resin detail

[jm]

Pop,

I just use it clear, but color is no problem. Get it here.

http://www.shopmaninc.com/pigments.html

Bass1cpr,

Are you making pop molds from an epoxy master?

You got me to thinkin',

1. A hard master can't deal with any sort of undercut, and something like a zipper would be impossible.

2. Plastisol shrinks, and it takes up some of the styrene solvent from polyester resin, thus about a 10 mold life and some variability. You can plan to lose 3-5% of size with it if you are making polyester molds.

3. Polyurethanes are about as expensive as 2 part epoxy. Epoxy shrinkage is nil, and polyurethanes shrink less than 1%. I'm experimenting with polyurethane for master molds. Hot plastisol seems to hurt them, but I may be able to add some aluminum or ceramic filler to solve that problem. I use Easyflo 60 for very quick hard masters to get a few negatives, or to use as a core for a 2 part mold. De-mold in less than an hour is great when I'm having a (rare) creative moment.

One thing about the fast urethanes. You have to have all your ducks lined up, and execute your plan like clockwork. You only have a few seconds between "properly mixed" and "it better be in the mold". Also it pours like water, so the mold better be watertight.

Here's a great source for mold making urethanes. Also sculpting clay and mold release agents.

http://www.shopmaninc.com/moldmaking.html

Another neat trick I'm working with is using casting wax to make masters. For instance, you could pour a reaper, then trim the tail down to a rat tail, add a little wax to the body with a brush, shape it into a minnow.

A hard wax will take a smooth polish, and it naturally releases from almost any molding compound. If you want a hard master, you could make it out of epoxy, and even if there are undercuts, just melt the wax out.