Carbon Fiber Repair Question?

[Mylesstyles]

Does anyone have any experience in repairing/sanding/or repainting cabon fiber parts? My R1100S front fender is scratched and I want to try and sand it smooth and then recoat the resin or paint it black. I was hoping to get some expert advice or even horror stories from your attempts at repairing carbon fiber parts.

 

Thanks,

 

Myles

[John Dickens]

Does the scratch go through to the carbon fibre material itself or is it just in the surface resin.

 

If it's only the clear resin coat you may be able to get away with polishing the scratch out or at worst lightly abrading the surface and spraying with clear lacquer.

 

If the actual carbon fabric is damaged then a respray is best.

 

Carbon fibre is usually used with an epoxy resin rather than polyester as for GRP but either way this is the way to go.

I would fill the damage with 'bondo' or similar, rub down the whole surface with 400 grit paper, use a specific plastics primer then spray the whole thing in my chosen colour.

[FlyingJoe]

I have built several carbon fiber parts for an experimental plane and fixed my front fairing once from a crash. It is not really different than fiberglass except 'wetting' it with epoxy is a little harder and by color alone one cannot tell if it is sufficiently 'wetted'. If it is cracked through, take it off, sand the underside and lay down either 2 pieces of fiberglass or one of carbon. If you want it to remain all carbon you can purchase a yard of it from aircraft spruce

http://www.aircraftspruce.com/menus/cm/carbonfiber.html

It won't be cheap once you get some epoxy as well.

 

You can probably get away with just filling in the crack with jb-weld. And as mentioned then the typical approach of bondo, 400 grit wet, prime, spray, buff.