Molding and casting demo by Reynolds Advanced Materials

Molding and casting demo by Reynolds Advanced Materials

There’s lots of ways to mold a cat.

Cast items on display. Photo by Steven Strasburg.

Jay Mazur, from Reynolds Advanced Materials, stopped by Nova Labs on January 25 to lead a demonstration on various types of mold making materials, applications, and techniques. Hailing from Macungie, PA, Reynolds Advanced Materials is a distributor for Smooth-on, a supplier of many different casting supplies to hobby and industrial markets.

Classrooms A and B at Nova Labs were full for the demonstration.

Classrooms A and B were both full of people interested in learning more about what can be done with urethane, silicone, rubber, epoxy, and more. Some of the materials had pot-life (the time you can work with the material after mixing the various parts together) in the two or three minute range, while others remain workable for much longer. A cast of a large silicone dime in Smoothcast 300Q (Q for “quick” apparently!) even had a dramatic reaction going from clear to opaque in a few seconds, surprising everyone in the room. It was pulled from the mold and passed around the room hardly 30 minutes after being mixed and cast.

Pouring high in a thin stream to reduce bubbles. Product was Mold Star 16 Fast – it has a 6-minute pot life and 30-minute cure.

Jay offered tips for working with various products:

  • The ‘double pour and mix.’ – you start by mixing in one cup, then transfer to another cup to ensure that you can thoroughly stir all the hard-to-reach material at the bottom of the container.
  • For foams, mixing part B a LOT before you combine with part A will help – you can add a lot of air to part B without worrying about the pot life (one flexibile foam he demonstrated only had a pot life of 50 seconds, so pre-mixing really helps).
  • You should also keep some clay on hand, just in case the wall around the part you are casting begins to leak.

At the end of the multi-part demonstration, Jay mixed a product called Alja-Safe and had everyone do a life cast of their thumb. After the 8-minute cure time, the same fast-cure urethane used on the dime was used to create reproductions of each person’s casting. At least a few people said that these would be used to create literal USB thumb drives!

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Here are some more photos from the class.

This post was written by Andrew Albosta for the Nova Labs blog, and cross-posted here.