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RTV molds from TAP Plastics

Hi Mona Great description of The Crucible…makes me wish I lived on
the Left Coast. Oh well…

I had a question about the RTV molds from TAP Plastics you
mentioned. Would you share info on this subject, please? I do use
Bellicold and I do like it, but your statement about tossing it out
piqued my interest. Could you be specific about the process and
about why you prefer it to Bellicold (or any two-part silicone mold

'Preciate your input,
Linda Kaye-Moses

Hi Linda- I took your class a while ago and you used a two part
molding product - blue gunk + pink gunk = lovely purple flexible
mold I use all the time. Is this bellicold? I would love to get my
hand on some more of that wonderful molding stuff.

Thanks, Lilly


I used up half a new supply of Bellicold ($15!!) trying to make
molds of some ancient coin reproductions that didn’t distort the
faces. Each time I pushed the coin into the Bellicold the face in
profile ended up distorted. I have used Bellicold in the past to mold
other things for PMC and haven’t had this problem.

On the advice of the science fiction costumers I met at the
Crucible, I bought a jar of the TAP Silicone RTV system (jar of white
goo that they call “Side A”) and a small jar of TAP Silicone RTV
Catalyst (Blue, Fastcure). Their product bulletin 7B explains how to
use them. I didn’t buy a vacuum pump for the air bubbles, just used
the drip-from-a-shelf-using-a-Dixie-cup method the handout describes,
and it worked well. I put a block of Sculpey in one of TAP’s little
molding containers and pressed the back of the coin into it. The
Sculpey took up room so I didn’t waste molding material and also kept
the molding material from flowing around the back of the coin. The
Sculpey also can serve as a base if you are molding an antique
pin…the pin sticks down into the sculpey and the pin itself isn’t
harmed. The Sculpey allows you to make a one-sided mold of just
about anything, although RTV is designed to mold an entire 3-D

Because the RTV molding material was liquid and dripped onto the
coin, rather than being a cohesive lump like Bellicold, I didn’t get
the same sort of distortion I did with Bellicold. Rather than my
shoving the coin into the molding material and displacing it, it
dripped around and conformed itself to the object, hence the great


Hi Lilly Cohen,

Bellicold can be purchased from Rio Grande and a similar product
from MicroMark. There are other suppliers out there, too. Happy to
hear from you.

Linda Kaye-Moses