: HI, I use to do some of this type work at Fisher Body and other places, all
: before CAD-CAMs. The base construction was somewhat similar to Kayak
: building except it was much more solid. The work was done on very large
: and very accurate surface plates using height guages as the main measuring
: tool with tolerances +/- .001. We used mahogany glued up in thin layers
: usually running across the whole pattern, on say a quater panel. But large
: pieces were built around a solid frame to eliminate weight. Later we used
: a special wood that was prelaminated in 1/16 inch layers to help eliminate
: expansion or shrinkage, and finally a plastic called Ren Shape that was
: worked and machined like wood. But I think strip building a pattern plug
: would work OK as long as you aren't too worried about accracy. You might
: want to contact a pattern supplier, like Ren Plastics or Meyer for some
: supplies and idea papers. I have seen Meyer on the net but not Ren. One
: thing I would definitly get is parting paint. It is water soluble and use
: to be green. I have seen it save many pattern from destruction from
: sticking. We shellac the wood first until shiny. Then put on the green
: parting by brush or spray and let dry between coats. Then brushed on three
: coats of Tree Wax and shine each coat and finally put on a mold spray
: parting. Then we brushed on a (Surface Coat) of epoxy and after the
: brushing we poured the rest of the mix over it in a thin layer. Don't let
: the excess flow into pockets or it will have excessive heat and bubble or
: warp. Right away we dipped our brush in alchol and flipped it on the
: surface coat, which brings up the bubbles to the surface. Then let it set
: up to the point where you could dent it with you fingernail (this makes
: the coats adhear better at this stage while most of the heat has
: dissipated) and pour on a second (Surface Coat). Again, when you can dent
: the epoxy with your fingernail, put on a coat of (Laminating Coat mix)
: epoxy and start laying your cloth and brushing in laminating mix into each
: layer. Hope this helps in some way.

: John

Me again--John,

After your lamininating is finished and set up, cut plywood boards reinforcing ribs to roughly fit to the shape of your contured lamination through the centers and around the edges. With fiberglass fluff you can buy from a pattern supplier, mix this with the thinner (laminating epoxy)into a stiff cottage cheese mixture and putty the edges and squish it onto your lamination fiberglass. Then using you round nosed putty knife radius the cottage cheese around all of the ribs. This will give you a strong stable mold to laminate you car body section from. When prepairing this mold section for your final car peices, just brush on you green parting two or three times, or spray, then use the Tree Wax and spray parting. When you seperate your part from your mold the green parting will wash right off with water.

John