Gearbox DIY (4,5:1)


unfortunately, I can’t upload files in the post.
But here is a link to my dropbox to view and download the list of materials and the files.

Gearbox DIY 4,5:1 downloads

Best regards


Thank you so much. Son and I will try to print it this w/e.
Would you please name the ball bearings you recommend ?

By looking at the stainless steel ball bearings with the dimensions you kindly provided, there are still a few to choose from …

No problem, I’ve added the order numbers to the list of materials.

Best regards


Last one 2d-foiler :slight_smile :

Would you be so nice as to upload all the pieces you have on the picture ? It will be super fun to play with everything for a school project.

I just wanted to mention, that the sales rep from Neugart told ne that the speed limit of 8000rpm is because of the journal bearings they used. Ball besrings could run faster apparently.

The step files of the pinions can be downloaded direct from
But I don’t know if they really work or if they are more symbolic.
If you need something else too, let me know.

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They do work. I’ve been using them to prototype my gear box.


@2D-Foiler how do you order stuff from . I wanna buy gears but I can’t figure out how.

Go to “Anmelden”, then to “registrieren” or
change the language to english, then go to “sign in”, and “register”

Hm cant find that anywhere… Anyone know any sources for gears in Canada (any anywhere North America)?

McMaster Car. 123456789

They don’t have metric gears

Hey guys. I am huge fan of this webside from Czech Rebublic. Does anybody tried to use the planetary gear box from the battery drill or screw-driver? I am not sure about the gear ratio. I must calculate it.

I was thinking the same and did a bit of research on the net. It seems that most gears have higher ratios than we need. Nevertheless there are so many different kinds of drills and electric screw drivers, maybe you find a spare part that fits for a propulsion system.

I have a drill planetary that I thought about trying out but I could only get 3:1 or about 20:1 depending on how I broke up the sets. Don’t think its that great of an option.

I don’t know if these are any good, but just read about them on the ebike forum. Someone recommended them for use on the 80-100 motor.
GAM gear Reducer
Aother option if you can’t find a Neugart or similar.

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I’m testing out a mostly 3d printed gear box inspired by @2D-Foiler s. Likely it’s going to fail but so I’m pretty hopefully

Looking for advice on how to drill through my prop shaft if anyone can give me tips.

We did this a while back. Using a drilling rig. First make a small flat spot on the axle then insert it into the rig and drill. The rig we used was made form steel but I think a 3D printed one will also work.


If you have bought a linear shaft from China it is likely that it’s to tough to drill through. Not even an engineering shop could drill mine. I ended up using a stainless steel shaft instead.

It’s a Chrome Steel rod not hardened steel linear rail.

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