I bought the Model Maker kit several years ago, and have only
tried the metal-backed material. I made a very detailed design
on the computer, printed it out on a transparence, and placed it
over the material. After it is “cooked” under the lights, you
have to scrib it very gently, but continuously under running
water for about 20 minutes. I then had a rubber old made from
it. The piece was 1x2" and in sterling it weighed nearly an
once! Needless to say, that wasn’t exactly a commercial
success, so I’d recommend filing or grinding most of the metal
off the back before molding, or using one of the green sheets,
burn it out and cast it, and go from there. It did, however, give
me the most incredible, accurate details possible for a minimum
amount of work! I tried it with a “positive” and with a
"negative" design, (can be done at Kinkos) and the one with the
details “dug out” is far clearer than it the details were the
raised elements. I then applied a patina, and it has stood up
very well over the years, as the crevices are so deep.
Hope this helps.
Ruth