: I've been using this in lieu of thickened epoxy on a number of
: projects, and it occurred to me that is might also be useful as
: a skin coating. So I tried it, on a test scrap. What is it? It's
: PL Premium Polyurethane Construction Adhesive.

: This is a completely waterproof, very strong adhesive that sticks
: to a large variety of substances, including wood, metal,
: fiberglass, masonry, ceramic tile, marble, etc. It also adheres
: extremely well to fabric, as it turns out. It's thick, gap
: filling, and comes in a tube that you use with a caulking gun.
: There are two tube sizes, and the smaller produces a bead 30
: lineal feet long.

: I tried it on a scrap of 8oz polyester, which I commonly use for
: skinning kayaks. A 2-3" bead covered about a square foot of
: fabric, and was best applied with a rubber spatula. I put on a
: single coat. It spread quick and easy, though it was difficult
: to tell if I had completely covered an area. It only just
: changed the fabric color - making it look like it had been
: soaked in water. The glue did not migrate through the weave to
: the opposite side of the material. It filled the weave on the
: one side very well.

: I let it dry for a few days (though dry time is much less), then
: examined it. The fabric was stiffer, but still easily fold-able.
: It did not hold a crease, and no cracks or chips were observed.
: I could not scrape it off with a fingernail, a board or then a
: brick. The finish is slightly glossy.

: Then I tossed it into a tub of water - for 4 days. That's at least
: 86 hours longer than I've ever had a kayak continuously in the
: water, FYI.
: After 4 days, the fabric and coating was entirely unchanged. It was
: still flexible, I still could not scrape off the coating, it
: showed no signs of delamination, cracking, peeling, etc. Making
: a cone of the scrap, and filling it with water, still produced
: zero leakage.

: I do not know anything about its UV resistance, or its
: paint-ability. I surmise that dyeing the skin first - a common
: practice - would be the way to go for various skin colors. When
: I get time, I'll paint some and see what happens. It is
: "moisture curing," so perhaps mixing acrylic or
: watercolor paints into it might work to tint it. I'll have to
: experiment with that, too. Calling the manufacturer seems like a
: good idea, as well.

: In sum, my initial trials are leading me to the conclusion that
: this could be a very viable, easy to apply, very tough and - at
: $3-4/tube - not particularly expensive skin coating option. I
: have a boat in mind that I will try it on, and I, of course,
: invite any of you to try it, too - on a piece of scrap, or
: perhaps an entire boat.

: Dave Gentry

: Specs here:
:
: http://files.buildsite.com/dbderived-f/pl/derived_files/derived267834.pdf

Interesting Dave, nice to see that builders are willing to try new things :)

Bill H.