Over the last few weeks, as well as completing epoxy on the interior, I have erected a 'spray booth' in the carport out of canvas and plastic sheets. Today I sprayed the final of 4 coats of heavy duty Polurethane clear coating. This is essential for UV protection. I opted for a single part coating as this will be an area with high traffic, so re-coating by hand may be required in the future. The overall effect of the ' natural' timber finish is very pleasing, although certainly not 'dining table' quality. I am not sure I would do a clear finish again on a canoe if I could get away with it, but I have learnt a lot from the exercise. I suspect that a painted finish might be a lot harder to make look as attractive on the interior, as the interior surface is nowhere as easy to make 'bump free' as the outside of the hull. Next - spray painting the outside of the hull!
Bum Protection 01 February 2008
The real world approaches - dragging the canoe over stones and grass, so time for some protection. The two rubbing strips are made out of Jarrah - a tough wood like Mahogany. I planed them to about 8 mm thick. They mostly run along the flat part of the hull, but they bend up slightly at both ends. Fastening them to the hull wasnt easy. The plans recommend a matching strip of wood on the inside as well. What I did was epoxy the strips to the hull using brass screws to help hold them down. However, the thin hull didnt provide much grip for the 12 mm screws, which had to be short so they didnt go right through the hull. In the end I had to use straps to hold the ends close to the hull while the epoxy hardened. Future Note - there is a lot be said about not making the rubbing strips an integral part of the hull, as they get knocked about, banged and broken. Especially (December 2009 in Tasmania) when a 80 kmh gust picks the boat up off its stand and blows the whole canoe 50 metres down a hill. Rather than ruin a holiday, a tube of quick seting epoxy to stop water getting into the little screw holes, , a can of auto touchup paint, and all is well until full repairs can be made. If the strips had been held down with more substantial fastenings, maybe major damage would have occurred to the hull.
More Undercoats - 02 February 2008
More filling with car filler, then spraying another layer of undercoat. Even more filling with Epoxy mixed with microballoons to get even the smallest imperfections under control. The finish needs to be 'perfect' because of the small amount of expensive two part final coat I bought. When spraying, a lot of the paint goes into the atmosphere, so a lot of effort goes into being economical. The cost of the finishing paint - 2 X 1 litre ($100 per litre) for 2 part undercoat/sealer with thinners, 1 litre of two part finish paint with thinners $130. Add up epoxy and body filler, sandpaper , spray mask filters, Acetone for cleaning the spray gun etc the finishing coats cost more than the wood for the entire canoe ! Approx $400