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- Wet sand mold to 2000 grit using sanding block (made of foam)
- Wax mold (3 layers of Mold Release Wax, yellow container)
- Apply PVA film with fine-haired brush, let set for 20 minutes
- Mix cabosil + epoxy and apply to mold (thick on edges)
- Layup- don't wet plies before laying down
- Tab at least 1" at base, shorter at tip
- Attach halves of mold carefully, making sure tab doesn't get stuck
- Vacuum bag
- Cut bag in cone shape
- Press vacuum bag firmly on edges to make sure there are no gaps, as this will cause bubbles later
- Use "spear tool" (long, thin rod) to push vacuum bag through mold
- Mold release: use chiseled popsicle sticks and hammer (add more until pops open)
- Apply ablative (using layup jig)
- Use heat gun to dry (don't overwork)
- Oven cure
- Sand outside
- Sand inside (seam)
- Plane ends
- Fill low spots with ablative + epoxy mixture
- Sand with 60 grit to roughen up because epoxy doesn't stick well to itself
- Paint
Lessons Learned:
- Don't coat the mold multiple times with epoxy - just once, let soak and WIPE, then cure and sand
- Protect edges with aluminum or something rigid and straight to prevent them from getting rounded
- Do not wipe mold with acetone once PVA film has been applied or it will come off
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