It is easy to pull individual strands of carbon fiber while cutting. Here is an easy fix that will help keep your carbon fiber strait and without annoying pulls in the cloth. This tip will help the finished job look cleaner and more professional.
Below is an example of a carbon twill. The material has been rolled out flat, on a clean table. You will find that the cloth can twist. Try to make the cloth square before cutting. Use a corner of a table or a builders square as a guide.
Lay out your rectangle. I have pre-cut my peel-ply to the length and width of the decks shape. This works well as a guide for cutting the carbon. Make sure your cut piece is larger by a couple of inches than what you are laminating it to.
Apply masking tape to the areas where you want to cut the carbon. The cloth in the photo below has sewn kevlar on the outside edge. No need to tape over this.
Once taped it should look like this.
Using a long strait edge and a very sharp utility knife. Cut along the middle of the tape. Make sure you cut all the way through the tape and cloth.
Once cut the remaining tape holds the carbon cloth from twisting and prevents pulls in the material. Do not remove the tape while laminating.