Quote:
Originally posted by Cathar
I investigated sand-casting. The channels are too fine for anything other than a one-off cast as the fins of the mould would snap as they are too deep. At least this is what about 20 different sand-casting places told me before I got the hint...
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That's because the heavy texture of the sand, And copper can't be casted in plaster. It's melting point is over the point of calcination, where the chemical bond between plaster and water is broken. The water will be released, and the cast become soft powder. This process also absorbs a lot of energy, that's why plaster is used as fire retardant in steel buildings.