Traveler

Yup - agree that flexibility is critical to SOF performance and durability, but a couple of thin coats of epoxy over the skin doesn’t seem like it will change that very much. Have you ever taken a single piece of cloth - polyester or nylon or even fiberglass - and wet it out with epoxy on its own (ie not bonded to anything)? Once dry It is stiffer than uncoated cloth, but still waterproof and very flexible - you can bend it, fold it over on itself, even tie a strip of it into a knot. So with a couple of thin coats I am not worried about brittle in the sense of shattering on impact. Epoxy is less flexible than the cloth though (as is paint or polyurethane), so a question I have is whether the bond might work loose over time since it probably won’t penetrate the fabric as well as some coatings. I have looked high and low for any information on use of epoxy coatings on SOF, and can’t really find anything here or elsewhere on long-term, “real life” experience, aside from some older posts on other forums from a few people who have done it and claimed it works fine, and others who warn that the world will end if you try it. But it’s pretty clear that there are very few hard and fast “rules” for SOF builds (life would be so much easier if there were), as is evidenced by the wide variety of coatings that people swear by, all for very good reasons. So I’ll probably invest $50-$75 worth of epoxy and cloth in an experiment on this. I’ll at least satisfy my own curiosity, but I suspect it will actually work out ok. If it does work I’ll post my impressions here if there is any interest - if it is a miserable failure you will probably never hear from me again ?.

I should also say that I am talking about just epoxy as a coating, not fiberglass cloth as well.

Thanks Jeff - I guess the “why” is mainly because I have a lot of epoxy on hand and I am familiar with how to apply it. It is more expensive than paint, but not that bad and quite a bit cheaper than something like Corey’s Goop (which after my last kayak I have decided I won’t use anymore - just too hard for me at least to get a decent-looking application and you can’t go back and touch things up once it dries). As to weight, it probably would be a bit heavier, but not that much if you just do the hull and paint the deck - probably one quart would cover the bottom of the boat below the gunnels with 3 coats, so around 2 pounds or so for my 15 footer - that plus a light coat of paint or varnish for UV protection can’t be much more than the weight of 4-6 coats of paint. And likely not more than a full application of Corey’s Goop, which I have measured at 3 pounds total for a kayak my size. Anyway, I agree with your points, but willing to live with a small weight penalty (and since I already have the epoxy on hand there really isn’t a cost issue). My main concern with trying it is whether it would stick well to the cloth over time.

Anyone have experience with epoxy as a coating for 9 ounce polyester? Have read posts elsewhere (from 5 or 10 years ago) where people have apparently used it successfully over very lightweight Dacron polyester cloth, including with a layer of fiberglass cloth, but it doesn’t seem like a very common practice which makes me hesitate. But I have done some small samples and it seems very promising - has anyone here given this a try in the past? If so, how did it work out? Thanks Tony

Thanks all for this good advice. This is my first SOF, but I have built a stripper canoe where I quickly realized that there is no single thing that will get you light weight - gotta look for ounces wherever you can find them to save pounds overall. Hence my question. But I like andy000's point that once you reach a manageable weight there is no real reason to keep looking for more reductions. With my frame now at about 21-22 pounds excluding coaming, I think I can keep the whole thing to under 35 pounds after skinning, which will be fine by me. Thanks again

About to start skinning a 16 foot fuselage frame, touring style kayak, primarily for light duty overnight tripping. Trying a few things to keep the weight down while ensuring respectable durability, and was thinking that I might shave a couple of pounds off by using a heavier fabric only on the bottom up to the gunnel (e.g. 9 ounce poly or 12 ounce nylon), and a light fabric (3 ounce Dacron) for the deck, where presumably there wouldn't be much stress/abrasion risk. Would staple both top and bottom halves along the gunnel and cover with a lightweight rub strip. Anyone done this? Any reason why it would be a bad idea from a structural (or other) point of view? Thanks all