Pourable foam

of course it must be suitable for marine use. the 16lb density is hard and brittle
but not the lighter weights. also, polyurethane gives off less toxic gas when burnt then wood frame, think it is something like 20 minutes escape time before death.

 

It always makes me nervous when a conversation starts out with "of course..." It almost always isn't so. ;-)

To the best of my knowledge, pourable foam is not available in 16 lb/ft density. This would be extremely hard foam--harder than any hardwood. Pour in place is usually called 4 lb foam, and in fact expands to between 4 and 7 lbs density (an earlier poster cites 7.5 oz in a half-gallon can. This would equate to about 7 lbs./ft.)

"Marine use" covers a large amount of ground. PU foam is perfectly suitable for docks, insulation and floatation. It is widely used as upholstery stuffing, and as spray-on insulation for fishboat holds. It is manifestly unsuitable for structural use, as for foam-core glass or carbon hulls. It is brittle and friable; quickly delaminates and separates from the glass skins. Proper boatbuilding foams like Divynicell or Klegecell and many others are far, far superior.

As to fire retardancy; yes it is possible to add fire retardants to urethane foam which raises its combustion temperature. I am not aware of any ordinarily-available pour in place "marine" foams which are fire-rated, however. My point was not about flamability of such foams, however, but about their toxic outgassing, which happens at much lower temperatures. Talk to any firefighter, ask him which is more dangerous; polyurethane foams or pine.

Dave

 

Here's a material safety data sheet for pour-in-place foam. Note the firefighting recommendations: http://www.fibreglast.com/documents/366.pdf

 

http://www.shopmaninc.com/foam.html
16 lb. can be had here!!!!!!

http://www.swdurethane.com/SWDpages/pdfs/burning_schedule.pdf
won't kill ya as fast as burning wood.

Can't imagine there's a company anywhere in the world building trailers with polyurethane, my guess is they'd be using the cheapest foam possible like the rest of the material they use in those things.

Goodness, if a burning trailer got sucked up by a tornado it would look like a giant flaming marshmello flying through the air.

 

Whatever,

What will you use 16 lb 2-part foam for? They build daggerboards of 10 lb foam, and that's very, very carefully manufactured to exacting tolerances in order to deliver precisely engineered performance. What could you possibly build, needing this hardness but without any quality control, that you'd be willing to pay this outrageous price for ($53/cubic foot)?

And then you've got a foam manufacturer's study showing I will die almost 12/100 of a minute later of PU foam gassing in a fire than of wood. Unspecified species of wood, unspecified foam content, unspecified test conditions, unspecified temperature. There are wood species whose dust will kill you at room temperature, but yep, you got me.

But nevermind, you win the bet. Nice Google work. Good luck with your, er, project.

Dave

 

This link may help you
http://www.foampower.com/products/slow_rise.html

 

Pourable Polyurethane Foam

the slow rise looks interesting for floatation, thx.

 

2 1/2 yrs later has anyone tried the slow rise foam yet?

 

Final Results of 1 years test (2/05 thru ?) ??

Bob,

What were the final results of your 2-part foam submerged in a salt water lobster tank for a year?

What type of foam did you use?

We're looking at filling the hollow keel in a Trojan Sportfish, which tends to hold smelly water.

Thank you in advance,
Captain Ross

 

Capt. Its been awhile since I started this test but remember it very well. I placed the foam in the tank for a year and then pulled it out held it in Maine weather for several months to return it to the tank for 6 more months. Trying to simulate on the hard over a nothern winter haul out. My test results record that this stuff is bullet proof for a boatbuilding material. A little tricky to use. Leave plenty of room to expand. Purchased it through Fiberglass Coatings down in St Pete Fla. I also used the 8lb per sq ft. Site posted below

http://www.fgci.com/