This is Michael Knight at Castaldo.
Molds made with our No Shrink Pink rubber will indeed exhibit 0.0%
shrinkage if done properly – something that requires at bit of
learning and experimentation to compensate for the wide variations in
the generally poor quality of vulcanizer thermostats.
Castings, however, are a different matter entirely. And I’m sure
that the final shrinkage of the finished piece is what you are really
talking about and what you are really concerned about.
Making a mold with 0.0% shrinkage is an excellent first step but
will not produce a final casting with no shrinkage-- there are
1,000’s of other factors involved, all of them introduced by the
A short and partial list of factors includes wax type, wax
temperature, wax injection pressure, sprue length vs. width ratio,
injection time, sprue placement, sprue design, investment shrinkage,
metal shrinkage, rubber mold use temperature one can go on and on.
All these factors will exist even with an RTV rubber mold.