Wet lay up of carbon fiber mats over form

I am looking for methods and suggestions for laying up carbon fiber matting over molds (male and female). Any input will be greatly appreciated.

Well, its a bitch.

First off you should if at all possible vacuum bag into a female mould to get the stongest and most professional looking finished part. You want to vacuum bag into a female as opposed to over a plug (male) because the release and wicking fabrics used in vacuum bagging that absorb excess epoxy leave a nasty finished on surface.

For lay up over a plug, liberally cut your sheets to appox. size trying to make say every third or sheet on a 30 degree angle to the fibre direction to add rigidity to the final part. You could also put in a layer of Kevlar if you would expect any shear (from bolt connections or impact). And be extremely left-wing with the mold release, if not, consider your part a one-off.

Prepare small batches of the epoxy as they will cure slower than one big batch. Gently “bat” the layer to shape then add epoxy, repeat as required. When completed, squeeze out as much epoxy as possible. Final composite parts’ stength are determined by the epoxy to fibre ratio. More epoxy=weaker, heavier part. You could also squeegy out excess every several layers or so.



Thanks for the insight and information. I am actually going to be applying the fabric over a cut out pirce of honeycomb material. I’m assuming that the vacuum bagging technique you described would be the method of choice.
And thank for the information on orientation of the fiber mats. This is going to be a 1:5 scale F1 chassis base so strength is of the utmost importance.
Any other suggestions will be gladly received!
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