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Looking for Suggestions on Innovative Design, Filling to shells with foam

Looking for Suggestions on Innovative Design, Filling to shells with foam

Looking for Suggestions on Innovative Design, Filling to shells with foam

Not going to go in much detail here. I've been given a profile and a length. See the attached sketch.

The idea is that the inner and outer walls will be highly finished surfaces. The outer wall will have gel-coat facing outward, the inner wall will have gel-coat facing inward. This will be used to produce a very slick stream-lined effect both inside and out. This will likely be done by placing an inner mandrel inside the outer mold after both have been gel-coated and glassed.

We are looking to then introduce some time of filling agent that will produce a very lightweight but stable structure. It will not be transmitting much force or load but cannot interfere with the sleekness of the structure. Your typical Polyurethane foam will vary in density if we just pour it in and you'll be able to see this on the outside. Such a large volume of Polyurethane foam will also exotherm a good bit, which will cause more problems with maintaining a sleek look.

We'd like to have the old polyester foam that was used back in the 70's but has not been available for the last 20 years. So far its just a brain-storming concept. We're open to all suggestions. Just wondering what suggestions anyone else may have?

Even if you could get some bio-agent that grows and produces a coral-like material in a reasonable amount of time, heh. Anything at all that might do what were looking for....

We're looking for a material/method to fill is that has the following properties:
- Low density
- Low exotherm
- Good thermal insulation properties
- moderate stiffness
- stable
- can produce uniform density
- fairly slow-curing

Any input will be appreciated.


RE: Looking for Suggestions on Innovative Design, Filling to shells with foam

This sounds promising. It's an in-situ polyester foam for marine applications.


“There are two different types of open cell foam available: the fully reticulated foam and the in situ reticulated foam, which our company manufactures,” McRee says. “Full reticulated foam is actually the process in which the foam is poured. The buns are taken to a special chamber where they are blown open. The in situ foam that we pour is a blend of polyester and polyether technology—we do not have the blown-out type. The cost of the blow-out-chamber reticulated foam is approximately double that of the in situ process.”

Dr. Chris DeArmitt

Plastics consultant to the Fortune 500: www.phantomplastics.com

Webinars on plastics, fillers & impact modification: www.plastictraining.com

RE: Looking for Suggestions on Innovative Design, Filling to shells with foam

About polystyrene beads

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