Loading
Hey! This thing is still a Work in Progress. Files, instructions, and other stuff might change!

Nema17 Differential Planetary Gear

by SimCity, published

Nema17 Differential Planetary Gear by SimCity Mar 9, 2013

Description

UPDATE: There is something coming for this but I just got a new apartment so all spare time is going into moving.

So I decided to put emmetts differential planetary gear on a nema17... I wonder what we could do with that now? (answer is coming)

Ripped the code from gregs x-ends, adjusted ratios and size to get a fairly decent gear that should be printable and fit between the mounting holes of a nema17 and mashed them together. This is the result. yet to print it but its all scad code so fairly simple to modify.

Too hot to fire up printer atm, air con is struggling as it is. So yet to test this.

NOTE: no linkages yet so still has the hex hole in the center so if you can find a hex nut with a work in the side that fits use that. otherwise wait or come up wiht your own.

Recent Comments

view all
While this would be no use for the axes on your 3D printer (due to minimum extrusion speed), it would be amazingly useful for the main spindle on an eggbot. The torque multiplication may even add enough strength to use it as a lathe. I only have an old 3 deg/step motor on hand to build one for my hackerspace and have been putting it off since the resolution would be too poor. If this prints decently it'll be worth making now.
depends on how low you can get with the tolerance. Honestly though my rep rap is currently at 3200 steps per mm without any gearing, using this to gear it down further would be 185600. it would take forever to move the z axis... that and its so fine you would never use it, cause you cant drop the flow rate of the extruder beyond a certain point
Do you think this homeprinted gears would be precise enough to make the z-axis steps on a reprap type printer smaller?

More from Parts

view more

Liked By

view all

Give a Shout Out

If you print this Thing and display it in public proudly give attribution by printing and displaying this tag. Print Thing Tag

Instructions

print the parts put spacer in if needed (most steppers have a raised bit in the center that needs to be cleared) bolt it on. Wont drive as is yet as still designing the linkages.

While this would be no use for the axes on your 3D printer (due to minimum extrusion speed), it would be amazingly useful for the main spindle on an eggbot. The torque multiplication may even add enough strength to use it as a lathe. I only have an old 3 deg/step motor on hand to build one for my hackerspace and have been putting it off since the resolution would be too poor. If this prints decently it'll be worth making now.
Do you think this homeprinted gears would be precise enough to make the z-axis steps on a reprap type printer smaller?
depends on how low you can get with the tolerance. Honestly though my rep rap is currently at 3200 steps per mm without any gearing, using this to gear it down further would be 185600. it would take forever to move the z axis... that and its so fine you would never use it, cause you cant drop the flow rate of the extruder beyond a certain point
This looks great -- I was looking for a way to achieve gear reduction in a small package for a stepper (trying to build an improved bowden extruder). One thing I noticed -- I don't think this is going to work without a fixed planet carrier, as the planets will simply spin around instead of rotating the output shaft. That said, it should be quite simple to make one.
That said i'm printing one right now and I'll try a few things with it once it's done.
Top