Egg Decorating Bot

Eggs Decorated by Egg Deco Bot, held in hands.

I started this project in 2017. My original goals were:

  1. Don’t use a 3d printer or laser cutter.
  2. Build the frame out of foam core.

As you can see in the thumbnail, I gave up on the foam core, but I stuck it out on the no 3D printing or laser cutting, just to prove I could.

In 2017, I made a foam core frame (that I failed to take pictures of) that couldn’t really hold up to the pressure of holding and egg. Specifically the back pressure of the spring kept pushing the hot glued bearings off axis.

After solidly missing Easter of 2017, I decided to move to a wooden and threaded rod frame shown above. I started it in 2018 way to close to Easter to have a chance to have it done. After that, I tended to work on it a few hours a year in the few weeks before Easter. I had a hard time finding something to hold the egg nicely. Mostly I tried using suction cups and different wants of holding them. That is what I spent 2019, 2020, and 2021 working on (although, remember it was only a few hours each spring really).

For 2022, I was sick of not completing this and was determined to do whatever it took to get it done, and if I failed, I would abandon it. In the end, I cheated and ordered some aluminum with spongy material and grip tape pieces from a place selling parts for knock off egg bots. These worked nicely finally. I can’t believe it took so long.

Then it was a race to finish the electronics. I just used simple off the shelf stepper controllers and an ESP32 module. The ESP32 was programmed with the Arduino IDE. There was no G-Code interpreter or fancy control system. There were just different generative Arduino sketches to move the pen.

It turns out that the frame didn’t really allow the arm to move back and forth across the egg enough to let you do more than a fairly narrow stripe around the center. Oops. I’m still calling it done.

I have ideas for the future, but I don’t know if I will pursue them. I am certain that if I decide to try again, I will start over with a design someone else made as a starting point.

Really the only 2 ideas I am interested in trying out currently are:

  1. Using LinuxCNC instead of the more common GRBL.
  2. Finessing how generative sketches can be created and previewed.