So over the last couple of days I have been working on making my own molds. I started small with a 3oz jig. The first attempt was with Bondo (the mold on the right) the mold came out great, but the plug was destroyed removing it from the mold. The first pour was perfect besides the fact the holes had to be drilled out a little. The second pour the mold popped there was an air bubble just under the surface this pretty much ruined it. So I decided to go a different route and make a mold out of Durams water putty but used the jig from the first pour for a plug. After a day of drying I did some minor clean up and baked it at 400F for an hour. Then did a pour it came out okay, not nearly as clean as the first one, but I think that is just a copy of a copy thing after the second pour the mold developed a crack, I think this was from me tapping it against the table to get the jig out. So I patched the thing back together with more water putty. Here is a pic of everything the two powder coated ones are from the water putty the other is from the bondo. The bondo left a much smother finish but that did not seem to matter after powder coat. Any suggestions on mold making material? The whole thing of bondo is $12 and the water putty $8 and there is enough to make 15 to 20 molds like this one. I was thinking of spraying the water putty mold with some 1200f header paint to smooth it out and maybe hold it together better.