Anyone worked with carbon fiber?

[Pappy]

like most Dodge trucks, the plastic dashboard on my Ram has cracked and is in 3 pieces.

My initial idea is to remove it and build a quick mold to hold it in shape while I epoxy the cracks and 'glass the inside to reinforce it.

I also thought about bonding a layer of cross weave carbon fiber to the outside, both for looks and added strength. All the tutorials and info I can find on carbon fiber lay up is either in a female mold (Plug) or vacuum bagged.

Anyone know if it can be hand layed as a top layer with decent results?

[gsmittle]

Don't quote me on this, but I seem to recall reading about laying up carbon fiber much like fiberglass on wooden canoes. I THINK I read about the process in one canoe-building book or another.

g.

[Tom Slick]

From the little bit I've messed with you can lay it up like fiberglass but you typically use epoxy resin instead of polyester resin. For a dash, make sure the resin is UV resistant.

Bagging pulls the air bubbles out and makes it conform to the mold better but that's for any composite, not just carbon fiber.

[cwsmith]

If I recall correctly, it seems that Burt Rutan built the fuselage and wing structure on a few of his airplanes using carbon fiber cloth. I recall watching a program several years ago, when they were hand layering the fiber and applying the advesive chemistry (expoxy or other bonding activator).

It seems to me that hand layering was the first applications of carbon fiber, where it was well suited to single production tasks. Only in production of multiple parts would a mold come into play, I would think.

I used to have a technical book on carbon fiber... I'll have to see where in the library my wife stuck it.

CWS

[JSUPreston]

LMCtruck.com?

[cwsmith]

Pappy,

I looked, but it appears that my book is at the other house and unfortunately I won't be returning there until this next week.

However, if you do a "Google" for "working with carbon fiber" you'll get a number of good hits, including the following home shop example from "Make" magazine: http://www.make-digital.com/make/vol09/?pg=167#pg167

I hope this helps,

CWS

[sscherin]

how large of an area do you plan to cover? CF cloth isn't exactly cheep.. like $30-$100 pr yard..

there are places that sell black fiberglass cloth that looks close to CF at a lower cost.

Look into US composites 635 epoxy resin.. They sell it in quarts. 1/2 gallon and larger sizes including hardener.. choose from fast 10-15 min pot life, medium (25 min) and slow (60 min) hardeners..

The polyester resin you find a the box stores is horrible nasty stuff to work with (high VOC) as it contains liquid styrene.

one recommended method for wetting out the cloth is to squeegee out the resin into the cloth between layers of poly drop cloth.. cut to size, peel, apply and smooth with a bondo spreader. blot off excess resin and let it cure..

you could add a layer of peel ply and blotting material before it cures.. Let it fully cure and remove the peel ply.. It will leave a surface that will be ready to clear coat with little sanding.

I'd experiment with small simple pieces before taking on the dash..

the EAA has some good composite videos
http://www.eaavideo.org/video.aspx?v=82647984001

Ohh CF cloth is nasty like fiberglass. wear long sleeves and a dust mask..
DONT breathe CF dust.. always sand with protection.

don't fold CF cloth.. roll it up on a tube. folding damages the tows (threads) and messes up the weave.

[lrogers]

I've done some hand lay ups using epoxy and CF to reenforce critical areas on several of my hellicopters, but these were very small. Nearly all of the larger lay ups I've seen have involved the vaccuum bag method.