Visual Proof of Pi Educational Toy

I created a toy that lets teachers easily demonstrate how circumference is equal to 2pi*r. Many teachers do things for pi day that are visual and help kids learn about pi and circles. I wanted this to require minimal assembly and supplies. This currently takes a large quantity of filament, and may be refined in the future. The gear rack is actually 1 tooth short meaning that you end up roughly 0.1 inches from reaching 2pi. Additionally there is more backlash in real life leading to some inaccuracy in the visual proof.

100-200 grams of PLA, depending on how strong you would like your print to be.

Print all parts flat for best accuracy and results. I recommend anywhere from 10-20% infill with 2-3 wall loops.

Use the pi nut to screw the gear into the rack.

You now have an easily produceable toy that kids can use to learn and play with.