Hello...
Last weekend I epoxied the hull of my Freedom 17. First canoe - first time ever working with epoxy. I thought I had done everything right - read every imaginable article I could find, went through all the topics on the forum etc. Even had Canoecraft open on my workbench through the whole process, and followed it to a tee (exepct I rolled on the third coat).
Had a couple of problems though...First off, when I unrolled the cloth off the roll, there a 'kink' buried in it, so for about ten feet on one side, I had a concurring little ridge to contend with.
Anyways, I had squeegeed everything flat, got out the kinks and finished up with what I thought was a mirror finish.
I was going skiing the next morning, so only had time for a quick check before I went, and was completely dismayed. The kinks raised themselves - so on one side I had ridges - maybe 6 of them along about 10 feet of the canoe (each was about half an inch wide, maybe 8 to 12 inches long.) On the other side, I had a bunch of bubbles - all epoxy filled, but bubbles neverthelss. I can assue you, it's miserable sitting on a chairlift knowing that back home your pride and joy isn't perfect.
So - I've let the epoxy harden, and went at it with an assortment of scrapers. I got the bubbles out. On the ridges (which are about a foot long), I've scraped down to the cloth, but not through it. When I sponge it down, I can see I'm going to have some blemishes, but overall, it's going to look really good. I'm going to sand the entire hull now with 120 grit, and brush on a fourth coat. ( I know this'll add some weight, but I recently realized that if I take my 16 year old nephew canoing with me - he can carry it!)
So I've been thinking ahead to 'next time' (as we all know that our first canoe is a practice canoe - right?).
I think next time I'll drape the fiberglass cloth over the canoe, then starting at the middle station, I'll stretch it across the canoe snug, then staple the excess to the station mold on both sides. Then - move ahead one station and staple the excess again. Then back two feet - snug it up and staple it. And so forth - working towards the stems - till the cloth is completely snug along the entire length and affixed with staples. I even think this will help with the wet-out coat - the cloth won't be able to shift - and any little kinks are already stretched out.
What do you think about stapling the cloth snug to the canoe prior to wetting it out? Am I missing something?
As always, thanks in advance to your advise, comments and tips...
Bill.
Fiberglass Cloth Idea
I am very aprehensive about glassing my Nomad but I have read that if you have a crease, get rid of it prior to epoxying. Don't know how to do this but was also told to only buy glass on a roll and never let anyone fold it when you buy it. IMHO A bunch of others will chime in on this one...
Joe "Woodchuck" Gledhill
Garden City, MI
Garden City, MI
- Glen Smith
- Posts: 3719
- Joined: Sat May 08, 2004 9:08 am
- Location: Baie-St-Paul, Quebec, Canada
My first word of advice would be to specify that you want the cloth rolled when you order it. Upon arrival, it is a good idea to inspect the cloth to see if it has been rolled without any creases. I realize this isn't always possible since it would mean unrolling it all and rolling it back up again without causing any creases yourself. If the cloth has any problem areas, I would call the supplier and discuss the possibility of having the roll replaced.
Secondly, when you apply epoxy to fiberglass cloth you should time it so that you can stay around and "babysit" it so you can attempt to correct any problems that might occur. Glassing and leaving it alone for several hours is not a good thing to do.
Thirdly, as for stapling the glass to the forms I would be cautious. Most epoxies shrink a bit as they set. Would this cause any unexpected problems? I don't know since I have never tried it. Again, if you can apply the epoxy then check on it at least every 15 minutes for the first 2 hours, you should be able to correct any evident problems. Perhaps you could pull out the staples as the epoxy begins to set.
Secondly, when you apply epoxy to fiberglass cloth you should time it so that you can stay around and "babysit" it so you can attempt to correct any problems that might occur. Glassing and leaving it alone for several hours is not a good thing to do.
Thirdly, as for stapling the glass to the forms I would be cautious. Most epoxies shrink a bit as they set. Would this cause any unexpected problems? I don't know since I have never tried it. Again, if you can apply the epoxy then check on it at least every 15 minutes for the first 2 hours, you should be able to correct any evident problems. Perhaps you could pull out the staples as the epoxy begins to set.
If you can at least hang around long enough for the epoxy to get pretty tacky and then lay a piece of waxed paper large enough to go well past the extent of the ridge and squeegee it gently, the tackiness of the surrounding area might, maybe, help it lay flat until it cures. If the area is horizontal enough to lay some weight over the waxed paper ( e.g. sheet lead or a very thin sandbag) so much the better. Sort of like site selective vacuum bagging. The finish will be different there, reflecting the smoothness of the paper. But after filling the weave by re-coating I don't think it would matter.
