Mold Material

[NWH]

Can any one tell me why Carbon pre preg material is used for the production of Molds for Carbon Chassis. I was reading an artical in racecar eng and it showed the Force hillclimbe chassis being made form Carbon fiber tooling pre preg. What would be wrong with good old glass fiber? Also lola make most of there body molds from carbon aswell. I understand the reason for epoxy resin being used over Polyester it shrinks less and is stronger. But what would be wrong with using a Vinylester high temp zero shrink resin with glass fiber?

[Dave Brand]

Originally Posted by NWH

I was reading an artical in racecar eng and it showed the Force hillclimbe chassis being made form Carbon fiber tooling pre preg. What would be wrong with good old glass fiber?

Weight for weight, carbon fibre is much stronger than glass fibre; that's why it's used.

[richard_sykes]

Do you mean the actual mold or the chassis which they take off the mold?

The chassis would not only be stronger but, it is a lot stiffer too.

[StephenRae]

The same materials are used for the mould and the finished product because they react to heat in the same way.

[richard_sykes]

I was going to say, the fibreglass might not like the autoclave.

[Dave Brand]

Memo to self:

Read the question......it's 'moulds', not 'mouldings'!

[GolddustMini]

add to the fact that if using prepreg carbonfibre layup is a damnsite less messy than glassfibre, reducing the mess created when creating the moulds.

but yes its more likely to be due to heat exppansion of the material when in the oven, leading to a better quality finished product