so RAMPS and other boards conveniently include two stepper motor connectors on the Z stepper. To address this, you can connect the X motors to the stepper labeled “Z”, and the Z motor to the stepper labeled “X”, then modify the firmware source code and swap the pin assignments for the “X” and “Z” directions. (In Marlin, you’ll need to modify the pins.h file.) Additionally, you should turn off hardware endstops and temperature control from the firmware until you decide to install endstops and a fan.
GCode Precautions The software endstops in the firmware provide sufficient safety for the QuadRap. You can give the firmware the maximum printable volume, manually move the XY carriage to the desired starting position, lift
the table by rotating the threaded rod, or moving the Z axis in your print host, and disconnect/reconnect the host software before starting the job. So far for me, it has never happened that the extruder left the theoretical printable zone. If you happen to go further and disable the software endstops as well, you’ll need to check the ending GCode in your slicer settings to replace the “home axis” command with something like G91 followed by G1 X30, which tells it to use relative coordinates and move some distance away to move the nozzle away from where it can ooze onto the printed part.
Future Plans • 300 gram quad color extruder • Street Painter Bot on omni wheels based on RAMPS 1.4
QuadRap top view