Abacus drive V0 & V1

Alternative gearbox


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I saw this great design by SRI International on hackaday for a gearbox and I had to figure out how the principle worked (see links).
Therefor I made the design. I haven't printed it yet but I plan to do so on my Ultimaker 3.
I'm not sure if it is patented but it is a very interesting design nevertheless :D.

Feel free to print it and comment, I would like to get this design working.


Revision log:
- It is designed to fit two 16*8*8 bearings to enable a smooth movement.
- Ofcourse I added the source files so feel free to make adjustments (sorry for the dirty modeling this time).

- Designed to fit two 16*8*8 bearings (one in the top and one in the bottom)
- Design changed to use 7x 8mm balls (because I had these lying around from an old bearing)
- Smaller (to print faster)
- Space between balls and housing increased (previous 0.3mm, now 0.4mm)

Materials and methods

PLA on it's own worked fine, 0.6mm nozzle is to big, prefer 0.4mm or even 0.25mm
Cura with normal settings, no brim and no support

None known yet, I think PLA and PVA will work out just fine



See all issues or open a new issue


5f8efd06e787e76aa3243c743c26c4bb?default=blank&size=40sfandersen added this to the misc collection ago
83e23c517188cdad269f3f36eacdcd41?default=blank&size=40Ethan Brush commented ago

Pretty sure this won't work like it's supposed to. This has 7 inner humps, 7 balls, and 7 outer humps. The one in the video has 6, 7, and 8, respectively, to create the gear ratio.

Mini 4040501Yi Luo added this to the gear collection ago
Mini  sushi chops trans more centeredSushi Desires added this to the Gears, Threads, Bearings, Pulleys, & Other Interfaces collection ago
Mini  sushi chops trans more centeredSushi Desires added this to the Mechanisms collection ago
Mini  sushi chops trans more centeredSushi Desires added this to the Upgrades collection ago
Fb6f8b283c1ac78dbcc5dd08c352744e?default=blank&size=40CybotixR printed this ago
Carousel thumb v1 a drive
Printed on:
SeeMeCNC - Rostock MAX Complete 3D Printer Kit
Had to scale it when importing into Fusion 360, otherwise did not match stated dimensions.
Marvin, I printed the V1 assembly out. Couple of issues, I belive that the main shaft should connect to the top inner support, otherwise, it just spins and spins around on the two bearings. The other issue is that the spacing seems to be a little wide to accommodate either 8 mm or 5/16" diam ball bearings. What I plan on doing is adding the main shaft to the top inner support and increase the diameter of the top inner support so that it lessens the gap between the main housing - I have ball bearings falling out!
84b0705343d374c365e96cc471ebe4e2?default=blank&size=40Alexander added this to the Gears collection ago
E38cb6e4da19b71e9c21298ed3643e41?default=blank&size=40Marvin Timmers published this design ago