I got the casting metal today. I can't wait to try this. I plan on casting a stereotype:
Stereotype (printing - Wikipedia)
It will be of the TeX logo (see photo). I need to adjust the positions of the letters.
As it turns out, you can use plaster molds to cast type metal, however, they say that the mold is destroyed when removing the cast. I don't know if this would be true for only 3 display-size letters. However, to be on the safe side, I will make a reversed positive plaster mold, like the final metal cast, so I can cast as many non-reversed negative plaster molds from it, which I can use for making the final casts. This means I also have to start from a non-reversed negative wax model.
The procedure with papier-mâché involves making multiple layers and gluing them together and beating the resulting "flong" into the mold, which in this case is a frame of handset type. This doesn't sound practical and wax probably wouldn't stand up to having something beaten into it.