Planetary gearbox extruder

A compact extruder with an integrated 5.6:1 planetary gearbox.

3D printer parts and enhancements

Creative Commons Attribution Share Alike

Commercial use is allowed, you must attribute the creator, you may remix this work and the remixed work should be made available under this license.

Learn more or download attribution tags


There were mistakes in the cover and base, which crept in at the last minute - I've fixed them, and posted those parts as their own files.

I've tested this extruder over 2 days of fairly continuous printing with little sign of wear.

OpenSCAD sources available on GitHub -

Print the parts with PLA, or another wear resistant plastic.  If you're worried about heat, print the gearbox parts with PLA, and the other parts with ABS.

Using a small screwdriver, break the support structures from inside the nut and bolt head pockets.

Insert M3 nylock nuts into all of the nut pockets.  I find that using a bolt to align them before pushing them into place usually works well - if not, then I use the bolt to pull them into place.

Remove the support structure that blocks the bolt head recess in the upper planet carrier (either drill it with an M5 drillbit, or just cut it out with a hobby knife).

Insert the M5 bolt into the upper planet carrier.  If necessary, use the drive wheel and a nut to pull the bolt into place (then remove the drive wheel and nut).

Assemble the rest of the planet carrier, along with its gears, using 3 M3x6 bolts.  There is an alignment notch on the side of the carrier to assist with assembly.

Attach the sun gear to the motor.  Use threadlock to secure the screw.

Attach the base to the motor using 4 M3x10 bolts.

Insert one of the 105 bearings into the cover, run the drive bolt through the cover, and fix it in place using the drive wheel.  Use threadlock to secure the screw. Be certain to leave a small gap between the cover and wheel so that the planet carrier rotates freely.

Align the ring gear to the planet gears, and position it against the cover.

Align the planet gears to the sun gear, and position the ring gear against the base.  Attach the cover to the base using 4 M3x25 bolts.

Insert the 623 bearing into the pinch wheel bracket, and attach it with an M3x16 bolt.

Insert the other 105 bearing into the extruder frame.

Align the extruder frame and pinch wheel bracket with the cover, and attach it using 3 M3x16 bolts.

Fix the drive bolt in position using the M5 nylock nut - be sure to leave it loose enough to allow things to rotate smoothly.  (I've found that after breaking the gearbox in, I have to insert an allen wrench into the drive wheel's set screw to prevent the gears from rotating while I tighten the M5 nylock nut.)

You'll notice that I haven't told you when (or where) to grease it.  That's because I run it for an hour or so to make sure everything is broken in before I grease it.

Break it in, tear it down, grease the insides of the planet gears, and all gear teeth, then reassemble.

Materials and methods

- PLA or other wear resistant plastic.
- 2x 105 Bearing - [Source: HobbyKing](
- 1x 623 Bearing - [Source: HobbyKing](
- 1x 10T/5MM M1 Pinion - [Source: HobbyKing](
- 1x 5mm x 12mm x 11mm Drive wheel - [Source: Reprap Discount](
- 15x M3 Nylock nut
- 3x M3x6 bolt
- 4x M3x10 bolt
- 3x M3x16 bolt
- 3x M3x20 bolt
- 6x M3x25 bolt
- 2x M3 washer
- 1x M5 Nylock nut
- 1x M5x30 bolt
- Threadlock
- Grease



Issues are used to track todos, bugs or requests. To get started, you could create an issue.


1ae36ad5c876e84c94b510a43268532d?default=blank&size=40Kitol added this to the tools collection ago
Cff72edb751e48f3c62702b540173917?default=blank&size=40Renega added this to the Mechanika -meghajtás collection ago
Cff72edb751e48f3c62702b540173917?default=blank&size=40Renega added this to the Nyomtató collection ago
Fcb3469695c95a5e23c2429eaae67447?default=blank&size=40Adam Rękosiewicz added this to the mods collection ago
04f062af5acb9d6d4079618a90953c1d?default=blank&size=40pjk22 added this to the extruder collection ago
0713fc717563d0668167c27ade52f10c?default=blank&size=40Roy Prawira added this to the 3D Printer collection ago
9a6874d9b07e9bbf3c25502f5fdf46df?default=blank&size=40Bykster43 added this to the Things to print collection ago
079e15efe4b161dd7bf8c72b8b88c7a8?default=blank&size=40amkza added this to the Cool Projects collection ago
Mini lisca mangaLisca added this to the 3D Printer Parts collection ago
Mini ataraxis glow bigataraxis commented ago

hey lodran, i like the design - thank you for sharing!

could you please share the sun too (just for testing).

cheers, flo

Mini lodranLodran commented ago

The sun gear is a vitamin, purchased from hobbyking.

At one point, there was a sun gear in the openscad sources, but I found that it was extremely unreliable, and caused far too many failures.

B36d6b479e2a4adf7be95948044ba9a3?default=blank&size=40motorimicro commented ago

i don't find the sun gear!!! in the draw there isn't

908972d712d3431b629e58e1465017b5?default=blank&size=40ChriRas added this to the Planetengetriebe collection ago
Cbd09987550087b356078f936a394df9?default=blank&size=40rafael_l added this to the extrusores collection ago
24ee2577539ae18c4b0af758a9234ad4?default=blank&size=40Tongdam added this to the Extruder collection ago
Acacbff64b0aff3dde7e149f4f1f3dfd?default=blank&size=40favabr added this to the reprap collection ago
Mini lodranLodran published this design ago