Polargraph Retractable Pen Head

A design for a Polargraph machine (http://www.polargraph.co.uk/) retractable pen head and gondola.

The goal was to create a gondola that could take the pen off of the drawing surface without moving the entire unit. What is lost from the classic Polargraph design are the pivoting arms that ensure that the pen is always at the center point of the two belts suspending the pendulum.

In my version, I laser cut out of plexiglass the round hubs of the gondola and the spacers between the hubs. In the files I include an Illustrator template with these pieces, as well as stl files if you prefer to print them

Additionally I created plexi stepper motor mounts for the large motors needed to drive the larger scale machine, as well as counter weight brackets.

Thanks to Sandy Nobel for his machine design and software.

This project was built at the MadSci Lab. The content drawn by the machine was designed by Rui Pereira.

Details and video here:
https://www.instructables.com/id/Large