(WIP) Hand / Wet Layups From a Foam Mold

Step-by-step guide

Preparation

Figure out materials
1. Reinforcement
  1. For S22-S24 we used foam molds to make a fiberglass tool.
  2. Reinforcement needs to be precut beforehand to the right size
2. Resin
  1. Pot life determines how long you have to work with the resin in a pot/bucket before it starts to cure. Higher pot life gives more leniency
Sanding: We want the mold to be as smooth as possible. Sanding gives a clean finish that's close to the CAD and makes it easier to demold
1. Spackling
Apply Joint Compound:
1. This needs to be lathered all over the mold in 3 layers. Miss no spots
Apply Primer: this seals the mold
1. Use paint rollers; this will give an even coat of primer
Apply mold release
1. In the past we have used PVA. Historically this has rarely worked on a foam mold.
Gather consumables
1. Gloves: protection from resin
2. Disposable aprons: protection from resin
3. Stir sticks
4. Paint brushes: used to apply resin
  1. Cheap and disposable. Don't reuse these
5. Buckets: to hold the resin
6. Scales: to measure the resin
Know who is coming to help
1. Make sure they have the required PPE (respirators)
2. Assign them roles
  1. Resin mixers
  2. Resin appliers
  3. Fabric appliers
  4. Overseers

Conducting the layup

Ensure everyone is wearing PPE correctly
1. Check respirators to make sure there is no leakage
Mix resin and hardener together according to the ratios given on the SDS or on the packaging
Apply resin with paint brushes in thin coats that are the size of the first piece of cut reinforcement
Tack down the reinforcement
Add the resin necessary to saturate the reinforcement
Use scrapers to scrape excess resin out of the reinforcement
Move around the mold and repeat steps 2-6
Apply peel ply
Apply breather
Apply vacuum bag

Common issues