Exotic materials

[Kongen]

I saw this link in the system pic gallery www.selectproducts.com and checked it out. I can see in their product range that they sell carbon fiber epoxy. Is this material suitable for making speakers? they also have carbonfiber sheets... perhhaps laminating theese would give a good material?

Does anyone know how to use these different materials? from my point of view the epoxy stuff seems the best (probably the cheapest also) choice if you could simply make a mold and pour in the epoxy and end up with a stiff, inert speaker (perhaps do a b&w 800-series look without having to do a laminated structure - perhaps even go for the round midrange enclosure)...


Kongen

[Snickers-is]

I think you can treat these matherials like glass fibre. Think of how they build a boat. You make a shape and put glass fibre sheets in it. Then you poor liquid plastic (non-hardened acryl i think) over the sheets.

[dwk123]

Snickers is mostly right. The area of composites is actually pretty involved, but the basic idea is dead-easy: the combination of a resin and some fibers bound together to form a structure that is stiffer and stronger than either could be alone.

You use carbon fiber and expoy resin exactly the way you would use 'normal' fiberglass materials (polyester resin and glass mat). The benefit of carbon fiber over fiberglass is that it is stronger and lighter for a given thickness. It's generally tougher to work with, though.

Is it useful for speaker building? Sure, but it's far more complicated than just pouring resin into a mold - pure resin with no fiber reinforcement is a poor material to build speakers with. Getting good/professional level results is not easy, and it takes a LOT of time.

Epoxy/carbon fiber will be WAY more expensive than normal fiberglass, and it's not obvious that it would be any better than normal fiberglass unless you move your speakers all the time.

I'd suggest getting a book on composite techniques or scanning the web for HOWTO's. You'll find most information in relation to car building/restoration, since that is where most 'DIY' use of fiberglass and associate materials is.

[454Casull]

You don't pour the resin over the layup, you brush it on. Or, you can get the pre-impregnated stuff.

Works best if you use a vacuum bag autoclave.

[Kongen]

I thought that the carbon fiber epoxy stuff was a kind of resin with carbon fibres in it. But what you are saying is that it is just a material for "gluing" the sheets together as you do with glass fiber (i've done that once and it was not a success ).

But what about the resins then? are there any available resins which you "just" pour into a mold and leave to cure? something which is useable for speakers?

kongen

[Snickers-is]

Try to find someone building boats, or someone delivering equipment for moulding such things.