This is sort of a derivative work of ToM Extruder Relay Fix by M_G http://www.thingiverse.com/thing:9130 Which is itself a derivative of ToM Extruder Relay Fix http://www.thingiverse.com/thing:5569 by MakeALot http://www.thingiverse.com/MakeALotThis uses transistors instead of Relays. Perhaps some will find this useful if they don’t have access to relays. A variant of the ToM Extruder Relay Fix for dying extruder motors that operates in the forward and reverse directions. This thing uses 4x NPN Transistors, 2x resistors and 4x 1N400X series diodes.I have not yet built this myself though!