i was thinking of using great stuff

Great Stuff is an aerosol can, single part foam, that skins over and is only suitable for sealing gaps in houses. In breaks down in sunlight. Marshmat posted that information 3 days ago. Great Stuff certainly will not be joining the small expensive club of closed cell, 2 part polyurethane foams that are impervious to water.

http://greatstuff.dow.com/greatstuff/diy/where/index.htm

Pericles

 

I hope the 2-part polyurethane foams have improved over the years since I just filled about 16 cubic feet of voids in the hull of my boat with it. I personally know 2 people, plus myself (and I don't know that many boaters), who removed very heavy, water-logged foam from their late 70's early 80's era boats. Those two never replaced the foam and their boats have never been better (at least lighter and faster) - I was hesitant to pour it back into my hull; I'm still not sure if it was the best idea- but it's done and time will tell. I was very careful to wait for optimal temp and humidity to pour it, though it creates a good bit of its own heat while it's setting up - so controlling temp is hard.
What do they use for foam in buoys and floating piers? especially fuel piers. I think these would be good indicators of how closed cell it remains over time.

 

Tuantom, the foams that were used in that era (1970's and early 80's) were not polyurethane and you're quite correct, they sucked like a hooker outside a GM assembly plant on payday (sorry, couldn't resist).

There are several manufactures of honest to goodness, marine grade, 2 part polyurethane foams, intended for floatation and extremely resistant to moisture, chemicals, fuels, etc.

Pericles, I get my foam from FiberGalss Coatings, Inc. (www.fgci.com) They have the specs available and also sell a 4 pound foam as well as the 2 and 8. You may also want to try Epoxy Products brand of foam too.

I'm in complete agreement on foaming in tanks (frankly a lot of other things too). It's a guarantee for future repairs at least, possibly causing much more then just a leak.

Maybe Rhino Coating the tanks (completely abated first), then foam . . .

 

Or use Pre-Kote on the tank and epoxy. They use it on airplanes in place of aladine.

 

PAR,

Epoxy Products, these guys? http://www.epoxyproducts.co.uk/

Pericles

 

Sorry Pericles, I misquoted the company name.

http://www.epoxysystems.com/products.htm

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