A simple method for making a one-off FG fuse is to carve it out of dense blue foam, sand it smooth, and lay up glass cloth on it as smoothly as possible. When hard, cut a hole somewhere- wing saddle is good, and slowly pour laquer thinner into it. The thinner will dissolve the foam (test first). The fuse will be a little rough, so coat it with lightweight spackling and sand smooth. Coat with sanding sealer, sand and paint it. Don't breathe the fumes!