Jonathon, keep in mind that all silicones including RTVs will not
last as long as natural (organic) rubber. This is not a concern for
jewelers who do not do huge runs.
The storage life of finished silicone molds is essentially forever,
which suits most jewelers. In high production situations they will
wear out a good deal sooner than natural rubber.
Just the same, it is often a good idea to take advantage of the
special attributes of silicones, such as ease of release, and in
cases such as with Akron 4X ZeroShrink, where detail replication is
exceptional. Many manufacturers will plan to make more molds through
a given run. Over a long run, the cost of making a few replacement
molds does not impact total cost very significantly and is easily
offset by labor savings in process.
Some manufacturers report as high as double speed in wax production
with silicone molds.
Zero-D Products, Inc.
precision engineered materials solutions