View Full Version : Two Part Mold From Soft Clay

08-15-2009, 11:16 AM
Okay, hello everyone!
I've been doing lots and lots of research on resin casting and prop making over the last day (didn't go to sleep last night I was so engrossed). But a problem I've encountered:

I decided to get the hang of casting and what not, that I would start off by trying to cast a sword hilt I'll be working on for a future costume. I know that probably seems complicated, but I'm okay with that, I'm up for a challenge. From what I've gathered people don't often bake their sculpts before trying to make the negative, I feel like that would not be a huge issue if a two part mold wasn't necessary. I've Googled the bajesus out of two part molds but can't seem to come to a definitive answer. Does spraying the still soft sculpt (4 s's, fancy) with a Kryon clear coat reinforce it enough to not be ruined when trying to press it into the first half of a two part mold? I'm not sure if that question is easily understandable, so if anyone needs clarification, please ask. Actually, if anyone could just let me know the best method of creating a two part mold from a sculpt, preferably a mold of some sort of plaster, that would be great! Thanks in advance guys!

Edit: I do know that I'll probably ruin the sculpt in the mold making process anyway, I just want it to actually survive that process. Just making sure that's clear

08-15-2009, 01:49 PM
for the resin casting, it would be good to do one of two things, use a hard model if you plan on pressing it in, or gently build up to make the sides and not PRESS it in. (i will show a video that will show how)

for plaster casting (which is what i like to do) here is a great video that shows you all the process to doing a 2 part plaster mold, and in the video will show you how to build up the sides so you dont have to press it into clay)

its a 3 part video and is the exact method I learned in school (went to school to learn movie props and such)

08-15-2009, 02:59 PM
AHA! Thanks very much, that video will be helping me out quite a bit. Also, somewhat off topic, but where did you go to school for that? Was it like a film school? I ask because I will be starting college shortly and have been interested in getting a glimpse at this kind of thing, but don't really know what to be looking for.

08-15-2009, 03:37 PM
I'd be careful if I were you; casting resin can be very dangerous. It can cause all sorts of lung problems and problems with the reproductive system. I was going to cast something out of resin, but once I found out how toxic it was, I decided it would be better to use hot glue instead. I would strongly advise against using resin, but if you decide that you must, do it outside, set up some fans, and maybe wear a medical mask. But if I were you, I wouldn't use the resin! Use hot glue instead.

08-15-2009, 09:33 PM
I went to the art institute of Pittsburgh, for the major, entertainment design, it was really fun and was all about making movie effects and props and masks and such. the one in Pittsburgh is the only one that has it, its a bachelors of science, so you have to take your math and English and stuff still. i don't think they have the major on the website, you'd have to look for industrial design, its under that.

08-15-2009, 09:40 PM
I'm not sure if plaster is the best thing to use for overly large props, because while it is strong it is also super heavey. Also take note that if your sword is super detailed plaster does take better details than any other type of casting mold.