Playing with PCL
PCL melts at low temperatures. Photo: cc-by-2.0, Steve Jurvetson
PCL melts at low temperatures.
Photo: cc-by-2.0, Steve Jurvetson

One of the coolest materials for making is a moldable plastic called Polycaprolactone, or PCL. You may have seen it marketed as Shapelock, PolyMorph, InstaMorph, ThermoMorph, or other brand names.

PCL is typically sold in small round pellets. The pearly white material melts at about 140 degrees Fahrenheit (60 degrees Celsius), and becomes transparent and pliable as Silly Putty. Then you can shape it however you like, and it can be re-melted and reformed many times. Once hardened, PCL can be cut, drilled, filed, or worked in any number of ways. This makes it perfect for making prototypes, performing repairs, and making all sorts of customized stuff.

While I’ve seen many cool things made with PCL, some of the most creative techniques I’ve heard of were developed by a friend of mine, Gareth from Let’s Make Robots. Gareth developed a series of workshop posts showing how to form useful shapes, add color and more neat stuff. Another Let’s Make Robots member, Russell, posted a tip on how to make sheets and brackets from PCL.

The links for all of these posts are below, so go check them out and give PCL a try.


Andrew Terranova is an electrical engineer, writer and author of How Things Are Made: From Automobiles to Zippers. Andrew is also an electronics and robotics enthusiast and has created and curated robotics exhibits for the Children's Museum of Somerset County, NJ and taught robotics classes for the Kaleidoscope Enrichment in Blairstown, NJ and for a public primary school. Andrew is always looking for ways to engage makers and educators.

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