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- We glued together 4 sheets of 1" MDF from Boulter Plywood with Titebond II; we intentionally made the bottom sheet slightly wider than the rest to create a ledge for handling and for fixturing to the router.
- We cut the mold on a CNC router. We screwed the bottom ledge to the router table, and then started by drilling several holes for alignment pins. Then, we cut slots to allow the molds halves to be pried apart easily. Then, we did a rough pass of the shape with a 0.5" straight router bit. Finally, we did a finish pass of the shape with a 0.5" round endmill, using the constant scallop feature of MasterCAM.
- We coated the mold in polyester gelcoat, and sanded down that surface until relatively smooth.
- We accidentally cut the coupler section of the mold too large, so we glued on a sheet of thick mylar to make the part smaller. The mylar was just glued on with 3M super 77, and released the part cleanly later on. If possible, we might want to do this on purpose next time.
- We bolted the coupler section onto the nosecone section, and used wooden alignment pins to keep the mold parts correctly positioned.
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