Hi all,

I have a few questions about making flat carbon fiber sheets and hollow rectangular box channel.

When making a flat sheet under a vacuum, (or anything for that matter), what kind of release film should I use? From what I have read, Peel-Ply and Porous release films will allow excess resin to be pulled from the layup, but a non porous release film doesn't? But parts created with the non porous release requires less finishing, is that correct?

Second, I'm looking to make a box channel by wrapping a piece of Styrofoam with carbon fiber, then remove the stryofoam with acetone. I've already created a piece like this, but since I don't have vacuum equipment (yet) the finished part was rounded and not square like the stryofoam. I assume creating the part with a vacuum will make the carbon fiber conform to the square shape better.

I'm working on really small parts here, The box channel is made using a piece of 1/4" x 5/8" stryofoam and I wrapped it with 5 layers of 5.7 oz/sq yd .012 thick fabric. I was aiming for the side walls to be 1/16" thick. Would a thinner fabric and more layers work better to create a square part, or thicker & less layers?

Thanks for any help,
Randy
 

With Styrofoam you have to be careful because the foam will crush with too much vacuum. For something that small with that many layers you will probably want to get some aluminum to use as a mandrel so you can give it as much vacuum as possible. Also maybe look at braided sleeve as wrapping cloth around square mandrels can be hard. Just make sure you release it super well, getting the part off can be difficult. Some times it helps to leave part of the mandrel sticking out one end and laminate off the other end so that you have two places you can attach things to to assist in pulling the part off the mandrel