Loading

Cube Gears

by emmett, published

Cube Gears by emmett Feb 3, 2011

Featured Thing!

Description

UPDATE: This design has been superseded by my newest version, thingiverse.com/thing:213946, which is all printed and snaps together.
***
This started out as an exercise in using Greg Frost's awesome involute bevel gear script thingiverse.com/thing:3575, but turned into a rather pleasing worry-ball type thing. It's also clearly influenced by Greg's broken heart thingiverse.com/thing:4683, though this has octahedral gears rather than dodecahedral, so they all mesh with each other and spin. My favorite thing about it is that you can grab two opposite gears and twist them, making the center with the other six gears spin rapidly around.

Recent Comments

view all
We just put one of these together, and painted it. This is a delightful little gadget, thank you for posting it!
You should make little pieces that you can glue on the ends with the screws so that it looks like a full cube.... Or maybe i'll do it...
Great print! I had some troubles slicing the center with slicer but after esporting again the stl from de scad allways gone fine

More from Interactive Art

view more

Liked By

view all

License

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 list. I used a stock TOM, printing raftless with zero fill (just a couple extra shells). Skeinforge 35 made some odd slicing decisions, but it didn't affect the outside of the parts. These are good parts to convince you your calibrated printer still needs some tweaking.

Use a screw to tap threads into the center block first, because it makes it easier to assemble. No glue needed, the screws should stay tightly in the center block while the gears revolve. Attach the gears, making sure the edges of the cube connect them. If the gears are too tight to spin easily, just unscrew them all a millimeter or two.

The OpenSCAD file is highly parameterized to allow easy tweaking (for different proportions, screw sizes, etc.). You can also change the ratio of teeth on the gears, but you'll need to put the desired parameters into gearopt.m and run in Matlab (or Octave) and copy the result into the OpenSCAD file. This is necessary because I couldn't solve the geometry with anything but an iteration loop, which OpenSCAD doesn't handle so well. I used the MCAD library for Greg's involute gears github.com/elmom/MCAD.
We just put one of these together, and painted it. This is a delightful little gadget, thank you for posting it!
You should make little pieces that you can glue on the ends with the screws so that it looks like a full cube.... Or maybe i'll do it...
Great print! I had some troubles slicing the center with slicer but after esporting again the stl from de scad allways gone fine
Really love this print! I wanted to let you know that my wife, who is a social worker, is going to use our first print in her office for patients. She thinks they will be very therapeutic for kids.
Thanks! I'm glad to hear math and makerbotting are coming together to help the children.
This thing is GREAT and is my new favorite thing to show people. Thanks for making it!

Hmm, I do have a question though:

How would one stop the gears from curling up during printing?? I mean, I have printed two and they work, I would just like it to look a little neater. Seem to curl up, which makes the layer beneath the current layer not be there, so then I have some hanging threa
ds and a lot of slop.
Thanks, I'm glad you like it. I've had some trouble with curling as well. First, I'd recommend printing on kapton tape (ABS sticks to it really well). Second, printing it hollow helps to reduce the warping stress that pulls up on the corners. If SkeinForge is putting in weird diaphragms, get the very latest version (not in RepG yet). It might also help to use Multiply to print four gears at once so there's more cooling time for the layers.
Yes, I am already printing four gears at once. I have a kapton film platform, it's super sticky. The first layer is fine, sticks perfectly. I also have solidity set to 0, just like it says in your instructions. Problem is, as layers start building up, the corners of the gear teeth that stick out into air are curling up. It still prints and functions, but the gear teeth will curl, and then the next layer placed on top of the curled layer below it, will just flop down, because there is nothing there to support it any more.
Have you tried Bre's calibration method? blog.makerbot.com/2010/12/22/calculating-your-feedrate-to-get-awesome-prints/

A little cooling air might help too. I think this is a common problem, just often not noticeable until printing a complex object like this.
Yeah, I designed a fan bracket, printed it and attached a fan to my ToM:

thingiverse.com/thing:6787

It was only a matter of airflow. But I sure as hell wasn't going to sit there and blow on it for many hours.

Observe the photo! Black gears show without fan, Blue gears show with fan.
I finally made one on my Ultimaker, this is a really awesome item!! youtube.com/watch?v=aqJjLIBQax0

You have the right to be seriously flattr'd 8-)
It has a very nice design, and is looks very good, but the gears don't fit together quite right which makes problems when spinning. But otherwise, it is quite nice. Maybe the smaller gears should be a bit bigger? Also the tightness of the screws is a bit finicky. But still, it's very good.
JohnA - in reply to Guest
Mine spins great?
Looks like a good starting point for a Gear-Cube type puzzle. Gearing action is mesmerizing.
Very Nice. 6-32 1/2" screws can be used.
youtube.com/watch?v=4F71XHbB2fQ

Had to show it off, I love this thing :)
Thanks for the video; I'm glad you like it.
I would like to see some little pyramids added to this to glue on the corners so you can

1. hide the screws and

2. have a actual cube.

It looks great. Either way its on my print list.
That's a pretty serious overhang on gear1. Ended up needing to use a fan with it. Other than that, printed fine.
Yeah, the planar overhang isn't bad, but right at the tip it goes pretty far. I had trouble with warping even though it stuck perfectly to my paper/kapton belt. On the plus side, the warping tends to shrink the gears, so it often doesn't interfere with their meshing.
With a fan, even those came out no problem. It will put extra load on your platform though.
Printing one now. What kind of bolts/screws did you use? Probably going to just use what I can dig up, but thought I'd ask.
emmett - in reply to bre
M3x20, on the parts list below (extras from the TOM kit). I'm sure you can substitute 1/8" if you want to go english. You might also have to adjust the scad file for your printer or drill out the holes a little. I have yet to experiment with the stretch module.
I got to see this first hand at our January Seattle Makerbot Meet-up. It was Pretty cool.... though I thought that one was printed in white?
yeah I saw it there too, it was white. but the black one looks even better. nick work Emmett
Thanks, it was nice meeting you both. Yes, white was version 1.0, this is better. Are there any more Seattle makerbot get-togethers planned?
Top