Hey guys,
While waiting for my vacuum infusion supplies to come in, I was thinking of doing a hand layup of my mold using 5.7oz 2x2 twill carbon fiber. When I was pressing in the twill into the mold to see if it conforms nicely, I noticed that the weave was separating at certain points.
Is there any to prevent the twill from moving? I assume that it just doesn’t like to be pressed into a mold and is more for flatter objects? Or do I just suck?
thanks a bunch
Twill weave is actually for complex moulds, plain weave fabric is for flatter ones. Yours is actually relatively flat and simple.
It takes a bit of practice, you just need to learn to be gentle. Starting from the middle and working your way out helps too. Just be patient with it, and if you aren’t happy with how it goes on then pull that layer off and use it as a backing layer, then start again with a fresh piece for the surface layer.
You can use a light mist of spray adhesive on the back of the fabric to hold it together a bit better, it does limit the drape-ability of the fabric but your mould should be flat enough that this will not pose an issue. Personally I don’t really like doing this, it makes the fabric more difficult to handle and gets adhesive all over your shears when you trim the excess.
Practice practice practice 
Hmm…I’ll try again and see if I can get it to fit better. I too didn’t care for using spray adhesive. Didn’t have any luck before.
I do have 5.7oz 2x2 plain weave cf, but I like the look of the twill better
Your tape isn’t helping either, as it keeps the twill from being able to move freely. Make some relief cuts by snipping the tape in a few spots and see if that helps.
wait… you’re having distortion issues and you say you don’t like spray adhesive?
I guess wet layup is another option… but if you infuse how do you do a part without spray adhesive?
If you don’t “have luck” then practice. That’s not a very complex or contoured part. You can do some very intricate dry layups if you take your time. The first ply needs just a mist over of adhesive. You can also spray the cloth, and then put a piece of plastic on the back and push down nicely. Then it won’t be as likely to distort. Then mist the other side, and lay it up.
one of my good friend makes these same exact part, he does infusion on it. They come out perfect. So I know you can do it! 
we use spray trim lighty in the mold to hold are carbon from moving during the layup before infusion. Im going to try some 8oz 3k carbon as i heard its a tighter weave and less chance of fabric distortion.