Composites/Adhesives Knowledge - Dump

Owned by Nicole Choe
Last updated: Aug 20, 2024
2 min read

For future battery-enclosure panels:

  1. It is better to infuse against gravity

    • Reduces risk for dry-spots - the resin cannot just flow in-accordance to gravity

  2. Depends on the scale of the part
    Perforate your core with 1/8” holes spaced around an inch apart

    • Helps the resin flow-through adequately through both-sides

    • Can use school’s CNC machine to program and cut-holes

  3. Always perform a vacuum-drop test before starting infusions - no drop in 15 minutes

  4. Use breather if-possible to prevent the bag from being punctured

  5. Always add lots of pleats (6” long) to your bag so that every-crevice is covered well with the tape

    • including at the tubing where the Enka sits

  6. Instead of wrapping the chromate tape around the tubing, stuff the chromate inside, poke a small-hole for the resin to go-through

  7. Use rollers to help seal the chromate together (VERY important the seal is perfect)

  8. Add 0.5-0.75” foam to necessary places in Aero-body where there will be cut-outs during infusion - helps keep the structure together

Calculations for resin:

  • General rule is to give core a buffer of 10%, and for all-else a buffer of 10%

  • Good to perform a gel-test with a small amount of resin to see how fast gelling occurs - record initial temperature, amount of time which has passed and amount of catalyst-used. Can also sometimes get away with a lot less catalyst than you think - consider adding less than the spec and performing hardness tests to make sure samples are still viable

 

Adhesive Knowledge-dump:

  • Abrase surfaces with 80-120 grit sandpaper to areas

  • Mix and bond materials together

  • Consider creating tooling to help bond-things together

 

Screws Knowledge-dump:

  • consider adding torque strips - that way when screws come-loose it visibly shows up on-the-part

Male versus Female Mold:

  • Male molds are better for when you want the out-side of your part to look nice, for example for the aero you want the outside of the car to be the “A” side to decrease drag so you use a female-mold