Ok....so I have been thinking about making my own plastics for some time now...but have not started...i have been searching the forums but cant seem to find the answer i am looking for..first off..what is rtv (cant search for it because it is only 3 letters)...and are there any instructables on making a home made mold out of plaster of paris or something better?...i am at point a in the process, and i think the first thing to do is to learn to make molds...buying some would be cool too, but i have some ideas and want to try some stuff out..that leads me into my next question...best way to design a mold...would you guys suggest modeling clay as the best material to use?...i know i can do some google searches too, and will, but i figure i might as well ask some people who have tried this before...i know this website has been around for awhile, so im sure this question has come up numerous times, i just cant seem to find it...any info would be great (links or personal experience)...i do appreciate the help, and do plan on following through on this hobby...thank you very much...