From you bit of description of the situation, I would think that the
company has made molds using some sort of heat vulcanizing mold
rubber, in that every wax has release powder. Silicon RTV molds are
GREAT in that they make a perfect replication of the master and
usually no release is ever needed, save “making” an air release.
Heat vulcanized molds, especially rubber verses silicon, HAVE TO BE
release nearly every injection, at lease in my limited experience.
Silicon molds, have a shorter life and are a more expensive
material, than “real vulcanized rubber” molds. I bet the company you
went to is using rubber, not silicon, thus the need to use release
on every “shoot” and the poor texture of the waxes/castings. I doubt
tumbling will result in giving you an acceptable piece.
Talk to the company you are having make the molds and waxes and see
what they are actually doing. It they are using “real rubber” ask if
they could make the molds with silicon. If they will, ask them to
keep the release to an absolute minimum if at all. Silicon heat
vulcanizing molds are ok, if it were my “thing” I would use silicon
RTV (room temperature vulcanizing) mold material. You then have a
decision to use either Tin catalyzed mold materials, cheaper but
shorter mold life (about 10 years) or Platinum cured silicon, more
pricy but a VERY LONG mold life. Either of these materials would not
require much if any release and if needed/wanted, I would recommend
using a spray-on Teflon (if you want the source, drop me an e mail
as I have to go look it up in my studio/workshop). This release
works fantastically well, create NO texture in the waxes. I get it
in aerosol cans, by the case, but I use it for a separator release
when making multiple part molds for sculptures my wife Cynthia
creates. She is a retired goldsmith/master mode maker now making
bronze sculptures, mixed media pieces and pastels. If interested you
can see both of our works at MLCE. net. Just click on the
picture/description of the site you want to go to (there are 3) on
the MLCE. net splash page.
If you or anyone else has any questions about what I have posted,
please feel free to contact me via this site’s e mail (for list
perusal) or directly (john at MLCE. net) and I will reply ASAP.