Harmonograph

" I don't think that there is any scientific justification for Harmonographs, unless one remembers that they are used to draw the fancy repeating scrollwork on paper currencies. But physicists and civilians continue to be drawn to them, fascinated by the patterns they produce.
"Harmonographs are mechanical devices that trace out the resultant of two or more simple harmonic motions, typically along mutually-perpendicular axes."
--- Tom Greenslade, from descriptions of the Kenyon College apparatus collection

The device is constructed using a table I bought online for $40.
Three electrical outlet covers.
Eight Phillips head screwdriver bits.
Five fidget spinner bearings.
Sixty pounds of steel weights.
Three 3/4" by 48" wooden dowel rods.
Three 0.375" by 2' square wooden rods.
Three clamps for weight height adjustment.
Misc. bolts, screws, and clevis pins.

Here's a quick video of the harmonograph in operation:
https://www.youtube.com/watch?v=ARXCmEckJ6Q

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