I also use 10 oz cotton duck, but I now use only the domestic cloth. I have tried the foreign cloth twice and had weave problems both times. I have never measured it on a kayak, but I know when I did canoes I stretched it a lot more. I really don't strain a grat deal on the kayaks because it gets very tight when I shrink it anyway. The first coat of paint that I apply is extremely thin and soaks in enough to dye the inside of the boat. Maybe it is preventing the absorbsion of water later on. I do it that way simply because my dad did and I have never had a problem so I never changed it.

> What weight of canvas did you use?

> I have had no problems with #10, 15oz. canvas untreated. On a
> 17' kayak you should be able to stretch it 8-9", pick a dry day
> for stretching.

> A friend of mine used 10oz canvas and while it was put on tight
> it sagged as soon as it got damp.