Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

  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. As applicable, put the mylar (Frekote side DOWN) onto your composite. Smooth it out nicely to give your part a gorgeous surface finish. 
      1. Only put mylar where you want the layup to be smooth and it's not already touching the mold.
    2. Put peel ply over the mylar on 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.
    3. 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.
    4. Line the mold with vacuum tape, and put the vacuum bag over the mold.
      1. first, wipe off the mold with IPA where the tape is going so the tape can stick to a clean surface.
      2. Tack the corners of the bag down first, then slowly seal the rest of the edges. It's important to make sure that all the edges are sealed or the vacuum pump won't actually pull a vacuum.
      3. Do not, I repeat, do not get epoxy on the vacuum tape. It will never stick. Never. 
      4. Make sure to leave room for the vacuum hose.
    5. Seal everything up, check it, then check it again.
    6. Turn on the pump!
      1. watch with satisfaction as the vacuum bag sucks down around your beautiful composite part.
  5. Let it cure. 
    1. Patience, young padawan.
  6. Unbag it! 
    1. Careful not to stab yourself on sharp composite edges.
    2. Spend an appropriate amount of time admiring your layup, then sand it and finish it if needed.