Kinetic sculpture

thingiverse

I wanted to create something with gears for the very first time, and I have to admit that scotch yokes catch my eye big time. So I made this useless machine - it works, but I'm pretty sure I won't be able to walk past it without stopping to turn the crank, and it doesn't do anything beyond putting a smile on my face like a goofball. Video of it in action: <iframe width="560" height="315" src="https://www.youtube.com/embed/-PpTpAVn2Kg" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe> To make one of these, you'll need: 4x 18" steel rods with a diameter of about 4-5mm 15x 4mm x 30mm bolts, washers, and nylock nuts 1x 18"x18" piece of plywood, wood, or laun - I used luan because it was cheap and had a nice finish 5mm or equivalent drill bit and drill Super glue For printing, I used ABS, but I can't see why PLA or other blends wouldn't work just as well. Unless noted, most parts don't require printing with supports: 4x wedge2 1x gear_handle 1x gear_idle 1x gear_south 1x gear_north 1x gear_east 1x gear_west 1x gear_main 2x log_rodholder 2x log_scotch_yoke (use supports) 2x lat_scotch_yoke (use supports) 2x lat_rodholder Assembly: This build is pretty easy, so take your plywood and draw a line down the middle in both the X and Y axis. Attach the gear_main in the center. Line up the gear_east, gear_west, gear_north, and gear_south to their corresponding cardinal directions, and position the handles of those gears where they're closest to the center of the gear_main. The axel holes of each gear should fall on the X/Y line you've drawn on the board. The lat_ and log_ rodholders correspond to latitude and longitude directions, as do the lat_ and log_ yokes. The rodholders are different heights because one axis goes under the other. Run the rods through the yokes but leave them loose at first to make sure they're sliding freely along their rods - the yokes don't get hung up on screw heads etc. You may have to raise the rod holders with some washers if your bolt heads sit too proud. The gear_idle and gear_handle can be placed a bit more free-style, just mate the idle gear to the main gear, drill, and attach followed by the gear_handle. Once you've got everything moving smoothly (don't tighten any bolts too much!), you can use super glue to attach the rods to the rodholders. Finally, add the wedge2 pieces to the holes in the yokes. Update: I needed an excuse to experiment with my printer's settings and decided to print out these pieces at 50% of their original size - works great! I'd recommend setting your printer speed pretty low and printing with cooling on (even with ABS). Another treat for doing it at 50% smaller is that you can affix the gears to a board with tiny nails. For the rods, I used floral wire at first and then upgraded to clothes-hanger wire - works really well and makes for a good desk toy.