The goldmsith I work for part-time is having a heck of a time
casting lately. Major, abnormal porosity that he couldn’t figure out
and he’ve done a lot of casting. New equipment earlier this year,
and already the rubber gasket and seal on his vacuum casting machine
is dry and brittle. Upon doing some research, he’s been casting too
hot. His flacks were at 1150-1200 degrees for yellow gold, a bit
lower for white. Now he istrying at 900 degrees for the flask temp
for 14kt yellow casting. I haven’t heard how it went.
Any of you ever had problems with too hot flasks, too short burnout
cycles and abnormal porosity? He’s rethinking the burnout cycle, the
flasktemp and even the metal temp.
I don’t cast, I just clean up the castings. I’m not into casting but
will do it when necessary.