1982 Hydrostream Viking Restoration

Transcription

1 1982 Hydrostream Viking Restoration Part 2a: The Rebuild Daniel W. Rickey Winnipeg, Manitoba Canada 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. 1

2 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. 2

3 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. 3

4 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. 4

5 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 " [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. 5

6 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. 6

7 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. 7

8 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. 8

9 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. 9

10 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. I found that the new balsa core is a bit wider than the original material and had to be trimmed. This was fairly easy to do using a razor knife. Before installing the new balsa I epoxied a layer of 6 ounce 6" wide tape down the pad. This helped to seal and smooth pad. 10

11 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! 11