Even more canoe stuff
Aug. 18th, 2010 07:01 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
catsittingstillThis morning, I put the fiberglass on.
What this actually means, is that I put the big patch of fiberglass on. Because canoes aren't flat, or really any shape that can be covered with one flat sheet with minimal distortions, fiberglassing is done in stages. In one stage (often done first but not always) you put on a main sheet of fiberglass, which covers the bottom and the sides, and almost all the way to the front and the back. That is what I did this morning.
Now you may recall I had already put the sealer coat of epoxy on the bare wood hull. This went fine and I was pretty happy with it, though it turns out I only put on about half as much as Susan Van Leuwen did in her book where her demonstration canoe was also a Wee Lassie II. I hope I did it right. Then, since my epoxy was curing to a rubbery non-tacky stage in about 1/3 the time as hers, (she was using a different expoy and working at a cooler temperature) I figured I had 1/3 the amount of time when I could get a chemical bond between layers, meaning 2 days, meaning I didn't need to sand, since I was putting the main sheet of fiberglass on 24 hours later.
I sure hope this was true, because it turns out she sands between the sealer coat and the main fiberglassing step, and I didn't. (if your epoxy has cured to the point where you can't get a chemical bond, sanding it creates scratches that the next layer of epoxy fills up, creating a mechanical bond).
It *should* be okay.
The main fiberglass piece took 30 fluid ounces of epoxy, mixed in 5 batches of 6 fluid ounces each (4 of epoxy and 2 of hardener.) I was moving about as fast as I could reasonably go.
Then when the main fiberglass piece had cured to a rubbery tack-free stage, I used a sharp knife to cut the extra fiberglass away from the sheer (the part where the gunwales will go) and put an extra strip of fiberglass all the way down the middle. This was because the bottom of the boat is a comparatively sharp vee, and Susan thought, and I agree, that this may take more abuse than the rest of the hull. I also put another coat of epoxy over the whole boat to help fill up the weave of the big fiberglass piece. This took another 12 fluid ounces of epoxy.
Tomorrow morning I volunteer at the Jefferson Rural Clinic starting at 9 am. I am hoping I can put the little pieces of fiberglass that go on over the stems on in the morning. It will depend on how early I get up and how much fiddling is necessary to prepare the ends (the edges of the other pieces of fiberglass have to be sanded down so they're not lumpy and bumpy under the new layer, and that means the epoxy has to cure properly so that sanding back and forth over it doesn't rip it off the wood. Twelve hours *should* do it. We'll see.
It sure is a pretty boat though.
What this actually means, is that I put the big patch of fiberglass on. Because canoes aren't flat, or really any shape that can be covered with one flat sheet with minimal distortions, fiberglassing is done in stages. In one stage (often done first but not always) you put on a main sheet of fiberglass, which covers the bottom and the sides, and almost all the way to the front and the back. That is what I did this morning.
Now you may recall I had already put the sealer coat of epoxy on the bare wood hull. This went fine and I was pretty happy with it, though it turns out I only put on about half as much as Susan Van Leuwen did in her book where her demonstration canoe was also a Wee Lassie II. I hope I did it right. Then, since my epoxy was curing to a rubbery non-tacky stage in about 1/3 the time as hers, (she was using a different expoy and working at a cooler temperature) I figured I had 1/3 the amount of time when I could get a chemical bond between layers, meaning 2 days, meaning I didn't need to sand, since I was putting the main sheet of fiberglass on 24 hours later.
I sure hope this was true, because it turns out she sands between the sealer coat and the main fiberglassing step, and I didn't. (if your epoxy has cured to the point where you can't get a chemical bond, sanding it creates scratches that the next layer of epoxy fills up, creating a mechanical bond).
It *should* be okay.
The main fiberglass piece took 30 fluid ounces of epoxy, mixed in 5 batches of 6 fluid ounces each (4 of epoxy and 2 of hardener.) I was moving about as fast as I could reasonably go.
Then when the main fiberglass piece had cured to a rubbery tack-free stage, I used a sharp knife to cut the extra fiberglass away from the sheer (the part where the gunwales will go) and put an extra strip of fiberglass all the way down the middle. This was because the bottom of the boat is a comparatively sharp vee, and Susan thought, and I agree, that this may take more abuse than the rest of the hull. I also put another coat of epoxy over the whole boat to help fill up the weave of the big fiberglass piece. This took another 12 fluid ounces of epoxy.
Tomorrow morning I volunteer at the Jefferson Rural Clinic starting at 9 am. I am hoping I can put the little pieces of fiberglass that go on over the stems on in the morning. It will depend on how early I get up and how much fiddling is necessary to prepare the ends (the edges of the other pieces of fiberglass have to be sanded down so they're not lumpy and bumpy under the new layer, and that means the epoxy has to cure properly so that sanding back and forth over it doesn't rip it off the wood. Twelve hours *should* do it. We'll see.
It sure is a pretty boat though.
![[identity profile]](https://www.dreamwidth.org/img/silk/identity/openid.png){kind=small}
no subject
Date: 2010-08-19 12:05 am (UTC)no subject
Date: 2010-08-19 10:41 pm (UTC)