.0
INTRODUCTION
The milling machine, invented by Eli Whitney in 1818, carries out cutting
operation on a workpiece with a revolving cutter as the workpiece is fed against it. A
milling cutter has a series of cutting edge on its circumference. Each acts as an individual
cutter during the cycle of rotation.
Milling Machine
2.0
AUTOMATIC TABLE FEED OPERATION
2.1 Feed speed conversion chart
The speed corresponding to the lever positions are as follows:
Select lever positions
(indicator color)
Low Speed(yellow)
Medium speed (blue)
High speed (red)
Indicator
marking
Feed speed (mm/min)
50 Hz
60 Hz
15 ~ 60
18 ~ 72
60 ~ 240
72 ~ 288
240 ~ 960
288 ~ 1152
Cautions when converting speeds
a. Only move the select levers after the feed motor is stopped
b. Move the variable speed dial with the motor running.
Difference in table movement directions
a. Right-left and front-back movement is as written on the variable speed dial.
b. Up-down movement is 1/3 of the numbers on the variable speed dial.
Page 1 of 11
2.2 Main spindle rpm
There are 12 main spindle speeds, as shown in the table.
H
L
900
320
113
40
1267
453
161
57
1800
638
227
80
2.3 Types of milling machines
There are two main types of milling machines: a general purpose milling machine
and a production milling machine.
a. General purpose milling machine – designed for multi-type, small lot milling
and knee type
b. Production milling machine – designed for heavy cutting and is bed type.
There are also milling machines with the spindle vertical, or horizontal.
3.0
MILLING CONDITIONS
The milling conditions are the cutting speed, the feed rate and the cutting depth. These
vary with the type of cutting type of cutting head, cutting head material and workpiece
material.
3.1 Cutting speed
The relation between cutting speed and main spindle speed is as follow:
Where v = cutting speed (m/min)
d = cutter diameter (mm)
N = main spindle rpm.
3.2 Feed rate
The feed value is expressed in terms of one blade, but the feed rate for milling is
in terms of the table speed.
Where T = table speed (mm/min)
f = speed in mm/blade
N = main spindle rpm
Z = number of blades.
The calculated cutting conditions for a face milling cutter (150 dia., 10 cutting
chips) and an end mill (12 dia., 2 blades), where v = 100 ~ 120 and 20 ~30
m/min., and f = 0.15 mm./ blade and 0.075 mm./blade are as follow:
Page 2 of 11
Mill type
Cutting Conditions
Rough
rpm
Machining
Feed rate
Finish
rpm
Machining
Feed rate
Face milling cutter
Dia 150
Dia 150
200
240
300
360
240
300
180
230
End mill HS
Dia 12
540
Manual Feed
540
50
3.3 Cut depth
For workpieces with mil scale, the rough cut should be 2 mm. deep and the finish
cut 0.3 ~ 0.5 mm.
The maximum cut depth with an end mill should be the diameter of the end mill.
4.0
MILLING OPERATIONS
Milling includes a number of highly versatile machining operations capable of
producing a variety of configurations with use of a milling cutter, a multitooth
tool that produces a number of chips in one revolution. Parts can be machined
efficiently with various types of milling cutters.
Some of the basic types of milling cutters and milling operation
4.1 Slab Milling
In a slab milling, also called peripheral milling, the axis of cutter rotation is
parallel to the workpiece surface to be machined. The cutter, generally made of
high-speed steel, has a number of teeth along its circumference, each tooth acting
like a single-point cutting tool called a plain mill.
Page 3 of 11
4.2 Conventional Milling and Climb Milling
In conventional milling, also called up milling, the maximum chip thickness is at
the end of the cut. In climb milling, also called down milling, cutting starts at the
surface of the workpiece, where the chip is at its thickest.
(a) Schematic illustration of conventional milling and climb milling.
(b) Slab milling operation, showing depth of cut,d, feed per tooth,f, chip depth of cut,tc,
and workpiece,v.
(c) Schematic illustration of cutter travel distance lc to reach full depth of cut.
4.3 Face Milling
In face milling, the cutter is mounted on a spindle having an axis of rotation
perpendicular to the workpiece surface. When the cutter rotates, the operation is
