I have been reading with deep interest, the exchange relative to
repairing tiny voids in wax patterns. There is clearly a number of
products being sold which help repair the defects, as well as plenty
of astute methods of repair.
Solutions such as snipping and burning defects or bumps out of the
mold cause me to ask–why are there bumps in the mold? There seems
to be a good deal of this going around, given the number of people
who have ready solutions to the problem.
Your mold rubber should provide you with a perfect copy of your
model. If there are defects in the model, correct them. If you end
up with defects in the mold pattern just the same, then your rubber
is either defective, or your mold making technique needs help.
I appreciate all of the very astute help offered, but there is one
misconception I wish to correct. That is that silicone RTV is
"softer" than the vulcanizing rubbers. Actually, some are and some
are not. You can buy silicone RTV in hardness ranging from 25 Shor A
to 90 Shor A durometer. The natural rubbers are in the range of 35
to 40, while the heat cured silicones range up to 70 Shor A.
I have been developing and manufacturing mold rubbers and injection
waxes since 1990. I have developed natural rubbers, heat cured
silicones and liquid and putty RTV types.
I welcome any opportunity to help you clear up some of the mysteries
of the process or any problems you may have with the materials you
Zero-D Products, Inc.