EggBot Makerbot Attachment

thingiverse

This device enables your Makerbot or other CNC machine to print/draw on curved objects like cylinders and spheres, similar to the EMS EggBot (http://egg-bot.com/). It operates by linking one of the machine's axises to a stepper motor, which then rotates the workpiece. The workpiece is held between two centers that are supported by two brackets - one houses the stepper motor and the other hosts a 608 bearing. These brackets mount on a dovetail way for adjustable positioning according to different workpieces. To assemble, print the parts listed in the parts list, along with your chosen centers. A heated build platform is optional but helpful. You'll need at least two centers: one for the motor (depending on the shaft diameter) and one for the bearing ("end__stl"). Insert the bearing into the End Bracket, then install the stepper motor into the Motor Bracket. For each bracket, insert a bolt into a clamp ("clamp.stl"), push it through the hole in the bracket, add a washer and wheel ("wheel.stl"), then tighten the nut onto the shaft. Align the bracket with the base and secure the clamp. Connect the stepper motor to your machine, ensuring safety measures are followed for Makerbot stepper drivers. For software setup, use Replicatorg but establish a relationship between linear distances in gcode and rotation of the motor by modifying the machines.xml file. Choose a distance (e.g., 10cm) and divide it by your chosen distance in mm to find the corresponding value for the axis scale property. If using a Makerbot, connect the device to the Y axis. To use, loosen the clamps by turning the wheels, move the brackets far enough to insert the workpiece, push the brackets into place, and tighten the clamps. Cup centers may need additional hot glue for a secure grip on curved surfaces.