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The polymorph thermostat

controls an electric kettle or an electric plate so that when it is filled with water, its temperature is kept constant at 62 degrees or any other temperature you set.
This allows you to throw your polymorph plastic bits into the water, and take them out when they are completely soft and transparent.


what is PCL

Polycaprolactone (a.k.a PCL, Polymorph)
is a plastic material that melts/becomes soft at 62 degrees celcius.
It also becomes transparent at this temperature.
When it cools down, it becomes hard and non-transparent again.
in its hardened state it canebe painted, drilled and sanded.
And most important, it is fully recyclable!! Take all your remaining PCL pieces and you can melt them again and again for reuse!!

(The picture above shows the water temperature at 79 degrees. This should not happen normally, but shown here when the controller was still running with older settings.
Under normal usage conditions, the temperature may fluctuate no higher than a few degrees above the set temperature).


The box has one 220V power input, one output that is turned on when the temperature controller senses that it is too cold outside.


The PID controller can be bought on the markets for a 10-20$ - RX-700 manual (pdf)

Also note that the C700 had been modified to drive an SSR instead of the original Relay, as described in this video for the C100.


The C700 modification is very similar. The original Relay had been partly soldered in the loation of the Alarm 2 relay, but it is of course unused. The SSR output can be thought of as a CPU output with logic levels 0V or 12V, and a series resistor of 1K to limit the current to the SSR. In addition, the 3rd pad on the C700 had been drive directly with the 12V control output. This can be used, in combination with the GND pin, to drive the 12V fan left inside from the original PC power supply. The full details, and exact pin numbers can be found on the C700 itself, on its sticker.


The box is fully functional, but there are a few rough edges that needs to be fixed:

  1. The Solid State Relay inside the box needs to be screwed on the chassis. This should provide adequate cooling for it, since it is hardly turned on.
    In order to do this, the chassis needs to be drilled at 2 places and 2 screws needs to be added to hold the SSR in place.
  2. We need to label the box and its cables.
  3. Make sure the cables are kept with it - I prepared a special cable for it that ends with a regular 220V socket for the kettle to be plugged into.
  4. Get a dedicated electric kettle for it and saw it in half for easier access, or get an electric pan, which is wider and more convenient.
    If anyone knows where to get a used one, it would be great.
  5. Add 4 rubber feets (the simple ones with the hole in the middle). The Power supply box housing the PID controller already has 4 screws ready for something like this. We copuld use something along the line of: http://www.amazon.com/Rubber-Feet-Large-Tapered-Washers/dp/B004H6A0KI
  6. Add a sticker/printed paper with a QR code pointing to this page!