This past Christmas season I put my printer to good use making unique presents for my family. Everyone with a workshop or a garage got a custom geared light switch cover.
Designing this toy definitely took a few tries to get the desired effect. While doing so I researched and collected notes on perfecting printed gears and I thought it was interesting enough to share. This Instructable is intended as a general guide for designing & printing FDM 3D printed plastic gears.
The geared light switch cover is a neat example of something you should be able to design on your own after reading this instructable.
For those of you who have a 3D printer: you can find the STL files attached to this step for free!
For those without a 3D Printer: I am selling finished Geared Light Switch Covers on my blog here.
Print all parts minimum 3 perimeters all sides top & bottom, with 15% infill. I recommend 0.3mm layer thickness maximum. Any material will work as long as you can prevent warping, which would devastate this device.
The wrench file is the only one that needs print supports/scaffolding.
Assembly Instructions: (Read in full before starting)
1. Clean up the gear teeth with a razor blade so they will mesh smoothly then place them on the plate in the same rotational orientation they were when you printed them. (The pin on the sun gear is to the right and the handle of the ring gear is top and center.)
2. Pin the planet gears in place by pressing the nuts into the holes.
3. Apply a smidge of clear drying glue (glue stick works well) to the business end of the wrench then install it from the side so it snaps on the nut. The glue is to keep the wrench attached to the nut. The wrench also holds the sun gear down onto the assembly.
4. Soften the clips using a heat gun for ~10 seconds. Just enough so they can be opened up. Then align the bump on the clip with the hole on the back of the plate and press over the ring gear. (The holes on the back of the plate may need cleaned up with a knife to aid this, depending on how good your printer is). Then squeeze the clip as it cools. This will ensure that everything is securely held together.