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Re: Skin-on-Frame: Material - rubber coating?
By:Paul G. Jacobson
Date: 5/15/2008, 7:26 pm
In Response To: Skin-on-Frame: Material - rubber coating? (prasad bhatla)

: Always wondered if a SOF skin can be coated with some form of rubber.

: And look what I found : www.liquidrubber.ca . . .

: Wonder what the price is?-checking on this.

: If one loves black or brown kayaks, I suppose one may consider this product
: -- these are the only 2 color choices.

Consider Sno-cote, an elastomeric roofing compound, or one of the similar products. These are water-based materials, usually in white, designed for roofing applications. I wrote about this a few years ago. Here is a link to that posting:
http://www.kayakforum.com/cgi-bin/Building/Archive20.pl/noframes/read/27886

That post mentions my test with white topsides paint over the Sno-cote. The canvas (mostly) rotted away several years ago, but the paint and the elastomeric roofing compound were good for the life of the base fabric. The few scraps still hanging around are waterproof.

Somethning I didn't do at the time was to treat the canvas with a mildewcide. The painted surface stayed good, but the inside of the boat turned black from mildew, and that started the rot in the canvas. Next time I go that route I'll add a mildew-preventative to the paint or elastomeric roofing material (I see Home Depot has pouches of a dry chemical that you just mix in for this) and I'll treat the inside of the boat with an occasional flush of a borax solution. That should stretch the life of the skin a few more years. As it is I think 3 to 5 years is a good life for a canvas skin on a boat stored outside and uncovered. Protect it better and it will last longer.

The roofing material (sno-cote, etc) comes in two thicknesses, or viscosities. One is a "brush" grade, which has the consistency, and smell of a latex paint. it goes on fast and gives a smooth thin coat. I put on three coats, which filled the fabric weave pretty well. It bonds really well to canvas. (you odn;t need to thin it first) I've never seen any evidence of delamination.

The other is a "trowel" grade, which I haven't used. I understand it can be thinned somewhat with water. It goes on a lot thicker. This stuff is usually applied with a squeegee to a roof to give a thick coating.

If you build this stuff up to get a coating which is about 1.5mm to 2mm, or somewhere around 1/16th to 1/10th inch then you have a VERY strong and flexible sheet of rubber, which just happes to have some canvas under it. Using the paint grade of material you would need to put on a lot of coats to get something this thick, but with the trowel grade stuff you might do the job on the second coat! On a roof this stuff has a lifespan of over 20 years. UV does not seem to bother it.

Depending on the brand, store, quantity and sales, I've seen various elastomeric roofing compounds selling for $16 to $35 a gallon. Last time I bought some I paid about $20. I have seen it packaged in quarts, for about $7 to $9.

Hope this helps

PGJ

Messages In This Thread

Skin-on-Frame: Material - rubber coating?
prasad bhatla -- 5/15/2008, 12:30 pm
Re: Skin-on-Frame: Material - rubber coating?
Paul G. Jacobson -- 5/15/2008, 7:26 pm
Re: Skin-on-Frame: Material - rubber coating? *LINK*
Mike Bielski -- 5/16/2008, 9:29 am
Look for snowroof here
Paul G. Jacobson -- 5/21/2008, 6:24 pm
Re: Skin-on-Frame: Material - rubber coating?
Paul G. Jacobson -- 5/21/2008, 6:14 pm
Re: Skin-on-Frame: Material - rubber coating?-----
Mike Bielski------WebKitFormBoundarys5T0rHO+hnUNvS -- 5/15/2008, 1:39 pm
Re: Skin-on-Frame: Material - rubber coating?-----
Tom Yost -- 5/15/2008, 6:23 pm
Re: Skin-on-Frame: Material - rubber coating?
Aaron H -- 5/15/2008, 12:57 pm