I cast my two copies of Andromeda Ascendant today.
This was an experiment to see how well the ABS material burned out. I couldn’t be sure that some ash might be left in the model. So, to make sure that the molten metal would flow, I thought to cast these with a 482 C final flask temperature. The spaceship has rather thin swooping rails on each side and a hotter flask means the metal has a little bit more time to flow inside the rails before it freezes solid. On the other hand, a hotter flask slows the surface freezing of large and thick areas like the spaceship body and increases the risk that the casting will show catastrophic shrinkage faults or cracks or holes.
I was able to fit both models into a 4×6 inch flask. I chose to cast them in my white bronze alloy so that they could be polished and show as silver colored spaceships.
The casting was successful, but I did see shrinkage flaws on the main spaceship body. Knowing this, if I was to cast these again I would reduce the final flask temperature or use a different bronze where I have had better success controlling shrinkage.
The ABS burned out quite successfully. I held the flasks in my kiln for 5 hours at 732 C overnight to try to ensure complete elimination.
The pictures below show the models sprued and ready for casting, and the actual cast result. The ships have been separated after casting and roughly finished but they each require fine finishing and polishing.