We want to make a split mould from a cedar strip canoe, but I was wondering what the best material is to do this job. I know that the most use poleyster/CSM but I saw also molds made from epoxy/fiberglass. In epoxy/fiberglass I guess you have a lighter mould, but how how many layers do you need to make them stiff enough with fiberglass? Is a tooling gelcoat necessary or can I start with epoxy on the waxed plug?  What are the advantages/disadvantages of both systems?