August 10, 2012
by Mike Elliott, Kettle River Canoes
One of my current canoe restoration projects is a 16’ Model 44 Peterborough Cedar Strip canoe dating from before 1920.
The hull is in great shape except for a few areas where a plank has cupped. I wanted to bring those strips back tight to the Rock Elm ribs. This is how I did it.
Once all of the old varnish was stripped from the hull (both inside and out), the first step was to soften the wood a little by pouring boiling water over the affected areas (both inside and out).
These canoes are held together with about 5,000 15-gauge copper canoe nails (7/8” or 22 mm long).
The original builders did not use pilot holes for the copper nails, but I took the precaution of drilling a 1/16” (1.6 mm) pilot hole first for each nail. I tried my best to line up with the original nails to get as close to the centre of the 5/8” (16 mm) half-round ribs as possible.
To attach the ship-lapped planking strips to the ribs, the original builders used a solid wood mould and drove the nails straight through the plank and rib into the wood.
To simulate the solid wood mould and provide some backing while driving the nail, I used a small block of wood to receive the nail.
Once the nail was driven fully into the canoe hull from the outside, the wood block was removed to expose the point of the new nail. Originally, once all 5,000 copper nails were driven into the hull, the canoe was removed from the mould. It looked like an inside-out porcupine.
At this point the builder used a cast-steel “dubbing iron” to turn each nail along the rib and hammer it flush to the rib. I used my wood-canvas canoe “clinching iron” to do the same job. I set the iron against the side of the nail and pressed either towards the keelson or the rib-top as I tapped gently on the nail head with my cobbler’s hammer (A side-note here: the cobbler’s hammer has a wide head with a concave face. You can hit the soft cedar as hard as you like without marking the wood).
Once the copper nail was bent over, I placed the clinching iron on top of the exposed nail and hit hard with the hammer to drive the nail flush into the rib.
When completed along the full length of the cupped cedar strip, the plank is sitting nicely against the ribs again. Mission accomplished.