Talk Composites - The Forum for Advanced Composites

Preventing fraying

http://www.talkcomposites.com/Topic10101.aspx

By KeyboardWarrior - 3/8/2014 12:04:49 PM

Hi there.

I'm going to be constructing a complex shape with the external cosmetic layer of reinforcement being red CF. I've worked out how to cut almost the entire shape as a single large piece (140cm x 70cm to give a rough idea of scale), and with all the cuts being perpendicular to minimise issues with fraying.

However that's not quite perfect, and the item will need two rather more fiddly small pieces to complete, with really precise cuts at odd angles. The concern is that fraying will be impossible to avoid and that those bits will spoil an otherwise perfect cosmetic part. Is there a trick here?

Can I spray a small piece with some sort of glue before cutting that will keep it together without any fraying, and are there any particular pitfalls to look out for to avoid spoiling the cosmetic appearance.

Thanks in advance.
By carbon Booms - 3/15/2014 2:35:07 PM

I have a technique that I use to put a very thin layer of toilet tissue onto the carbon mat.  You will see it all here:

https://www.youtube.com/watch?v=RGLoA0hP2jY

There is a change to the technique shown here, though. When the tissue gets damp it expands.  Now after I have laid the dry tissue onto the carbon mat I damp it slightly so it expands and then very gently pull the wrinkles out.

Please be aware that PVA can stop the carbon from bonding, so it may weaken your product slightly.  I have never had any problems, myself.