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Requires a foam plug
Creating the plug entails the same process as a full foam mold, so going straight to the foam mold might be time efficient
Ways to make the foam mold include:
https://www.youtube.com/watch?v=MAinuf5I_dw (foam glue together, cut, sand, apply fiber glass, sand, apply putty/plaster, sand, primer, apply mold release PVA and wax work well)
Adding fiber glass onto the foam molds might be a good way to improve the surface finish and make the mold less leaky (plus we have a lot of fiberglass).
Pros:
potentially less sanding (less time maybe)
mold is reusable
better surface finish than just a foam plug
Cons:
more material
more expensive
will still require sanding the foam
more time (maybe)
Aluminum
Process
Pros
Cons
3D printing
https://www.youtube.com/watch?v=4ND2WtEZatY
Thermoforming Molds:
https://www.empirewest.com/thermoforming-mold-design-and-materials.html
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