airnocker, i took your suggestion and made a pop bottle skirt. my design turns out to create a real tornado, so strong that even the fairly stiff pop bottle fringe gets sucked in a bit. i decided that the vacuum hose was too far from the spindle and ran the boot thru the band saw to shorten it. so much for all the fancy fusion360 lofting. the two parts now match within a 1/4"! i will change my 3D model for the next prototype.
i may make the next dust boot using a plug rather than a mold. i realize that building from layers of fiberglass, while quite strong, lack a lot of detail, and that sharp edges are impossible without vacuum bagging. i will need some foam that can be easily melted. i know styrofoam melts with gasoline, but it really lacks the ability to carve any detail being so "beady". anyone have suggestions? i suppose too, i could cut half pieces and then turn them over and mill the backsides. i did this once for a big wooden spoon. the question would be what material to carve for this project?
i like carving mold pieces from rigid pink foam. has anyone experimented with making molds, both the female and male, and then coating the female mold and using the male to force the mold material around in a uniform thickness, like injection molding but without the pressure, and then clamp them together until the material sets up? there are several additives for fiberglass resin that might work which make the resin thick like toothpaste. this part needn't be perfect or gorgeous, just robust.
anyway, my turbo design appears to have great potential. when milling with an 1/8" bit it is difficult to remove the wood chips. this design puts all the vacuum right over the cutter, not offset by inches sucking thru bristles. i will continue to try different ideas.
