NickD
Recreational Sander
So… Just completed my second restoration: a 1919 16’ OT OTCA (made an appearance at this year’s Assembly) and had an issue with the canvas that comes and goes. Here’s what happened including facts that are either pertinent or potentially interesting:
· Canvas was stretched on the hull in April, I canvas with the canoe right side up, hammock style. I tensioned the canvas without canoe to make sure everything was even then relaxed the canvas, added canoe and re-tensioned. Temperature about 60 or so.
· Tacked canvas starting from midship moving to each end, one side at a time, leaving the ends open where tacking became difficult.
· Removed tension, flipped canoe and hand stretched (using canvas pliers) canvas at each end, tacking and keeping as tight as I could get it. Kept high tension on the extreme ends (mid stem) and worked the stem starting from the bottom around to the top. NOTE: I do all my work solo other than putting the canoe in the canvas initially. Also NOTE: Had an issue with the canvas rippling transversally near the bow and stern on the hull due to what I thought was “pull back” from the ends. I had to work the stretched canvas considerably (I thought) to get it smooth. This involved untacking portions, re-stretching and re-tacking. Also ANOTHER NOTE: Ends tacked and completed 2 days after the rest of the canoe was canvased and tacked, ie. total canvasing occurred over three days.
· At this point canvas is complete, smooth, ends sealed with bedding compound and tacked. I filled the canvas with OT filler and let sit for 5 weeks until it was cured. NOTE: Had the text book ripple of canvas above each tack along most of the hull. At the ends, the ripple was biased to the nearest stem side of the tack.
· Painted the hull. I sanded the filler lightly and put multiple coats of paint to get to the finish I was looking for. Paint: Interlux Dark Blue.
· The morning after the final coat, I decided to move the canoe out of the garage for a little while to “air out”. That day turned out to the hottest and sunniest day of the year. About 3 hours later I returned finding the canvas/filler/paint rippled on the hull on the bottom and side facing the sun. The ripples ran transversally across the hull. Hull was very hot to the touch.
· After a “stern” conversation with myself I expedited the canoe back to the cover of the garage and covered it with cold wet towels to cool it down. Ripples receded somewhat but not completely.
· Over the next five days (in humid weather) the canvas gradually (miraculously) flattened out.
· The canvas behaved at Assembly. And paddled quite nicely too.
· Now, back in the garage, one side at one end has re-rippled mildly. Canoe hasn’t seen water since Assembly.
Did I do something wrong or is there something I should have done better? How tight is tight then canvassing? My first restoration went very well and I’m worried I was a bit sophomoric on the second go-around. If I let the paint cure longer, protected in the garage, would that have prevented the rippling which I assume was caused by the expansion of the dark, heated, not completely cured, painted surface? I'm thinking that if the canoe gets wet again or it gets really humid, it may flatten again.
On another note, the day before we left for the Assembly, my wife made an impressive canoe bag/cover out of white bed sheets that survived the trip up to Assembly and back in glaring sun in an effort to prevent re-occurrence. It worked really well.
· Canvas was stretched on the hull in April, I canvas with the canoe right side up, hammock style. I tensioned the canvas without canoe to make sure everything was even then relaxed the canvas, added canoe and re-tensioned. Temperature about 60 or so.
· Tacked canvas starting from midship moving to each end, one side at a time, leaving the ends open where tacking became difficult.
· Removed tension, flipped canoe and hand stretched (using canvas pliers) canvas at each end, tacking and keeping as tight as I could get it. Kept high tension on the extreme ends (mid stem) and worked the stem starting from the bottom around to the top. NOTE: I do all my work solo other than putting the canoe in the canvas initially. Also NOTE: Had an issue with the canvas rippling transversally near the bow and stern on the hull due to what I thought was “pull back” from the ends. I had to work the stretched canvas considerably (I thought) to get it smooth. This involved untacking portions, re-stretching and re-tacking. Also ANOTHER NOTE: Ends tacked and completed 2 days after the rest of the canoe was canvased and tacked, ie. total canvasing occurred over three days.
· At this point canvas is complete, smooth, ends sealed with bedding compound and tacked. I filled the canvas with OT filler and let sit for 5 weeks until it was cured. NOTE: Had the text book ripple of canvas above each tack along most of the hull. At the ends, the ripple was biased to the nearest stem side of the tack.
· Painted the hull. I sanded the filler lightly and put multiple coats of paint to get to the finish I was looking for. Paint: Interlux Dark Blue.
· The morning after the final coat, I decided to move the canoe out of the garage for a little while to “air out”. That day turned out to the hottest and sunniest day of the year. About 3 hours later I returned finding the canvas/filler/paint rippled on the hull on the bottom and side facing the sun. The ripples ran transversally across the hull. Hull was very hot to the touch.
· After a “stern” conversation with myself I expedited the canoe back to the cover of the garage and covered it with cold wet towels to cool it down. Ripples receded somewhat but not completely.
· Over the next five days (in humid weather) the canvas gradually (miraculously) flattened out.
· The canvas behaved at Assembly. And paddled quite nicely too.
· Now, back in the garage, one side at one end has re-rippled mildly. Canoe hasn’t seen water since Assembly.
Did I do something wrong or is there something I should have done better? How tight is tight then canvassing? My first restoration went very well and I’m worried I was a bit sophomoric on the second go-around. If I let the paint cure longer, protected in the garage, would that have prevented the rippling which I assume was caused by the expansion of the dark, heated, not completely cured, painted surface? I'm thinking that if the canoe gets wet again or it gets really humid, it may flatten again.
On another note, the day before we left for the Assembly, my wife made an impressive canoe bag/cover out of white bed sheets that survived the trip up to Assembly and back in glaring sun in an effort to prevent re-occurrence. It worked really well.