Sculpting Medium Help

[Visser One]

Hello everyone! I'm wondering if anyone can give me some advice on what medium to use for a sculpted helmet (it needs to be wearable when finished). I'm doing a Hermes type helmet, very basic bowl shape, with a curl at the top like in the picture (I'm only doing the top portion). I've thought about plaster, but it I think I'd need a longer drying time than that and I've heard modeling clays are too brittle for something of this size. If anyone has an idea of what material I should use, I'd really appreciate any suggestions! I haven't done any sculpting before so I'll have to stick to things that I can work with just my hands, nothing too tool intensive or complicated. Thanks! (BTW this forum is really awesome, I stumbled upon it when I was googling and am in awe of the work everyone's doing.)

 

[Ozymandius]

If you're just doing a one-off then there are a couple of ways you can go about it. Carve the shape in foam and then hard coat it with fiberglass or urethane resin is the most obvious. Or you can sculpt in epoxy putty over a wire screen.

 

[Visser One]

Wow, the first idea sounds really great! Thanks, I'd never have thought of doing it that way. What kind of foam would you suggest to carve it from? And would I have to paint the fiberglass/ urethane resin on or is there a sprayable version? I thought of sculpting it, but I'm pretty sure I'd need a lot of time so I wouldn't want the medium drying before I'm ready. The foam idea sounds much more manageable so I'll probably do that if I can find a block big enough. Thanks so much Ozymandius!

 

[Ozymandius]

Sorry for taking so long to get back to you on this. Got caught up with work and all.

You can use bead foam (ordinary styrofoam) so long as you seal it before applying the resin. A common cheap way is to stack thick sheets of it up and glue them together with elmers glue. That will give you a big enough block to carve on. To seal it you can use wood glue thinned with water and brushed on in several layers, or brush on one coat and stick on sheets of aluminum foil while the glue is still wet.

The big advantage to bead foam is that once you have your hard shell brushed on, you can then dissolve the styrofoam out with acetone leaving just the shell.

The second type of foam is urethane foam. Carves and sands pretty easily and you can get sharper detail in it. Green floral foam is a cheap and easy to get form of this and you can glue slabs of it together the same as bead foam. It's big upside is that you can directly coat your resin on it without needing to seal it. Can't dissolve it with acetone though.