Help! Composite Mould Manufacture

[antsals]

Has anyone any idea what the best material would be for mould manufacture for composite parts? I have been doing some vacuum bagging of parts but want to CNC machine some custom moulds that I can use a few times?

I want to ensure a high accurate part and very smooth surface.

Any help would be good.

Thanks
Ant

[ckelloug]

If accuracy and finish are important, I'd suggest talking with a tool steel vendor about a tool steel which meets your polish criteria.

[CarbonKevin]

Tooling epoxy might be better bang for your buck, depending on how many times it's going to be used. It costs less than tool steel, less expensive to machine than tool steel, and still is very precise and can achieve good surface finishes.

Out of curiosity, though, what sort of parts are you building? Are they strictly cosmetic? Structural? Structural with cosmetic requirements? If you're really going for "the look", there's going to be sanding and clear coating after layup, so how perfect does the mould really have to be?

[ImanCarrot]

If you're going for an optical finish get the mold tool diamond turned in brass or OFHC copper- perfect finish with a Peak to Valley form error of sub micron accuracy (that's less than 1/1000th of a mm). I'd do it for you but I'm stacked up here.