Corafoam U 150… Datasheet here:
Looks like decent specifications, somewhere between R3312 and R3318 foams. No pressure test data but compression strength and water absorption look good.
The main attraction is cost and availability, this material is stocked at the local sign maker shop and they can cut and/or CNC it to order…
Thoughts?
The foam has a nice density … 0.24 g/cc so it will float for sure!
I like that it is closed cell and the durometer is high also. There is a good chance that this stuff will handle pretty well to a good depth. Only way to see how much it shrinks is to actually pressure test it.
Send me some, I can crush it 
Seriously, if the price is right for you, have them cut you up whatever you want and give it a try. I would make sure that you still got enough rear to drive to the surface just in case but the stuff sounds like it has a lot of promise.
Tim,
They are shipping us some samples. We will pressure test them when we get them and let you know the results.
Best,
Jonathan
Jonathan,
Well that’s intriguing news. Thanks guys, I look forward to seeing the results!
Tim
Tim,
We just finished up the first test which was Corafoam U-150 at 100 meters overnight. We used a 200 gram block of the foam and in the morning it weighed a little over 400 grams. We can test to a little shallower, but I doubt the Corafoam will work at all as sub-sea buoyancy foam.
For comparison, the General Plastics R-3312 would gain less than 1 gram in a similar test.
Best,
Jonathan
Hi Jonathan,
Thanks very much for the testing and follow-up. Surprising and disappointing results, but it’s good to know it’s not suitable.
I can try to find out what the foam is that we use - been using it for years for shallow stuff with no problems.
Tim,
It was no problem. We are looking for a cheaper foam that performs similarly to the stuff we are currently using. We had tested a couple of other closed-cell rigid polyurethane foams before, and so far the only foams that have worked were advertised as subsea foam (which really jacks the price up).
If you find any more, send them our way and we’ll give them a test.
Best,
Jonathan