Hello everybody,

I am going to make a mould for something shaped like the half of a car door. Usually I would go for the unimould system but now I am thinking of using the tooling prepreg to have the option to use prepreg for the part.

Any advises or ideas/pro/cons?

Thanks!

You have to consider your flanging and barriers. Vacuum processed moulds like pre-preg and infusion require solid flanges, they cant be temporary flanges as you might make for a wet-laid Unimould tool.

So realistically, you cant use vacuum processed moulds to replicate an OEM vehicle panel. To do so, you would first need to build wet-laid moulds in the regular fashion (although you can get away with doing cheaper 'splash' moulds), then use those moulds to remake a male version of the panel but this time with flanges built onto it. Then you can use these new patterns to make resin infused or pre-preg moulds. By the time you've gone to all this effort, a simple wet-laid epoxy mould would be significantly cheaper and easier.

I do this sort of thing fairly often for production moulds, but never for a once off.

So what you see is a problem with the flanges because of the vacuum process? I already made some moulds with the high temp epoxy and I used temporary flanges, that worked pretty well.

Yes, any wet-laid moulds will work fine with temporary flanges, doesnt matter what resin you're using.

As soon as you try to pull full vacuum on anything with temporary flanges, it will warp and pull the flanges off the part. If you're using a material like coreflute for your flanges then this will crush under the vacuum pressure.