Fidget Spinner - 3D Printed

Seems like spinners are trending right now so I thought I would design one.

Here is my take on a fidget spinner. Designed in OpenSCAD. I made two models.

My print settings:

PLA, 190 degrees Celcius
Heated bed at 50 degrees Celcius
0.4 mm nozzle
0.3 mm layers
40% fill (for weight = more momentum)
No rafts
No supports

Bed coated with 2 layers of Glue Stick (Target brand that changes from purple to clear)

Materials:

1 or 3 608zz bearing (bore diameter 8 mm, outside diameter 22 mm, width 7 mm)
PLA fillament
WD-40
Jar or oil resistant container

Tools:

Computer with OpenSCAD (if you want to change design), printer host and slicer software
3D Printer

The bearings, especially brand new ones are packed with a really thick grease. Now this grease works great when the bearing has a heavy load on it, like a person standing on a skateboard. All the inertia from all that mass will easily overcome the viscosity of the grease. However, it does not work very well when we are dealing with something light like a spinner.

So the grease has to go. I tried Dawn dish soap and hot water, but soap and water requires a lot of mechanical work using a toothbrush and also a lot of hot water. The best solution is to dissolve the grease with WD-40. Put all your bearings in a jar. Add WD-40 until at least half the bearings are submerged. Cover the jar and set aside. Swirl it around twice a day for two days.

After two days, remove the bearings from the jar (save the jar and WD-40). Soak the bearings in hot soapy water for 10-15 minutes. Move the bearing around in the soapy water to remove as much of the WD-40 as possible. Rinse with hot water and let air dry for at least 1 hour. Give them a spin. If all the grease is removed, the bearings should spin freely for at least 5 seconds.

Choose which one you want to make depending on how many bearing you want to use.

If you are using three bearings then the infill can be 15%-20% (MySpinner_x_3_608.stl). If only using the 1 bearing design the infill should be 40% to give the spinner more mass (MySpinner.stl).

Attached are the files. I have included the SCAD files in case you want to change the design. Just to warn you, i am not a programmer, so my code is sloppy.

Printed on my printer, the bearing press in by hand and stay firmly in place. in the scad design i have the bearing holes at exactly 22 mm diameter. if on your print the bearings are too tight or too loose scale the model up or down a couple of percent.

After the print, do your post-print cleanup work (if any).

push the 608 bearing(s) in.

Give it a spin.

Spin time with one bearing is about 35 seconds. Spin time with the much heavier 3 bearing model is about 1 minute.