mount – Engineer On The Loose

I just finished printing both motor mounts for my work-in-progress Polargraphic Plotter / Drawbot / Plotterbot. I decided on these motor mounts on Thingiverse. They fit a NEMA 17 motor and they looked simple and easy to print. Although I am a little concerned about the print layers being parallel to the mount bolt holes.

I printed these on my MendelMax 3D printer in ABS. I printed the mounts one at a time and each mount took a little over an hour to print. The prints needed some clean up with a pen knife to trim off the danglies but after that they look good. The motor mounting holes line up nearly perfect and the mounts are good fit to the motor bodies. We’ll see how they hold up under load but if I use a washer on the mounting holes it should distribute the stress.

My MendelMax printer

A two-for-one special, 0.5 mm printhead off of ebay. It seems to print ok.

The motor mount finished and ready to remove from the bed.

A video of the motor mount being printed

Another part down. Now on to the filament spools….

I’ve decided to use an Eggbot control board, the EiBotBoard, to drive my polar plotter.

Not for any particularly wonderful reason. The board costs right at $50, which is the cost of an Arduino uno R3 ($30) plus an Adafruit Motor Shield ($20).

It seems the software to drive a polar plotter already exists for the Arduino / motor shield combo. Eggbot board, not so much.

So I’m looking at the same cost and more work to use the Eggbot board. But hey, if it was too easy it wouldn’t be fun :). I like the form factor of the EiBotBoard and if I can get it working as a polar plotter I can add a little back to the community.

I ended up buying the EiBotBoard from Sparkfun, the stepper motors from Pololu (on black friday sale for $14 each), the power wart from Adafruit.

The motor mounts, filament spools, and gondola I’ll download from Thingiverse and print them myself.

I’ve decided on the following parts:

Motor Mounts