This is a simple Spirograph style LEGO drawing machine, loosely based off an old drawing toy from the 1950’s called the Hoot Nanny or Magic Designer. It can create many different patterns by changing the configuration of the model. You can also draw multiple patterns on the same piece of paper to create even more complex designs. Check out the video to see how it works. You can also find building instructions, along with some construction notes, below.
For best results you’ll want to use a pen or marker that glides very easily over paper and can deposit ink with very little pressure. I’m using a Uni-ball vision fine point pen. A regular ball point pen doesn’t seem to work unless maybe you strap some weight to it. A pencil will also work.
If you’d like to reproduce the patterns shown in the video, you can see how the machine is configured in the following pictures. Be sure to duplicate all of the connection points of the armature and also note where the fixed anchor is located.
As I mention in the video, the central gears will result in the pattern repeating 27 times in one rotation of the paper. You can customize this ratio by replacing any pair of meshed gears. For example, instead of using one 8 tooth and one 24 tooth gear, you can use two 16 tooth gears, or one 12 tooth and one 20 tooth gear.
Have fun experimenting with your own designs!