I mentioned in the moldmaking post that I normally make a rubber insert for my medallion molds so I don't have to fill the cavity with clay. My new batch of rubber reached room temperature last night, so I poured one for the new plaque. [As a side note, you don't want to overlook the "room temperature" part of room temperature vulcanizing (RTV) rubber. Trust me.]
Here is the insert. I'm not especially careful about bubbles when I pour these, since all I need them to do is fill the cavity.
It's kind of fun to see him semi-transparent. They remind me a bit of the beeswax ornaments I saw on a visit the Plimouth Plantation. Too bad rubber doesn't smell like the beeswax!
This is the mold with the insert. All that's left is to box the mold and pour the lid. As you can see, the inserts leave the mold much cleaner than the clay. But mostly they just enable you to make multiple molds more efficiently.