terracotta moulds for casting the CuAs ingots
…breakage during casting
Over the last weekend, I burnt the clay moulds and tested them with CuPb and CuSn last Monday. Unfortunately they broke during casting. So this means back to the start, and redo the moulds – this time with tempered clay and some hay, which makes the mould also much closer to the ones we know from the Bronze Age!
The sandstone moulds are in preparation as well; I also started with the first sand casts – more soon!
That’s disappointing. Do you have any ideas on what caused them to break? What temperature was the liquid metal during the cast?
Eager to see the rest of the moulds!
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Yes, the reason was a combination of mould material (not tempered, no organic) and metal pressure on the moulds. The metal was cast with 1110°C. I have to redo all moulds with different, freshly ordered clay, so it will take a while!
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