Extruder Gear Clock - True 12:1 Ratio by LankRC

Last crawled date: 3 years, 4 months ago

This is a true 12:1 ratio extruder motor indicator! The main gear is attached to your extruder motor with a simple 8x3mm magnet, and as your extruder turns, the arms on this will spin like a real clock.
Gears were created using Gear Generator, here is a link to these specific gears: https://bit.ly/30b5ygY
See it in action here: https://www.youtube.com/watch?v=5CABNrKxzU4
This was printed with a 0.4mm nozzle at a 0.2mm resolution, but this might work better with a smaller diameter as the tolerances are fairly tight. Print this SLOW!! If there are any imperfections on the teeth, the gears will tend to get slightly stuck and you won't get a smooth motion.
Assembly is easy!

On the holder, insert a piece of filament into the small hole on the right side on the opposite face of the clips. This will serve as the shaft the secondary gear will rotate around. It should fit snugly. Try to keep the filament as straight as possible, and leave a little extra, we'll trim it later.


On the primary gear, press an 8x3mm neodymium magnet into the space. It should fit snugly. I used these: https://amzn.to/2HAms2f


Attach a second magnet to the first.


On the other side of the primary gear press another piece of filament into the hole. This one should fit snugly as well. Keep the filament as straight as possible, and leave extra, we'll trim later.


Take the primary gear and place it into the hole on the holder. The magnets should be on the same side as the holder clips.


Slide the secondary gear onto the filament attached to the holder with the smaller gear facing down.


Slide the arm with the gear on it onto the filament from the primary gear with the gears facing down.


Trim the primary gear filament, leaving 2-3mm of filament exposed.


Press fit the fixed arm onto the primary gear filament. This should fit snugly so it turns at the same rate as the primary gear. Try to keep the two arms parallel, so they don't collide with each other while spinning.


Trim the secondary gear filament close to the face, leaving just a little bit of filament exposed.


Use some pliers to flatten out the end of the filament so that the secondary gear won't slide off.


Take the whole assembly and attach it to your extruder with the secondary gear on the right.

Fire up the printer and enjoy!