MikeSell

My Feedback: (2)

I know that suppliers often recommend special sizzors for cutting fiberglass, kevlar and carbon fiber cloth. I've sawed fiberglass after it was laid up and it took quite a toll on my saw blades. What should I use to cut carbon fiber sheet? Is it easier to cut than kevlar?

Jetman007

My Feedback: (6)

We use a wet tile saw to make straight cuts in CF plates. Can also cut shapes with a carbide or diamond sputtered bits or similar saws in a rotary tool (Dremel or RotoZip work well).

Wear a dust mask!

barto

Do you mean, how do you cut in cloth? Just use a desent pair of scissors and wear some gloves because the little pieces of carbon can get in your skin and then it can infect pretty badly.

MikeSell

My Feedback: (2)

I was looking for information on both forms, but was more concerned with laid up sheets. I thought that the material would quickly dispatch my saw blades and that I might have to get a carbide or diamond impregnated blade.

patternwannabee

My Feedback: (1)

I, too, am looking for a better way to cut composites.

Just laid up a couple of landing gear. The CF cloth (5 oz) was easy to cut using a rotary cutter, but the Kevlar was nasty. I used scissors, but it was VERY slow going.

After the 2 gear were laid up, I've broken 1 band saw blade, and ruined 2 more. I'll have to try a diamond cutoff wheel next if there is such a thing.

I suspect it was mostly the Kevlar that caused the problems. They don't use these in bulletproof vests for nothing.

ptxman

My Feedback: (2)

My experience on cuting raw cloth is that e-glass, s-glass & carbon are all similar in that almost any decent quality shear or rotary cutter will work just fine. An inexpensive pair of scissors will just wear out faster & have to be resharpened sooner than high quality shears.

Cutting kevlar cloth is a whole different animal. Just for kicks, try & cut some with regular scissors. Its about as effective as sanding your living room rug. In order to do it properly you want kevlar shears which is a combination of serrations along the blade edge & a slightly blunter blade angle, the former being more important. Lots of guys, myself included, are cutting light weigt 1 - 2 oz kevlar by simply 'regrinding' ordinary shears on a belt/disc type sander, maybe 80-100 grit or so. This makes the desired micro serrations which is important to grasp the fibers as they are cutting vs letting them slip along the blade like regular shears. You can use a cheap pair of scissors for light weight stuff, no problem. Dont be too agressive in terms of reprofiling, just follow the shape of the existing blades. I was skeptical when I first read about it but it works amazingly well.

When it comes to heavier weight kevlar like 5 oz/yd +, these homebrew shears start to fall a bit short & not make the grade. Then you want to pursue professional kevlar shears like German Robuso/Sollingen (?sp?) which are top notch & avalable in may sizes. I have some of these too & they are excellent. You can buy kevlar shears in the USA but they tend to either be spendy & size limited if they are quality tools.

In the case of trimming semi-cured epoxy impregnated kevlar (like in a layup situation) ordinary brand new = sharp razors work pretty good. Cutting cured composites is hard on any normal high speed tools, you want carbide or diamond. Cutting a cured kevlar layup seems to alway sleave a slightly fuzzy edge which is kind of a pain.

patternwannabee

My Feedback: (1)

Good info. Thanks ptxman