Carbon Fiber, Specifications? Options

[Todd Enlund]

I want to make a few Carbon Fiber parts for my car... but I'm trying to decide on which fabric to purchase. Twill vs plain weave, weight, and tow size. I will be using the CF primarily for it's cosmetic value, so appearance is my primary concern. I believe that twill is my choice for weave, and I'd prefer as light a weight as possible... but I'm not sure what "tow size" is. I'm guessing that it has something to do with the size of the weave, and the heavier the cloth, the larger the tow. For example, 5.7oz cloth has a 3K tow, and 11oz cloth has a 6K tow. 5.7oz would be my preference, but I'm concerned that the weave may be smaller than I want as far as appearance goes, and I may be better off with 11oz.

Anyone have any experience, and can offer some advice?

I plan on vacuum bagging with epoxy resin.

[Grngoat]

3K, 6K, whatever refers to the number of individual fibers in each tow. So 3K tows will be half the size of 6K tows, resulting in a finer grid. You probably want something larger if you want to see the weave from some distance away. Plain weave is what you normally see on automotive stuff, so it's what people "think" carbon fiber looks like. But 5HS is stronger and more typically used on real structural parts. Strength wouldn't matter in your application though.