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1. Cut out materials for the layup.
   1. Breather, peel ply, and vacuum bag, mylar.
      1. Breather should be smaller than the peel ply so it does not get in contact with the epoxy at any point, or it will give your part a fluffy cotton beard once cured.
      2. Cut these out to fit loosely in the mold and around your part. 
      3. If unsure, cut larger pieces. It's easier to trim them down to size during the layup than it is to cut entirely new pieces during the layup.
      4. The mylar should be cut out precisely to the shape of the piece as possible. Mylar gives things a nice surface finish.
         1. Surface prep the mylar!
            1. Wipe it down with IPA or ethanol, then give it several coats of Frekote (770 Release Agent).
2. Cut out the composite fabric for the layup.
   1. Lay out the fabric neatly on a table, make sure it's straight and flat.
   2. Cut out a sheet of wax paper to the size you want the fabric to be. If you want to end up with a strip of fiberglass that's 10"x5", cut out wax paper that's 10"x5". 
   3. Spray the wax paper with 77 (a light spray adhesive)
      1. You'll need some extra hands here: two people hold the wax paper horizontal in the air. You spray a light layer of 77 over the wax paper, and the two people holding the wax paper swoosh the paper upwards into the cloud of 77. 
      2. Try not to spray 77 on people or important stuff. It sucks.
   4. Put the wax paper on the fabric you laid out, sticky side down. 
      1. Smooth out the wax paper, gently sticking it to the fabric. Be careful not to put wrinkles into the wax paper, but it doesn't have to be perfect.
   5. Once stuck, cut the fabric with the wax paper backing out of the larger roll of fabric.
      1. You should have the nice piece of fabric that you wanted with a nice wax paper backing on it.
   6. Note: The wax paper backing serves several purposes. It makes it easy to work with the fabric composite (move it, carry it, etc.) without disrupting the fibers. It also makes it easy to wet the fabric with epoxy (you can tell when it is wet, without over-wetting it). If you overwet the fabric, it will make your part much heavier.
3. Prep the mold.
   1. Yup, back to this guy.
   2. Clean the mold
      1. Wipe off the mold with IPA or ethanol. If there's dried epoxy on the mold from a previous layup, scrape it off.
   3. Wax the mold.
      1. put a light layer of wax on the mold, then buff it out until the mold is shiny.
      2. wait for the mold to dry.
      3. Note: Waxing the mold serves as both a nice surface finish and a mold release agent.
   4. Vaseline the mold.
      1. put a light layer of vaseline on the mold.
      2. Note: Vaseline-ing the mold serves as both a nice surface finish and a mold release agent.

Do the Layup

Using this process, you do NOT need to do the layup prep and the layup itself on the same day! That's nice if you have really busy people that can't dedicate a solid 7 hr block to a layup.

1. Make sure all your stuff is ready to go. Lay it out neatly on tables so it's easy to work with. Put a layer of painter's plastic over the table so you don't destroy it with epoxy.
2. Wet the fabric with epoxy.
   1. This is where the backing comes into play. To check if the fibers are appropriately wet, check the backside and look on the wax paper. If the wax paper looks wet, you're good to go. If it's dry, add more epoxy.
   2. Once wet, blot the fabric with a paper towel to remove excess epoxy (and weight!)
3. Put the fabric into the mold. 
   1. This process will depend a lot on your part and it's geometry.
   2. Take your time, make sure things are smooth and pretty and there aren't bubbles in the fabric.
4. Bag the layup.
   1. Put peel ply over everything that has epoxy on it.
      1. Peel ply helps you remove the breather, so it doesn't stick to your layup like a beard of cotton.
   2. Put breather over the peel ply.
      1. Don't let the breather touch epoxy. Trust me on this one.
      2. Breather is important because it helps "distribute the vacuum" over the whole layup. Without breather, the vacuum tube would only suck down in one spot of the vacuum bag, and that would be sad. Breather helps distribute that pressure evenly over the layup.