Anyone use 'GreatStuff' ie Foam in the can?

[mrbill]

Has anyone used Great Stuff, on a boat? (sold at home depot, as insulation foam)-can says waterproof.I have used this stuff for years on varrious home/auto projects, but wonder if it will absorb water, and end up heavy.I need to futher support a vberth bunk, and was thinking this would be good solution, as it is really sticky, has some strength, and is mold-able, (when I put masking tape on outside, after 15-min. added benifit should be additional floattation.So, my question is does this stuff absorb water? any experience? thanx!

 

[Jack Tyler]

Here's how to tell...

Bill, I've used Great Stuff to help anchor a holding tank under the cabin sole, in conjunction with wooden braces.If you want to determine how absorbant it is, shoot off a bunch in a closed container (e.g. an old shoe box), let it set, peel off the box, and then weight it in a pail of water for a few days. Lift it out and see how long it weeps. (Using the container keeps the number of cavities to a minimum). You'll have some fissures and crevices that will outflow immediately; if it's still dripping for hours, you'll know it absorbs water. It's billed as closed cell, as I recall.Jack

 

[Bob]

A neat little trick

for molding this stuff is to use an ice cube as your "molder". The ice won't stick to that normally stick-to-everything stuff.

 

[Ted]

I've used it on my boat . . .

to install styrofoam flotation in my boat. It does not absorb any significant amounts of water, as it is a closed cell foam.I submerged a cured piece of the stuff overnight to test it out. The next day after being submerged, it floated high.I hope this helps,Ted

 

[Augie Byllott]

Absorbancy of foam in a can

If I wanted to know how absorbent this stuff may be, I'd do this. First, create a cube in a small cardboard box. After the cube has fully cured, peel and weigh it. Next submerge it in water for at least a week. Dry off the outside and then weigh it again. Dividing the latter weight by the original weight would reveal the percentage of water absorption that had occurred.

 

[Mel,]

foam as flotation/insulation/rattle supression

I've used the foam for as long as its been available. As far as I can tell(without the weighting for H2O, etc.)it hasn't assorbed any amount. I've used in our Canoe's & Kayaks for added flotation, also used it in the boat/boats to fill space/flotation, and to stop rattles with out any ill effects in the last 20 yrs or so.