I have made a USD 2,- handheld cutter head for the PWM controller desribed in my previous blog post. The handheld cutter is nice for trimming off edges and so on. The spring keeps the wire tensioned. The final version don't need a series dropping resistor as the PWM driver stage uses two FETs.
The controller has also has been tested on a vertical setup for cutting spacers to my KFM3 depron wings (below):
The cutter gives nice clean cuts for vertical cutting operations (below). Please note the fan that sucks gases out from the workpiece. This is very important because blue and red foam gives off fumes that are very toxic when they are melted.
The PWM controller outputs pulses and is configurable both in duty cycle and several other parameters (below).
Based on interest, I may make a kit available.