Use an exiting bass guitar (an old one) and pre pare it to make polyester moulds from each side. See all the videos.
Make each guitar part using the vacuum infusion process and join these together, See the videos.
Watch more videos.

There are many ways to use the materials but a bass guitar body is a reasonably open and simple shape. For me using the infusion process will give the best cosmetic result although learning the infusion process is quite a challenge in itself. It could mean a couple of throw away parts but that's normal too for someone starting out.

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