With this easy to print wheel, you can convert the first 8 numbers (starting from zero) into their 3-bit binary values!
There are two versions of the wheel, two-colors and monochromatic.
In the colored version, the 0/1 bits to be ignored are automatically “hidden” because the background will have the same color of the needle. So, the 0/1 to be considered are the ones colored as the primary color of the wheel (yellow in my posted photo).

Bonus info: the hidden bits, represent the ones' complement of the other bits ;-)
In the monochromatic version, the 0/1 bits to consider will be the "opened" holes
All the STLs are saved with the suggested print orientation. See printing details for the 2 versions in the following sections.
Files to be used:
3bit_wheel3bit_wheel_needle3bit_wheel_nutFirst print the wheel using 2 colors (one light and one dark, the more different the better), adding a color change in the slicer at height 2.8mm (manual filament switch is fine).
Print the needle and the nut in the same job if you want. The nut threaded hole and the needle threaded bar have a small tolerance of 0.05mm, so they should connect without problem.
Notes:
Files to be used:
monochrome_3bit_wheelmonochrome_3bit_wheel_needle3bit_wheel_nut (the STL is the same for both versions) This version should be printed with one color only because the 2nd color has been replaced with "negative" volumes. The needle and the wheel are slightly different in size than their two-tone counterparts, the nut is the same.
You can print all the three files in one job if you want.
The author marked this model as their own original creation.