Hi Daniel. There was something on this subject some time ago and I
must have been too busy to inquire then, but what, exactly are the
symptoms of the problems you have ? I have been casting carving wax
for a very long time, far more than injection wax, and most of my
students use it as well. There have never been any problems that I
could possibly identify as having to do with expansion of that wax.
Our flasks follow an automatic kiln setter program at school and a
recommended one for Satin Cast 20 in my own shop. I do mix
investment by eye to a great extent, making it a bit thicker or
thinner depending on the models needs. No problems at all. Have
honestly, in over 20 years, never lost a flask. So this must not be
something specific to carving wax, but some other reason you are
thinking expansion damage. Now I'm curious. As well as very happy
we're doing something right.