Composites noob plaster mold question

[miyagisan]

Hello all. I'm very interested in working with carbon fiber for automotive applications. My goal is to produce aesthetic and structural pieces. I think I've decided on vacuum infusion since I can't afford a large autoclave for pregreg. But before I go out and buy equipment and materials, I want to practice making molds first. I would very much like to use plaster molds versus fiberglass, but I'm not sure whether or not it is a suitable material for vacuum-infusion carbon fiber. If it is, what type would you recommend?

Any information you have would be greatly appreciated!

 

[patprimmer]

Have you tried to obtain information from resin, prepreg and fibre suppliers.

Have you tried doing a google search.

Regards

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[miyagisan]

I've been looking for information. It seems like fiberglass is popular for molds. I don't see why plaster wouldn't work, but I've never worked with composites, let alone carbon, so I thought I would seek out people that have more experience

 

[patprimmer]

Whether fibre glass and carbon fibre, it makes no difference to the mould.

Fibre glass moulds will be a lot lighter and stronger than plaster.

It will be difficult to get good mould release from a plaster mould, so a lot of mould release wax might be needed. This might reduce the surface gloss and therefore require more effort in the finishing of the part.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[samplesecond]

You will have reliability/structural issues using plaster as a mold. It is handy for taking a 'splash', but I always build my molds out of something more robust.