by Mike Elliott, Kettle River Canoes
email: artisan@canoeshop.ca
During the restoration of a wood-canvas canoe, it is rare to have to replace the entire stem in the canoe. However, when faced with the restoration of a canoe which is more than 100 years old, a new stem (or two) is more than likely going to be part of the project.
I restored a J. H. Rushton Indian Girl canoe (c. 1905). Both stems had extensive rot and one was broken in two places. Rushton made his stems from a solid piece of rock elm. Since this wood is nearly extinct now (thanks to Dutch Elm Disease), I used straight-grained ash 1″ (25mm) thick (at the lumber yard this is referred to as 4/4 ̶ pronounced four-quarters).
The first step is to remove the stems from the canoe. I use both a tack remover and a Japanese concave cutter bonsai tool to remove the fasteners without doing too much damage to the ribs, planks and stems in the canoe.
The next step is to create a bending form. Here, I present the dimensions of the bending form required for the Rushton Indian Girl.
It is comprised of three layers of 5/8″ (16mm) plywood. I ask my local building supply centre if they have any damaged sheets of plywood. I can get all of the wood I require for a fraction of the cost of full sheets of plywood. All three piece have the same curve but the centre piece of plywood has a longer base which clamps easily into a work-bench vice.
I start by placing the original stem on one piece of plywood and drawing the inside curve of the stem onto it.
I then keep the stem-top in the same location as the original while rotating the stem until the curve is about 3½” (9cm) greater than the original. The form shape is then drawn onto the plywood and is extended about 6″ (15cm) at both ends to accommodate the clamping system.
The form shape is cut with a saber saw or band saw. The first piece is then used as a template for the other two pieces. Once assembled, the form is sanded more or less square with a belt sander or an angle grinder set up with a 24-grit wood grinding disk. The final form is 1.875″ (48mm) wide.
The base-end of the stem is 1.1875″ (30mm) wide and 0.875″ (22mm) thick. I bend a piece of ash which is 1¼” (32mm) wide and 1″ (25mm) thick. This allows me to shape an exact replica of the original.
The clamping system is attached to the bending form with enough space for the new wood and a backing strip. The new stem stock is soaked in water for four days, steamed for 60 minutes and bent onto the form where it remains for at least a week. When removed from the form, the new wood will spring-back slightly and ought to come to the same shape as the original (or close enough).
The original stem is much more than just the curve in its profile. It is tapered at the stem-end, angled to accept planking and notched to accept ribs. Draw the rough dimensions and contours onto the new stem (first with a pencil and then with a permanent ink pen).
Use a Japanese cross-cut saw or a dovetail saw to cut the sides of the rib notches at the correct angles and depths. Use a wood chisel and mallet to remove the bulk of the material in each notch.
Check the dimensions of each notch on the original and use the chisel to shave each new notch to the desired thickness.
Use an angle grinder set up with a 24-grit wood sanding disk to carve the desired angles and tapers into the new stem.
Work slowly and carefully with a random-orbital sander and 60-grit sandpaper (checking dimensions with calipers against the original) until the new stem is an exact replica of the original.
Turn the canoe upside down and use spring clamps to hold the new stem in place while you drill pilot holes for bronze ring nails to attach it to the ribs.
Use a cobblers hammer backed with a clinching iron to drive the ring nails tight.
Turn the canoe right-side up and sight down the center line. Position the stem so it is lined up straight down the center line and clamp it in place. Pre-drill holes for 16mm brass canoe tacks and attach the new stem to the original planks.
Mark the height of the stem-top against the underside of the inwale ends.
Use a Japanese cross-cut saw to trim the stem-top to its desired height. I cut it a little long and use a random-orbital sander to achieve a snug fit.
Attach the rest of the planking to complete the job.
All of this (and much more) is described in my book – This Old Canoe: How To Restore Your Wood Canvas Canoe.
If you live in Canada, CLICK HERE to buy the book.
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