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Re: Canvas treatment?
By:Steve McDonald
Date: 3/28/2000, 7:51 am
In Response To: Re: Canvas treatment? (Ben-B)

> I'm done. The deck is in, I've applied Thompson Water Seal as suggested
> and will start painting in a week. I was hoping that the canvas will
> shrink a little but it does not seem to happen with TWS (the deck is a
> little loose). I should have wetted the canvas with hot water prior to
> saturating with TMS. Is the canvas going to shrink in the long term or
> not?

> Thanks again for your reponses

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Wetting Canvas for Tightening:

My experience with canvas is that although it may shrink a bit when it's wetted and unstretched, if it has been tightly stretched on a boat, this may allow it to do the opposite and end up looser along the stretch lines, when it dries out.

I always had bad luck with loosened ripples on my boats, when I used oil-based paint. After I switched to latex paint for the first two coats and rubbed it in well with my fingers, the looseness problem ended. I let the boat hang from 6 bike-tube straps, hooked down its center deck line, while the hull dries. The elastic allows the length of all of them to even out and support the weight almost equally. The weight of the painted canvas between the stringers won't sag inward and get pulled slightly around the edges of the wood, in this way. After a week of curing, I put 2 or 3 finish coats of oil paint on the outside. I also put 1 latex coat on the canvas inside, after I turn the hull over, immediately after applying the first outside latex coat. Later, I put on 1 oil coat inside. After I did this, I once added a 4 oz. layer of S-Glass cloth, with DeraKane 8084 Vinylester resin, on the outside of the hull, after the paint had cured for a month. This skin stayed usable for 20 years, 4 times the usual lifespan for canvas with nothing but paint. I had to replace the non-fiberglassed deck skin a couple of times, during that period. If you soak vinylester or polyester resin directly into bare, stretched canvas, it's guaranteed to ripple up and will lose a lot of its flexibility and resistance to damage.

Steve McDonald

Messages In This Thread

Canvas treatment?
Ben-B -- 3/25/2000, 7:00 pm
Re: Canvas treatment?
Ben-B -- 3/26/2000, 4:28 pm
Re: Canvas treatment?
Steve McDonald -- 3/28/2000, 7:51 am
Re: Canvas treatment?
Bram -- 3/26/2000, 10:03 am
Re: Canvas treatment?
Jay Babina -- 3/26/2000, 9:42 am
Re: Canvas treatment?
Tom -- 3/26/2000, 1:33 am
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L. Robinson -- 3/26/2000, 10:32 pm
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Jason -- 3/27/2000, 10:27 am