Carving wax vs. injection wax?

Question for you wax carvers,

As a caster (or supplier to casters) we see problems with carving
wax expanding enough to damage itself and the investment surfaces
before melting or burning out. I suggest RTV molds so we can cast
with injection wax.

Are there other ways of dealing with the oddities of carving wax
compared to injection wax?

Daniel Ballard

  Are there other ways of dealing with the oddities of carving wax
compared to injection wax? 

Use a water to powder ration a little on the thicker (less water )
side of the allowable range. While this produces a slightly less
porous investment mix, it’s stronger too, less easily damaged.
Then, let the mixed investment set up longer than you might
ordinarily do, before putting it in the burnout oven. And be sure
your burnout cycle includes a decent soak at around 300 degrees,
before going higher. This will let more of the viscous carving wax
run out before it starts to actually burn off.


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.