Use a Model Train Transformer to Cut Foam


Makezine_COTM_Transformers-BadgeSure, you can buy a foam cutter, but wouldn’t it be much more satisfying to build your own? MAKE author Bob Knetzger–who wrote this great Desktop Foundry project, shows how to built a foam-cutting rig with a length of nichrome wire (similar to the elements you gave in your toaster) and a model train transformer.

It turns out a transformer is ideal for controlling the hot wire. Not only does it deliver the amps you need (divide the volts by the nichrome wire’s resistance to get amperage; OHAI Ohm’s Law!) but they typically have a speed controller (potentiometer) allowing you to adjust the temperature of your cutting rig based on the materials you’re working with.


My interests include writing, electronics, RPGs, scifi, hackers & hackerspaces, 3D printing, building sets & toys. @johnbaichtal

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