So I had a problem. I needed to cast this in a 2 part mold, but I wouldn't have been able to clean the clay off it (I tried). So I used small baked clay balls to suspend the object above the floor of the mold. For keyholes I did this, but next time I will just erect pens of something. That will be more efficient as this was quite a mess. Poured the first half: So far, so good. Built up the mold wall: But oops, I screwed up! Once I poured my second half, I realized that I forgot to spray mold release! I tried to remove the freshly poured silicone, but to no avail. I poured it back on top. I had to use a cutter to separate the two halves, so this really sucked. Then I cut out an air vent, sprayed release and closed the mold with cardboard and rubber bands. I looked for my air vent, but couldn't find it. I measured how much resin I would need by placing the object in water and then measuring the amount of water displaced. I used exactly that amount. But once I poured the resin, I realized mistake number 2! I stupidly had the air vent pointing down, not up! Resin started linking out! I plugged the hole, but lost a good deal of resin. So here it is, the clayless 2 part mold. Besides the 2 screw-ups, the idea of making a mold without clay worked pretty well. I don't like how messy it gets and how it sticks to objects.