After fitting the inwales and outwales I took the time to give the canoe hull an initial rub down. I concentrated on where I had filled the wire holes and on any marks left by the wires on the corners of the planks – being careful to preserve the lines of the “step”. One exception was that I knocked down the sharp corner between planks numbered one and two on the inside of the hull as this joint was going to be bridged by the fibreglass cloth re-enforcing for the bottom of the hull.
Reading my building bible had made me apprehensive about the process of glassing the bottom of the hull. The suggested technique was to pour on a quantity of epoxy resin and then to brush that out – adding resin where the cloth was not properly wetted but removing resin where the cloth was floating. It all sounded rather hectic and off-putting with inevitable variations in “pot life” making things just that bit more exciting. By ignoring the book and following some good alternate advice the reality was very different. Unhurried and straightforward, with the inside of the hull only slightly more awkward than the exterior.
Glassing the hull:
Let me describe the process, starting with the exterior where only the number one planks need the application of glass cloth. First, I applied masking tape to the edge of the number two planks. I found the best tape for this purpose was a plastic based one intended (I think) for use when painting windows) although a paper based tape would be fine and was what I used elsewhere.
I had taken my roll of glass cloth into the house and taken advantage of a wooden floored corridor to cut the roll into two strips - one a little wider than the width of the two number one planks at their widest. The other strip I was confident would be wide enough to bridge the bottom on the inside. I laid the narrower strip along the hull and trimmed it so that the edges protruded a little beyond the masking tape protecting the edges of the number two planks. Material from the ends of the strip was going to be used later to cover the plank ends where they meet at the bow and stern.
My only other preparation was to trim a cheapish paintbrush so that the hairs were only 15mm or so long – giving me a mildly stiff brush which would not pick up too much resin. If you follow on and do things as I did them, then it is worth preparing three such brushes – sizes are not important but I found those with a 5cm width to work very well. If you clean the brushes after use then they can be used again later in the build process.
I mixed a small batch of epoxy resin (four pumps) in a pot and then, starting in the middle of the canoe at the centre line, I began to wet out the glass cloth using my modified paintbrush. Work enough resin into the cloth to make it transparent but not enough for the resin to build up on top of the cloth. The idea is to wet the cloth thoroughly but to leave a slightly matt finish – certainly not glossy. Continue working towards the outside edge of the planks and towards both the bow and stern. When you run out of epoxy – just mix another batch in the same pot and keep working. You can adjust the mix quantity towards the end. By mixing small batches you can take your time, working steadily towards the finish.
All you have to do now is clean your brush (if you have the relevant solvent) and wait for the epoxy to start to go off. This is also a good moment to cut two strips of glass cloth from the spare ends “on the bias” to cover the stem and stern. The strips should be cut at 45 degrees to the weave of the cloth as this will maximise the number of threads crossing the plank joints while also being easy to stretch around the curves.
Depending upon the ambient temperature your wait might be just a few minutes or even a couple of hours. When things feel right, load a Stanley Knife with a fresh blade and use this to cut through the resin and glass at the edge of the number one plank – peeling the excess glass cloth away with the masking tape. The way the planks are set makes this particularly easy on the outside of the hull.
Mix another small batch of un-thickened epoxy and paint a thin layer onto the planks at the stem and stern where your bias cut strips of cloth will be located. (This was why you needed the second prepared brush.) This will help hold the cloth into place while you wet it out and stretch it to shape. Lay the cloth pieces over the epoxy and then wet them out. Then I found it simplest to manage the final shaping and smoothing using my gloved hands.
I also decided to double up the glass on the keel by adding a length of woven glass tape down the centre line of the hull. I cut the tape to length and then stuck it in place – taking advantage of the fact that the epoxy from the initial layer of glass cloth was still just tacky. I then took up my third prepared brush and wetted out the glass tape, working from the middle of the boat and using small batches of epoxy just as before.
Thus I was able to re-enforce the bottom of the canoe in a single, rather pleasant working session – although I did manage to get through five pairs of protective gloves.
Reading my building bible had made me apprehensive about the process of glassing the bottom of the hull. The suggested technique was to pour on a quantity of epoxy resin and then to brush that out – adding resin where the cloth was not properly wetted but removing resin where the cloth was floating. It all sounded rather hectic and off-putting with inevitable variations in “pot life” making things just that bit more exciting. By ignoring the book and following some good alternate advice the reality was very different. Unhurried and straightforward, with the inside of the hull only slightly more awkward than the exterior.
Glassing the hull:
Let me describe the process, starting with the exterior where only the number one planks need the application of glass cloth. First, I applied masking tape to the edge of the number two planks. I found the best tape for this purpose was a plastic based one intended (I think) for use when painting windows) although a paper based tape would be fine and was what I used elsewhere.
I had taken my roll of glass cloth into the house and taken advantage of a wooden floored corridor to cut the roll into two strips - one a little wider than the width of the two number one planks at their widest. The other strip I was confident would be wide enough to bridge the bottom on the inside. I laid the narrower strip along the hull and trimmed it so that the edges protruded a little beyond the masking tape protecting the edges of the number two planks. Material from the ends of the strip was going to be used later to cover the plank ends where they meet at the bow and stern.
My only other preparation was to trim a cheapish paintbrush so that the hairs were only 15mm or so long – giving me a mildly stiff brush which would not pick up too much resin. If you follow on and do things as I did them, then it is worth preparing three such brushes – sizes are not important but I found those with a 5cm width to work very well. If you clean the brushes after use then they can be used again later in the build process.
I mixed a small batch of epoxy resin (four pumps) in a pot and then, starting in the middle of the canoe at the centre line, I began to wet out the glass cloth using my modified paintbrush. Work enough resin into the cloth to make it transparent but not enough for the resin to build up on top of the cloth. The idea is to wet the cloth thoroughly but to leave a slightly matt finish – certainly not glossy. Continue working towards the outside edge of the planks and towards both the bow and stern. When you run out of epoxy – just mix another batch in the same pot and keep working. You can adjust the mix quantity towards the end. By mixing small batches you can take your time, working steadily towards the finish.
All you have to do now is clean your brush (if you have the relevant solvent) and wait for the epoxy to start to go off. This is also a good moment to cut two strips of glass cloth from the spare ends “on the bias” to cover the stem and stern. The strips should be cut at 45 degrees to the weave of the cloth as this will maximise the number of threads crossing the plank joints while also being easy to stretch around the curves.
Depending upon the ambient temperature your wait might be just a few minutes or even a couple of hours. When things feel right, load a Stanley Knife with a fresh blade and use this to cut through the resin and glass at the edge of the number one plank – peeling the excess glass cloth away with the masking tape. The way the planks are set makes this particularly easy on the outside of the hull.
Mix another small batch of un-thickened epoxy and paint a thin layer onto the planks at the stem and stern where your bias cut strips of cloth will be located. (This was why you needed the second prepared brush.) This will help hold the cloth into place while you wet it out and stretch it to shape. Lay the cloth pieces over the epoxy and then wet them out. Then I found it simplest to manage the final shaping and smoothing using my gloved hands.
I also decided to double up the glass on the keel by adding a length of woven glass tape down the centre line of the hull. I cut the tape to length and then stuck it in place – taking advantage of the fact that the epoxy from the initial layer of glass cloth was still just tacky. I then took up my third prepared brush and wetted out the glass tape, working from the middle of the boat and using small batches of epoxy just as before.
Thus I was able to re-enforce the bottom of the canoe in a single, rather pleasant working session – although I did manage to get through five pairs of protective gloves.
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