This is a printable opto flag for the Fleming CNC Isaac. It is much more robust than my previous designs,This works with the Fleming CNC Isaac. It can be found at flemingcnc.com.I found wrapping in aluminum foil and heating with a lighter, followed my a cool down on a flat surface creates a strong bond with the PLA I am using to create a IR resistant surface.I printed one alone with decent results, but two in parallel yielded much better results... http://www.youtube.com/watch?v=V8lW-JvToKAThe detector faces towards the belts and mounts through the middle hole on the PCB.