climb milling; when it rotates in the opposite direction the operation is
conventional milling. The cutting tools are mounted on the cutter body.
Face milling operation showing
(a) action of an insert face milling (b) climb milling
(c) conventional milling (d) dimension in face milling
Page 4 of 11
The relationship of cutter diameter and insert angles and their position relative to
the surface to be milled is important in that it will determine the angle at which an
insert enters and exits the workpiece. For climb milling that if the insert has zero
axial and radial rake angle, the rake face of the insert engages the workpiece
directly.
Terminology for a face-milling cutter.
(a) Relative position of the cutter and insert as it first engages the workpiece in face
milling
(b) insert positions toward the end of cut, and
(c) example of exit angles of insert, showing desirable (positive or negative angle) and
undesireble (zero angle) position.
Page 5 of 11
4.4 End Milling
Flat surface as well as various profiles can be produced by end milling. The cutter
in end milling (end mill); it has either straight or tapered shanks for smaller and
larger cuter sizes, respectively. The cutter usually rotates on an axis perpendicular
to the workpiece, although it can be tilted to machine-tapered surfaces.
Cutters for (a) straddle milling (b) form milling (c) slotting and
(d) slitting with a milling cutter.
4.5 High-Speed Milling
One of the more common applications is high-speed milling using an end mill,
which observe the same general provisions regarding the stiffness of machines,
workholding device, etc. A typical application is the milling of aluminium-alloy
aerospace components and honeycomb structures, with spindle speeds on the
order of 20,000 rpm. Chip collection and disposal can be a significant problem in
these operations.
5.0
1.
2.
3.
4.
5.
6.
7.
Mild Steel Block (18 mm x 28 mm x 150 mm)
Vernier Calliper
Inside Micrometer
Fine flat file
Copper hammer
Levelling stand
Rough brush
Page 6 of 11
6.0
PROCEDURES
1.
2.
3.
4.
Remove workpiece burrs with the file
Check the workpiece measurements with the calipers.
Attach the protective plate to a vise jaw
Place the workpiece and levelling stands in the vise jaws so that the workpiece is
level.
5. Determine the main spindle rpm and set the rpm to the nearest value.
6. Determine the table feed rate.
7. Move the workpiece to the center of the cutter
8. Set the knee scale to 0, and then drop the workpiece by a ¼ turn of the scale.
9. Move the table to the left and set the cut depth to 1 mm.
10. Using manual feed, machine the workpiece. When finished, drop the knee and
return the workpiece to the original position.
11. Stop the main spindle and check that the machined surface looks normal.
12. Apply (5) to (9) for the next process.
13. Consult with your engineers if you facing difficulties.
Page 7 of 11
Milling Machine Project for Basic Engineering Skills DCT 100
Base Block
NOTE :
4. REMOVE ALL SHARP EDGES
5.
DRILL 2 RELIEF HOLES Ø5mm
Prepared by : Mahamad Akmal Bin Hj. Saad
Zainul Abidin Bin Ramli
Page 8 of 11
LAB 6
MILLING MACHINE
Lab Result
GROUP NUMBER
:___________________________
MACHINE NUMBER
:___________________________
GROUP MEMBERS NAME :
1)_________________________________________ Matric No:__________
2)_________________________________________ Matric No:__________
3)_________________________________________ Matric No:__________
4)_________________________________________ Matric No:__________
7.0
RESULT*
1. Your workpiece will be concluded as the result.
NO
1
2
3
4
5
6
7
8
9
10
SIZE
Surface Roughness
Sharp Edge
Clean the machine, floor and tool rack
Question / Answer
TOTAL
MARKS
/10
/10
/10
/10
/10
/10
/10
/10
/10
/10
/100
Page 9 of 11
8.0
QUESTION**
1. Explain the working principle of a milling machine?
2. Describe briefly the main functions of a
a) Horizontal milling machine
b) Vertical milling machine
Page 10 of 11
7.0 DISCUSSION**
8.0 CONCLUSION**
FINAL SCORE : _______ x ______ % = _______
Date : ___________
Page 11 of 11

DCT100 Laboratory Module

Transcription

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