On Mon, 08 Mar 2004 03:53:56 GMT, Scott Gettings
wrote:

:
:In my experience, the mold transfers everything to the product. So your
:initial plug has to be basically perfect, although you can remove a few tiny
:"high" spots in your mold that were low spots in the plug.

I agree, but even with a perfect mold, (using epoxy, wet layup and
vacuum) unless I had a primer of some kind before the cloth went down,
I'd end up with pinholes between the fiber bundles. Think of a tick
tack toe grid, with the outside rows representing fibers. There would
be a pinhole in the center square. It happened even when I tried a
layup on a piece of plate glass.

:A good, hard
:molding gel coat helps a lot.

Absolutely. And as good a plug as you can create, to take the mold
off of. We used epoxy gel coat only.

:You need to be at 2000 grit and buffed out to
:be really smooth. I can't comment on nickel plating a mold, but you can get
:very, very smooth with molding gel coats on complex surfaces. For flat
:surfaces, or 2-D curves there are many more options.
:
:Using wax then PVA release agent will usually transfer some surface
:imperfections to a product. After a few releases, you should be able to use
:mold release wax alone. A few good coats of wax properly applied will transfer
:negligible imperfections to the product. Nothing that can't be buffed out --
:as long as your resin is very hard and cured. Soft materials don't buff to a
:high gloss nearly as well.

I ended up using Frekote A-700NC, it's silicone based, non
transfering. Very good stuff.