Sam Buchanan's Strip Canoe Project
Sam's Construction Log, page four
Fiberglassing Begins
8/30/00; After a summer of no canoe building, it is finally time to get back to work on the project. The hull was sanded three times with an orbital sander using 40-grit paper, and minor imperfections were filled with a mixture of glue and sanding dust. The next step is to apply a sealer coat which will prep the wood for the fiberglassing operation.
The epoxy products we are using come from Raka Inc. This is an industrial epoxy that is repackaged by Larry Raka at a very attractive price. He has several formulations available, but the 350 hardener and 127 resin is recommended for projects such as ours. Raka has a very informative web site with an on-line users manual for his products.
The 350 and 127 are mixed 1:2 by volume. The easiest way to get the proper mix is with pumps which are calibrated to deliver the correct proportions. The resin pump yields twice the volume with one stroke as the hardener pump. We purchased some plastic mixing pots from Raka that are also graduated.
I picked up some disposable paint tray liners at Sherwin Williams. The foam roller covers are from Raka, and the latex gloves are from Wal-Mart.
The epoxy is rolled in a light coat over the hull. This goes very quickly since basically we are just "painting" the canoe with epoxy. For the first time we can really see the wonderful color of the cedar come to life!
Only 22 strokes of the epoxy pumps (probably less than a quart) was needed to cover the hull. After the epoxy has cured for twenty-four hours, it will be sanded once with 100-grit paper and will be ready for the first fiberglassing operation. The sealer coat is necessary so the wood won't absorb the resin during the glassing process. This would "starve" the cloth and prevent proper bonding of the cloth to the wood.
9/2/00
This evening I applied fiberglass cloth reinforcements to the stem areas. This area of the canoe takes a pounding during use and also needs strengthening because strip canoes have no internal stem.
A couple of strips of cloth are applied as shown. A foam brush works well for transferring the resin to the cloth and smoothing out most of the wrinkles. A few strategically located slits in the cloth assist with getting the cloth to follow the stem profile. A plastic squeegee was used to pick up excess resin after everything was in place.
You have to work pretty fast if the resin remains in the mixing pot. The curing process generates a lot of heat which accelerates the catalytic action of the hardener. A better method would be to transfer the resin to a shallow tray.
A sanding session will remove lumps and bumps in the edges of the cloth and then we will be ready for glassing the entire hull.
Forward to Sam's construction log, page five