Foam Sandwitch

[mcollins07]

What are your recommendations for synthetic foam core materials which are compatible with West System epoxy? I prefer closed cell, but looking for something low cost and readily available in small quantities for prototyping. Supplied at Home Depot, Lowes, etc. perferably. What about the isocynate used for house insulation. Has anyone tried bubble wrap? I think buble wrap is polyethelene. Availability by UPS is fine if price is right and available in small quantities.

[mcollins07]

What foams have you successfully used with West System epoxy system?

[johnnyv]

Epoxy doesn't stick well to cured polyurethane, polyurethane sticks well to cured epoxy.
First case you have a physical bond only, second case you have a chemical bond.

polyurethane or epoxy don't stick to polyethylene, infact it makes a fantastic mold material no release agent required.

[mcollins07]

Thanks Johnny

that's very helpful information. I expect to experiment with some of these materials, but your direction will save a lot of time.

[waikikin]

What is it that your making? Seems like your using an expensive resin but looking for cheap foam? Try finding someone local that does surfboard supplies, surfblank foam shapes quick & easy & goes well with much quicker to use polyester resins- might mean quicker prototyping for you, but with out knowing(maybe cutting edge secret I hope) what your making its hard to say. Regards from Jeff

[mcollins07]

Originally Posted by waikikin

What is it that your making? Seems like your using an expensive resin but looking for cheap foam? ... from Jeff

I am prototyping various designs. For several years, I have been making paper models (6" - 12") by printing panels on cardstock and taping these together. I'm now wanting to move up to the next scale of about 2' - 4'.
Also, I would like to develop materials systems which would allow full scale constuction or at least plug/prototype construction.

Although some of my designs are specific, many are experiments to explore design forces/concepts. For examples deeper forefoot
One of my practical designs is a dinghy that will fit well on the foredeck of my 37' ketch.

I want to use expoxy because of its ability to glue plywood. I thought it would be a better glue for various materials, allowing more flexibility in choice of materials. Perhaps expoxy is not the great glue that I thought it would be?

Do you know what material the surfblanks are usually made of?

[svfrolic]

You might want to take a look at:
http://www.fiberglasssupply.com/
http://www.epoxyproducts.com/
http://www.surfersteve.com/introduction.htm

Matt