I made another attampt last night [Jan 13] at an even higher temperature and the results were even worse, it appears that as the tempperture of the metal increases the amount of gas in the spew increase, which results in "pinching off" the flow of the metal, casing the metal in the spew to break up into small packets some of which are just little balls, which solidify and completly clogg the spew.
The solution might be to increase the size of the shims that are between the two plaster of paris "containment molds" so the there is less pressure on the two halves of the RTV mold, thus maybe allowing some air to escape from the spew.
The is about the 5th attempt to cast a compete leaf,
The pewter in the input spew hardens and stop flowing
even tought the metal is "extra hot". And there some
hissing and gas and smoke comming out which there
shouldn't be after five shots. But this is par for the course,
metal casting can be an obstinent creature.
These are fantastic. Great to able to see the care you take. The angles!
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