Hi all,

I have some experience with composites, mainly with carbon skinning, but I'm wanting to start producing more advanced resin-infused parts. First on the list is to create an A-pillar mounted gauge pod for a car (I'll assume you all know what one of those looks like). My projects to date have suggested that carbon fabric simply isn't flexible enough to be manipulated into such complex concave shapes (the finished part would be convex but obviously the mold is concave) as a single sheet. With a gauge pod the only benefit of using carbon fibre would be cosmetic, so I don't really want the weave joins that using multiple sheets would cause. Am I missing some magic technique that would allow such a shape to be layed as a single sheet, or should I just stop wasting my time and make it out of CSM and spray-paint it instead?

Thanks fo any advice.

Hi Danny,

With something small and awkward like the guage pod you're describing it might simply be that it would be too difficult to get right to bother with although to be honest, if you want to do it enough then anything is possible, given the right techniques. Other parts lend themselves a lot better to being made out of carbon fibre and so you might find these more rewarding to work on but like I say, if you really want to, anything can be done and look amazing.

If the shape dictates that a single layer of carbon cloth simply could not follow the contours or that if it did it would be so distorted as to look awful then you will need cut-lines. Cut lines in dry carbon cloth will always tend to fray and look messy and so you will need to stiffen the fabric (or use a pre-stiffened fabric like our ProFinish Carbon Fibre Cloth). Ways that you can stiffen fabric yourself would be to spray it lightly with hairspray or to mix up some epoxy resin and hardener, thin it with metholated sprits and then spray it through a spritzer bottle onto the fabric before allowing it to cure. All of these methods will, to a better or worse degree, allow you to make sharp, neat cut-lines in the cloth, allowing you to line the inside of your mould with multiple panels of fabric (like you would see on a pre-preg part). If the lines are neat and are in logical places then they should look perfectly acceptable. There are no other options, even if that guage pod was a £1000 part made by a forumula one team in an autoclave, it would have those cut lines - they're the very nature of the material.

I hope this helps.

Best regards, Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales