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Planetary gearbox for bowden extruder

by Trigubovich Jul 15, 2017
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I combined this with a few other bits and pieces to make a compact extruder:


The gearbox was assembled with threadlock to keep nuts from coming undone and white lithium grease to lubricate the gears. The printed parts are all eSun PLA+.

I don't yet have it running on the Hypercube 300(ish) for which I built it, but I've been testing it on an Anet A8 and it looks like it'll get the job done:


Compact Geared Bowden Extruder
by salfter


i just remixed the Thing to fit a 3mm Screw and a F623ZZ Bearing (3x4x10) on the same principe. Uses m3 Bolt and Nylock Nut or M3 Hex Bolt instead of a M5 Hex Bolt.

I use it like this, cause i had no bearings for 5mm left, but many for 3mm. On the outside i use a 5mm Round Spacer from a FPV Drone to have a blank 5mm shaft for the Extruder Pulley.

Thanks for the reducer !!! Tomorrow I'll try to print and try it on my MKS. This extruder uses a weak driver / amperage and only 12 volts, and because of this the engine can not pull the thread. The only way out is the reducer !!! Many thanks!!!

Sorry, I don't completely understand how to assemble it. Should I drill holes for satellite gears nuts and output shaft?

Yes, it's a thin layer.
This makes it possible not to print supporting material.

Awesome design but just curious what is the point of this for extruders? How does it help the 3d printer?

Sometimes the engine is too weak to squeeze out the filament,
therefore it is necessary to use reducers.

Did exactly what I needed it for, thank you

I'm glad that anyone needs it )

Too complex, fragile, heavy. Besides, printed gears are a non sense in this kind of application.
As usual, no specification, no demo.
People liking these kind of design always amazes me.

What amazes me is people that have designed absolutely simplistic holders and such, criticizing beautifully designed and functional items such as this one. No wonder you are so disliked and laughed at in the builder community. Clown.

Thanks for taking the time to design and post this Trigubovich. I love it.

Dear Mozak,
thanks for the positive feedback.
Do not pay attention to that guy, for him does not work, for other's work.
If he is sure that this does not work, it will not work for him ever
I have reprap delta with 3 color and these reducers work fine.
And that guy - bevangg, printed this gearbox with bearing, made a video, that it works and for some reason deleted his account )

for: MKSA

here is one guy tells:

I have already shown this, but I repeat:

the guy just has a bad mood )

Planetary gearbox for bowden extruder

What amazes me is that a retard who din't publish anything, is unable to understand if a design is valid or not, is indeed nobody, dares to voice an opinion !
Now, retard, how about making this thing and showing it working ? (You opinion qualifies you as a retard)
Because you see retard, a few posts below a guy made it just to prove it wasn't worth it !
BTW: I don't care about negative comments on my things as ALL of them are from people who failed to show anything worth, working, useful.

No certificate, no warranty service, no free shipping ... )
Excuse for troubling

:) understood my friend but the terms were not stated!

@MKSA I concur, it is a good design in theory but there is no end bearing and uses screws for shafts. So would not last very long even if it did work.
I printed one just to prove that it did not work. If you put an end bearing on it is almost usable. But the gears are so thin that they cannot take any lateral force without jinking and seizing the entire mechanism and the stepper.
I think it might be possible to get around these problems, at least partially, and will update you with progress if I have any! Including parametric files and videos of it working if that ever happens.
This design is not usable for it's stated purpose as an extruder but could still be used as a simple in line reducer gear. In fact with no lateral force on the output shaft it works perfectly.
Thanks to Trigubovich for posting it, it has inspired me. But perhaps you should mark it as a work in progress until you can show it working as an extruder.