Knurled 17P Herringbone Planetary Gear Bearing

To print successfully please read!

- -> Set Slice gap closing radius to 0.049                 <---

- -> Disable the Avoid crossing perimeters option   <---

About the file names:

The files names are numbered. The convention is flank gap in mm then root clearance mm.

Example of reading the leading 4 number in the file name:

0808PlanetaryBearing_OD104.5_ID60_H10_S72P13x17R98_b30_e0.08_tp0.025.stl

the 08 08 mean 0.08 for the flank gap and second 08 is the root clearance.

Bigger means looser at the risk of skipping & smaller means tighter but at the risk of a fused part!

Outer dimension is shown with OD in the file name.  They are all 104.5 mm OD

Inner dimension is shown with ID in the file name.     They are all 60 mm ID

H is height in mm. 10 mm for this design.

S72 means the Sun has 72 teeth.

P13x17 means 13 teeth for each of the planets with a total of 17 planets

R98 is ring with 98 teeth.

e0.08 was the tolerance setting, but to be clear I specified flank and root gaps in the leading numbers of the file name.

tp0.025 is the taper flank angle. Which is 0.025 mm.


The file that worked for my machine was:

"Default-flankgap0.1Rootclearance0.08PlanetaryBearing_OD104.5_ID60_H10_S72P13x17R98_b30_e0.1_tp0.025.stl" 


Please note I still had to compress the ring and break loose the stuck planets before it turned. I then performed the water trick which instructions for that are below.


The zero file  is not recommended for printing. It is only there for completeness. Unless you have the technological machinery to do it - don't waste your material and time.

If you had a resin printer you may be able to print the other tighter tolerance files.




Material Choice:

If your print fails with one color, please note that some colors expand and contract more. Using PLA of the same brand but in different colors is sensitive to the tolerance. If your printing a tight tolerance you may notice that the part could be fused in olive green but not be fused in orange or white. Even with the same print file.

Typically Silk PLA needs a looser tolerance.
Where regular PLA can take a tighter tolerance.

Since I only tested this in PLA   -  I cannot guarantee it will work in another material. 




Stuck or fused part:

Based on how stuck the part may be - you may be able to free it up to spin.

To attempt to break it free gently compress it to a slight elliptical shape and roll that elliptical shape around it to break any sticking planets up. Gently or you will break it or permanently distort it. Pinching a planet with your fingers and moving it axially may also snap it loose.

If its still stubborn, then try another of the stl files with 1010 or 1212 or higher leading in the file name.

Check your Slice gap closing radius and Avoid crossing perimeters against what was instructed at the top.

Disabling Avoid crossing perimeters stops a software bug from layer shifting.

Slice gap closing radius needs to be a small number so the planets do not fuse/cross perimeters with the sun and sun in the slicer's generated tool paths. 


To make it spin even better use the water trick I found.

The Water Trick:

Put it in water bowl or running under a tap and move it. It must move while under the water. Sitting in water will do nothing. Move and work it in under water. After a while of working it, pull it out and dry it. When its fully dry it should spin well - dependent of course if your material is good and your printer did a good job.