Machining Lithophanes

Machining Lithophanes
with
Tutorial 2
Getting Started
PhotoVCarve
Disclaimer
All CNC machines (routing, engraving, and milling) are potentially dangerous and because Vectric Ltd has no
control over how the software described in this manual might be used. Vectric Ltd or any associated Resellers
cannot accept responsibility for any loss or damage to the work piece, machine or any individual, howsoever
caused by misusing the software. Extreme care should always be taken and the output from the software
thoroughly checked before sending it to a CNC machine.
The information in this manual may be subject to change without any prior notice. The software described in
this manual is supplied under the terms and conditions of the software license agreement and may only be
used in accordance with the terms of this agreement.
© Vectric Ltd
26 Peterbrook Close
Redditch
B98 7YF
UK
www.vectric.com
E-mail info@vectric.com
Phone +44 (0) 1527 460 459
Fax +44 (0) 1527 460 459
Table of Contents
What is a Lithophane? ...................................................................................... 2
What file formats can be used? ........................................................................ 2
Watch the supporting tutorial videos................................................................. 3
Tutorial 1
Machining Lithophanes ............................................................ 4
Introduction ....................................................................................................... 4
1.
Opening Image......................................................................................... 5
3.
Calculate a Roughing Toolpath ............................................................... 7
4.
Save the Toolpath ................................................................................... 8
Running the Toolpath .............................................................................. 8
5.
Calculate a Finishing Toolpath ................................................................ 9
6.
Save the Toolpath ................................................................................. 10
Running the Toolpath ............................................................................ 10
Introduction
This short tutorial explains how to convert a photograph into a Lithophane using PhotoVCarve.
What is a Lithophane?
Lithophanes are translucent pieces of material that look 3D when lit from the back. This is a very old
technique that was originally used to make ceramic or porcelain products such as lamp shades, beer steins and
window decoration.
Materials that are suitable and commonly used for making lithophanes include Corian, Avenite, Plexi-glass,
Perspex or any other translucent material allows light to pass through when it's only 0.08” – 0.120” (2mm or 3
mm) thick.
Important - The process will not work with totally transparent or solid materials such as metals
It is possible to make a mold and cast Lithophanes from Ceramics to achieve the required effect.
Back Lit Lithophane
What file formats can be used?
PhotoVCarve will open photographs that have been saved in the following formats.
JPG, BMP, TIF, PNG, GIF
2
Watch the supporting tutorial videos
›
This tutorial has an associated video file that will make learning to use this software more interesting
and enjoyable. This file can be downloaded from the web site. Windows Media Player is required to view the
video files.
The video Tutorial shows how to calculate roughing and finishing toolpaths for machining the photograph of
the Cute Puppies to make a Lithophane.
If you experience problems or have any questions pleasevisit the Vectric web site, the User Forum or
e-mail the Vectric Support Team,
support@vectric.com
3
Tutorial 1
›
Machining Lithophanes
We recommend that you watch the 5 minute Video for this Tutorial before proceeding. The video
can be downloaded from the web site at www.vectric.com
Introduction
This tutorial will show you how to calculate toolpaths to machine a Lithophane from a picture. The design is
8” x 6” wide and will be cut from 0.25” thick material (good materials include Corian, Avenite, Translucent
Plexiglass) and the photograph below shows a lithophane cut into Avenite.
We estimate that this tutorial should take you approximately 15 minutes to complete.
Figure 1. The finished Lithophane
Calculating the toolpaths for a Lithophane is very quick and easy and requires 6 key stages.
1. Open an image file
2. Specify the required size
3. Calculate the 3D Roughing toolpath
4. Save the Toolpath
5. Calculate the 3D Finishing toolpath
6. Save the Toolpath
4
1.
Opening Image
1.
Click the Load Image icon.
2.
Select the file required and click the Open button
PhotoVCarve will open photographs that have been saved in the following formats.
JPG, BMP, TIF, PNG, GIF
The photograph selected will now be displayed in the 2D window
5
2.
Set the Material Size
Click on the Set Image Size and complete the form as shown below
7. Enter the Height of the job and the Width will automatically be completed.
8. Enter the Material Thickness = 0.25” for this example
Specify the Job size, XY & Z origins and Material thickness
Click the Apply button to move onto Step 3.
6
3.
Calculate a Roughing Toolpath
Click Set Cutting Parameters and complete the form as shown below.
9. In this example we are using
1/8” diameter Ball nose cutter to rough machine the design.
Carving Max Depth should be around 0.1”
Line spacing of 50% as this is only roughing
Cutting at 45 degrees reduces the load on the cutter for the first pass
Always check the Invert Light / Dark option for Lithophanes
Rapid clearance gap of 0.25”
Notes
A Roughing Toolpath is only required if the material being used is thicker than
0.125” / 3mm. If the material is thicker than 0.25” / 6mm, the Roughing pass
needs to be run on the machine at multiple Z levels to clear the excess material.
7
4.
Save the Toolpath
9.
The Estimated machining time is shown on the form
10.
Select the Postprocessor for your CNC machine from the pull-down list.
11.
Click the Save Toolpath button and give the Roughing toolpath a suitable file name.
12.
The complete Lithophane design can be saved as a .PVC format.
Running the Toolpath
The Roughing toolpath is used to remove the excess material from the material and the Z0 origin needs to be
setup 0.080” / 2mm into the material as shown in the diagram below.
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5.
Calculate a Finishing Toolpath
Return to Step 3 and Click Set Cutting Parameters and complete the form as show.
13. In this example we are using
0.04” diameter Ball nose cutter to finish machine the design.
Carving Max Depth should be around 0.1”
Line spacing of 15% to produce a good finish
Cutting at 45 degrees reduces the load on the cutter for the first pass
Always check the Invert Light / Dark option for Lithophanes
Rapid clearance gap of 0.25”
Note
Conical Engraving cutters with a ball nose tip radius are excellent for this type of work as
the tapered cutting angle is stronger than conventional parallel ball nose cutters
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6.
Save the Toolpath
15.
The Estimated machining time is shown on the form
16.
Select the Postprocessor for your CNC machine from the pull-down list.
17.
Click the Save Toolpath button and give the Finishing toolpath a suitable file name.
18.
The complete Lithophane design can be saved as a .PVC format.
Running the Toolpath
The Z0 origin for the Finishing toolpath needs to be setup 0.100” / 2.5mm into the material as shown in the
diagram below.
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