3G 5D Mini

Add a reliable stepper extruder to your original MakerBot Cupcake using this little board.

This board adds a fourth stepper channel to the original RepRap Gen3 electronics by repurposing one endstop pin from each axis. It's software-compatible with Tinkerings' original 3G 5D Shield, so it works with firmware available through RepG. No hacks required.

Unlike the original, the Mini doesn't break out separate endstop connectors, or provide ANDing of endstops. But fear not! Endstops still work using the old-school connectors on the Gen3 Stepper Drivers -- use one per axis without changing a thing, or convert them to open-collector to use two.

For more information and current revisions of the files, visit: http://cliffle.com/project/3g5d-mini

Update 2012-02-20: Shrunk the board by another 300 mils vertically and a bit horizontally. Now measures 3.775 x 0.65 inches, giving improved clearance for the all-important reset button.

Update 2012-03-05: Boards are back from the f