[Christ]

Originally Posted by 3-Wheeler

Yes, the pink/blue Styrofoam is MUCH better than the white packing foam.

The white stuff has a lower density, and will allow it to get crushed very easily, even with a layer or two of fiberglass cloth over the outside.

The pink/blue Styrofoam is better, since it has a higher density.

While being picky when I say this, but for best results you would want to find industrial foams that are two to five times more dense than Styrofoam.

IndyCar and F1 race cars use Hexcel aluminum honeycomb for really high quality and really expensive carbon composite structures.

I stick with Styrofoam for ease of purchase and it's workability.

Speaking of which, I use the following tools almost exclusively for shaping/working with foam:

1) Hand saw (for cutting wood, to make long foam cuts)
2) Hack saw blade
3) 1/2 round rasp file
4) 60 grit sand paper glued to 4 inch square foam block
5) 120 grit (ditto)
6) Elmers Wood Glue for gluing foam blocks together
7) 1.5 inch long wood screws for holding blocks together until dry

Jim.

Florist's foam (green, medium density) works perfectly for forms. It breaks into smaller pieces fairly easily, and it's dense enough that you can sand/cut it cleanly, but you can also just push shapes into it (like if you wanted a certain ball shape, you could just push the face of the ball into the foam) which saves alot of work on custom/complex contours.

You can get it in blocks at hobby shops and art/craft stores (Michael's comes to mind, locally).

IIRC, it doesn't glue very well except with hot glues, which actually allow you to glue two pieces flush because the glue melts the foam enough to allow both pieces to face off on each other. You might be able to get away with a brushed layer of Elmer's though.