My guess is that it could be rather difficult to get the cloth stretched out as smoothly as it can be when it hangs loose. The staples would be likely to cause their own little ridges where they pull, and to fray the weave near them. This is not to say it won't work, but that it's likely harder to do than it sounds. That's why the advice above -- to be vigilant and stick around smoothing as the epoxy cures, is probably very good advice.
To minimize creases, buying uncreased cloth is best, but if it is creased, what can you do? You can drape the cloth, and let it hang for a day or two. You can work the crease out by pulling on the bias, that is diagonally to the weave, in one direction, and then along the other diagonal. The cloth will distort quite a bit as you do this, and going back and forth can let the glass fibers relax back to their uncreased state. This works with all sorts of pulls and unevenness in the cloth. It's probably best to try it first on a scrap: poke it and pull some threads out of line, or fold and rub it to really get it messed up. Then try pulling it alternately along opposite diagonals, and watch it fall into place. But don't pull the threads out.
To minimize creases, buying uncreased cloth is best, but if it is creased, what can you do? You can drape the cloth, and let it hang for a day or two. You can work the crease out by pulling on the bias, that is diagonally to the weave, in one direction, and then along the other diagonal. The cloth will distort quite a bit as you do this, and going back and forth can let the glass fibers relax back to their uncreased state. This works with all sorts of pulls and unevenness in the cloth. It's probably best to try it first on a scrap: poke it and pull some threads out of line, or fold and rub it to really get it messed up. Then try pulling it alternately along opposite diagonals, and watch it fall into place. But don't pull the threads out.
Alan
Hi Bill,
I'm working on finishing my prospector and I've got to say that wrinkled fiberglass was a problem for me as well. I bought my glass on a roll and when I laid it out I had a raised crease. I thought I could iron it out, didn't work. Tried using a hot air gun, didn't work. I finally thought that I would babysit it and keep pushing it down, that just didn't work. At first it removed to much of the epoxy, then when it got tacky the cloth stuck to my scraper. So from my expericence I would say that flaws like you described are doomed from the start. Next time I woun't even start with a flaw, I'll cut it and overlay or just not use the piece. I added a 4 oz layer to the football on the outside which covered my flaws but if you look close enough you can still see where I had problems. I'm hoping that a half dozen coats of varnish will help cover the last of the problems.
Mack
I'm working on finishing my prospector and I've got to say that wrinkled fiberglass was a problem for me as well. I bought my glass on a roll and when I laid it out I had a raised crease. I thought I could iron it out, didn't work. Tried using a hot air gun, didn't work. I finally thought that I would babysit it and keep pushing it down, that just didn't work. At first it removed to much of the epoxy, then when it got tacky the cloth stuck to my scraper. So from my expericence I would say that flaws like you described are doomed from the start. Next time I woun't even start with a flaw, I'll cut it and overlay or just not use the piece. I added a 4 oz layer to the football on the outside which covered my flaws but if you look close enough you can still see where I had problems. I'm hoping that a half dozen coats of varnish will help cover the last of the problems.
Mack
- Glen Smith
- Posts: 3719
- Joined: Sat May 08, 2004 9:08 am
- Location: Baie-St-Paul, Quebec, Canada
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- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
I have done just that in the past Glen, however, the wrinkles I had were folds, and not necessarily creases. I hung the fabric over the hull for two days, in warmer weather, I'm sure.. Depending on how severe the wrinkles/creases are it would probably work.
I'm not too experienced with this issue, but would a little heat, applied to the creased area, relax the fabric?
Rehd
I'm not too experienced with this issue, but would a little heat, applied to the creased area, relax the fabric?
Rehd
Hi Everyone...
Thanks for all the advice and tips. I wish I had asked the question before the cloth was on the boat!
The good news is that I went after the ridges with variety of scrapers, followed up with 400 and 600 grit sandpaper, and the end result is that I've gotten rid of virtually all evidence of the creases. (Unless you look really, really closely). I've sanded the rest of the hull with 120 grit, and I'm all set to brush on a final coat tomorrow morning.
I'll let you know the final result.
Bill
Thanks for all the advice and tips. I wish I had asked the question before the cloth was on the boat!
The good news is that I went after the ridges with variety of scrapers, followed up with 400 and 600 grit sandpaper, and the end result is that I've gotten rid of virtually all evidence of the creases. (Unless you look really, really closely). I've sanded the rest of the hull with 120 grit, and I'm all set to brush on a final coat tomorrow morning.
I'll let you know the final result.
Bill