Follow up on my investment problem.
I store all my investment inside the house. My inside house
temperature is set at 72 degrees. The investment never sees the heat
of the day until I take it outside and start my mix. It has no time
to get hot. I use purified water stored inside my house. Again it
does not see the heat of the day until I mix it. Neither investment
or water is allowed to sit outside before mixing it. They do not have
a chance to heat up from the outside ambient temperature any more
than a degree or two before the mix is vacuumed and poured.
I quench in several 30 pound kitty litter plastic containers. When
one gets warm I move on to the next. I fill each one just before
quenching. That provides ground water temperature not heat of the day
temperature to the water. The temperature of the water from the
outside hose is 84 degrees.
I have cast in the summer for at least 30 years and have never had
this problem before. One day I cast when the registered temperature
was 122 degrees. My casting area temperature was around 128 degrees.
The only affect the temperature has is on the filled flasks. They dry
out faster so I place them in the burn out oven a little sooner that
I would if it was winter.
I try to complete my investment cycle in 7 minutes. I mix for 1.5
minutes with an electric mixer at high speed. I vacuum for one
minute after the investment pancakes. I vacuum the flask for one
minute after the first bubble appears. I can invest two sets of
flasks in the 7 minutes I allow my self. I pour the investment
through a kitchen strainer. That procedure has work for me for 30
Oh well I won't be casting for a while. Its time to grind, solder
and finish stuff. I have four big pots to inlay stone in and finish.
Thanks for the comments.