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This is Shapelock/Friendly Plastic: surprisingly strong, a little goes a long way, good for kids!
on July 2, 2010
I heard about this as "Shapelock" and for whatever reason, the company decided to rename it "Friendly Plastic". "Instamorph" is another name for the same material.
It's Polycaprolactone, Wikipedia has a great entry on it.
The pellets melt in 150F-160F water. This is hot enough to scald you but not cause a serious burn. I was afraid this would mean that kids wouldn't be able to play with it but in fact they can due to the low thermal capacity and conductivity. Within a minute or two of coming out of the hot water bath this stuff cools down enough that it's just warm. However it still remains pliable enough for kids to have a lot of fun.
When it does finally cool completely it's hard and strong. I'm used to Fimo/Sculpey which is really very weak. This stuff is suprisingly strong. Strong enough that I have yet to break a part which was fully cooled. I'd say it's as structural as the plastic in most kid's toys and actually a bit tougher (resistant to cracking) I believe there must be some crystallization going on. I made a device where the plastic acts as a living spring - it flexes with a surprisingly high modulus.
I've made a number of things with it already - a cell phone holder, a shoe horn, a cable organizer, even special hook to hold an IV bag on a light stand.
You don't use much of the material because any pieces you have are easily remelted into your next project. Once something outlives it's usefulness you simply melt it back down.
1) Stretch out leftover pieces so they're not too solid - this speeds up remelting later on.
2) Get the little container first unless you definitely have something in mind. I bought the 28 oz to start and despite using it quite a bit, I have barely made a dent - as mentioned, you re-use any leftovers.
3) You can also use it as a glue. When it's heated to the clear state (160F) it is very sticky.
4) Make your parts in sections. When done, you can dip in hot water to melt the surface and then stick the sections together.
5) When making pieces, keep a hot bath (pot on stove) and a cold bath (Ice water) so you can soften/harden easily
6) Put a thermometer in your hot bath and try to keep it at 150-160
7) Don't forget that you can carve, drill, cut, and even tap the material once it's cooled
8) Be patient! There's definitely a learning curve to making good parts.
If you have questions or comments, or if you found this review helpful, please let me know!