My First Wood Canvas Canoe build Part 3
The stem to gunwale joints can be made in a variety of ways but it is usually some form of open tenon or bridle joint. Even so to many people it doesn’t resemble a mortice and tenon very much and I have to agree its not much like those used in furniture making.
First a tenon is cut on the top of the stem.The stem can be trimmed down a little to make this easier but it is still a little tricky with the stem moving around. I carefully cut the shoulders of the joint with my Japanese pullsaw before paring down each side with a chisel taking care to watch the grain in case it decided to run into the tenon itself. If it does start doing that I stop and work across the face of the joint from each side trying to slide the chisel in the opposite direction away from the shoulder to avoid it tearing.
The decks will sit over the end of the tenon so the tenon is then cut short to about half the thickness of the deck.
I made my decks in my usual way that you will see in my other bloggs so I won’t go into too much detail just to say they are joined with a biscuit jointer and I use a wooden moulding plane and scrapers to make the underside concave. Here is a sequence of pictures showing the process.
The decks are trial fitted with screws so I can check the gunwales and everything are in the right place using a string line and level and checking sight lines.
The ends of the gunwales were also trimmed to length so they fit neatly against each other enclosing the tenon. I took the decks off again and shaped the inside edges before sanding them.
The gunwales are given a slight taper where they run to the decks using a block plane
Next comes tacking the ends of the planks to the stems and this is best accomplished with the canoe upside down. I also discovered that I would need shorter tacks for this than I had in stock so as there aren’t many of them I decided to trim down some of my longer ones with pliers. They are ring shank nails and I am pre drilling them into the stems so the points are not really needed. This meant I spent 20 mins or so cutting some down with pliers. Tedious but quicker than going online placing an order and waiting for it to arrive! I made myself a simple jig to sett he cutting length eliminating guesswork.
With one set of end planks fitted you can clearly see the problem my planking layout created that I mentioned earlier and now we come to what many may see as a controversial solution!
These canoes are usually built without the use of glue but I have already used some polyurethane glue to glue up my deck laminates so I see no reason why I can’t glue in some cheater planks to fill my gaps. I will of course allow an expansion gap between the planks for when they eventually get wet during use as this is recommended in many writings about this kind of canoe and I am increasing the plank width so this may cause more movement. Polyurethane glue is a relatively new invention so wasn’t around when these canoes were invented just like routers were not available in Chippendale’s time, but I bet he would have used one if he had it!
I carefully shaped each triangle of planking to fit then clamped them in place using as much ingenuity as I could muster often including delicately balanced quick cramps and tiny wedges like this.
The glue I used was quick setting only taking around 5 minutes for an initial cure so I was able to alternate ends as I worked and keep going till they were all done. I could also clean off excess glue relatively easily before it became too hard.
All of a sudden it is starting to look so much more like a canoe instead of a loose collection of planks and ribs!
Thats all until next time when I will fit the cant ribs.