Part IIa: The Rebuild

1982 Hydrostream Viking Restoration
Part 2a: The Rebuild
©Daniel W. Rickey
Winnipeg, Manitoba
Canada
daniel@CancerCare.mb.ca
2000-07-19
Introduction
Part one of this report showed how the shoddy manufacturing necessitates the replacing of all
wood in this Viking. In Part 2a I show the procedures I used to replace the stringers and pad core.
Acknowledgements
I would like to thank Mark Casper for operating the International HydroStream Registry web site. It
is an excellent resource for those who own or are considering the purchase of a HydroStream. I
would like to thank Russ Wernick for his helpful discussions and suggestions during this rebuild.
The Rebuild
For the rebuild the boat was left on its bunk trailer. Because the boat is not perfectly supported I
didn’t want to remove too much of the structural wood from the boat at once. Thus the rebuild is
carried out in steps.
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Figure 1 I initially removed the port stringer. This was very easy to do as the glass
work was minimal (at best!) and the wood was mostly rotted away. The fibreglass
covering the balsa core was also very poorly done and was fairly east to cut out using
an abrasive disc. The balsa was removed using a hammer and chisel. It was slow
work.
Figure 2 Shown is the stern in the region of the
bilge drain tube. Most of the pad core has been
removed except where it goes under the drain
tube.
The pad has a lot of embedding
compound used to hold the balsa down. Even
though this stuff wasn't completely bonded to
the fibreglass and could be scraped off with a
wood chisel it was very slow work. I used a belt
sander on the remaining bits. At this point the
drain tube must be removed. The tube goes
through a block made from 3 1/2”-thick pieces
of plywood: this block must also be removed.
The very end of the port stringer is still in place
and must be cut out. Note that the starboard
stringer has a large area of bare plywood, i.e.
no glass or resin.
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Figure 3 At this point the bilge tube and support block have been removed. The
support block was rotted as well. The end of the port stringer has been removed. The
chisel shows the large hole that allowed the bilge water into the core.
.
Figure 4 This is the same region after it has been cleaned up a bit.
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Figure 5 There is a channel running beside each stringer that allowed bilge water to
completely wet the bottom of the bare stringers. The channel contains a lot of very
dirty (from the bilge water) poorly-wetted chop.
Figure 6 A wire wheel in an electric drill worked well and removed most of the dirty
chop. Sandpaper wrapped around a piece of plywood cleaned-up the rest.
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Figure 7 Once the pad was cleaned up I measured the remaining stringer. It was
about 89.5” long, 5.5” high towards the bow, and 4.5” high at the stern.
89.81"
[228.1cm]
.50"
[1.3cm]
36.00"
[91.4cm]
88.25"
[224.2cm]
Figure 8 I didn't like the design of the original stringers. Far too much material was
cut out for the drain holes. I cut much smaller holes. In addition, I cut holes, not a
semicircle as in the original design. I also made the stringers just a bit longer, i.e., 90"
instead of ~89.5". I did make one mistake cutting out the stringers: they are now only
5” high at the bow end instead of 5.5”. This can be fixed later.
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Figure 9 At this point one stringer is ready to be mounted. Before mounting I finished
cleaning the junk off of the pad as well as the area in the stern where the drain hole
and stringer separator block goes. I also checked to make sure the pad is as flat as
possible otherwise any hook or rocker will be mine. Because I am using an epoxy
resin that develops an amine blush, I only coat as much of the stringer with epoxy as is
required to mount it. Thus I set the stringer in place and used a pencil to trace the
areas to coat.
Figure 10 Here the port stringer has been epoxied in place.
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Figure 11 The starboard stringer was then cut out. This stringer was not completely
rotten and required a bit of prying to to remove. It turns out that there is a fair bit of
variability in the manufacture of the boat (as expected). The stringer I had cut to match
the first one would not fit. I had to cut another and spend a few hours to get it to be a
reasonable fit to the oat. Overall I found that if I could get the bottom of the stringer to
within a 1/16" of the hull that is about as good as it got.
I also found that the wooden yard/meter sticks I was using were all curved: I now use
metal carpenter's levels of various lengths. Because I didn't remove the vertical ledge
between the pad core and stringer for alignment reasons I couldn't see the gap
between the bottom of the stringer and the hull bottom. (Except at a few points where I
trimmed the ledge). To find high points that needed to be sanded I resorted to making
my own crude "Plastiguage". For this I borrowed some PlayDough from my son. I
rolled it into a long snake having a diameter of about 1/8". This was to be placed on
the hull bottom and the stringer push down on top of it: the thinnest PlayDough would
correspond to high points. Because PlayDough contains a small amount of oil, I
placed it in a transparent plastic bag before laying it in the hull.
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Figure 12 The balsa core extends under the front floor. Because the core around the
front of stringer was very poorly fibreglassed the core has rotted here as well. Thus
the front floor must be removed.
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Figure 13 The front floor was easy to cut out. The floor was not coated underneath
and was rotten - of course.
Figure 14 The balsa core is in much better shape from the middle of this floor and up
towards the bow. In addition, the core narrows down considerably forward of this floor.
Thus I will only replace the balsa from the front floor aft.
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Figure 15 Here I have removed enough core to enable me to recore the pad. More
core will be removed later.
Figure 16 The photo shows the balsa cut and ready to epoxy to the pad.
the new balsa core is a bit wider than the original material and had to
This was fairly easy to do using a razor knife. Before installing the
epoxied a layer of 6 ounce 6" wide tape down the pad. This helped
smooth pad.
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I found that
be trimmed.
new balsa I
to seal and
Figure 17 I then coated the bottom of the balsa with a coat of non-thickened epoxy. I
mixed a thick batch of epoxy and filler and coated the pad. I then seated the balsa
core (scrim-side up) into this mixture. To hold the core down, I place a few concrete
block (wrapped in plastic bags) on top of the core.
Figure 18 Once the epoxy holding the balsa in had set up a bit I epoxied another 6"
wide fibreglass tape on top of the core. It should be noted that the stringers have not
been covered yet. When they are, the pad core will have more glass placed on top of
it. Notice how much better the new core looks!
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