STEP 11: Making Rubber Molds and Casting the Parts
Continued ...
equal parts of the A and B component in a small
plastic cup, stir the mix together and then pour into
the mold.
There are different versions available. I used the 300
which has a three-minute pot life and a de-mold time
of 10 minutes. Hindsight being 20/20 I wished I had
picked up the 305 which has a seven-minute pot life
and a 30 min de-mold time.
Once you hit the pot life limit, it begins to set up. I
also discovered that the pot life is very temperature-
sensitive. The higher the ambient temperature, the
faster it sets up, so you need to have everything
ready to go. You will also need a release agent to
spray on the molds. I use a mold release agent from
Casting Craft. If in doubt, talk with the sales people
at the art store. They were a tremendous help to me.
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