Gear Bearing

by emmett, published

Gear Bearing by emmett Feb 23, 2013

Featured Thing!


The trouble with 3D printing a ball bearing is that spheres don't adhere to the 45 degree rule, so they tend to print poorly, or if metal balls are used instead, then the bearing requires assembly. This is a new kind of bearing that can only be manufactured by 3D printing and comes preassembled.

It is a planetary gearset and functions like a cross between a needle bearing and a thrust bearing. No cage is required to keep the rollers in place, because their gearing keeps them perfectly spaced. The gears are all herringbone, which is why it cannot be disassembled and also why it can act as a thrust bearing. If you're wondering how well a 3D printed bearing could work under load, please check out my video: youtu.be/ZghwSBiM0sU

This design is fully parametric and made to be adjusted in the Customizer app to whatever you need. Thanks to aubenc for finding a problem in the first version.

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hmm, would it be possible to create sinusoidal herringbone pattern instead of triangle ? it would allow smaller 'overhang'
hello everybody,
I have a problem. I have a lot of points or small filaments on my parts.
I thinks, I can't find good settings can you help me?
First off, I love this bearing! The possible applications are endless! Now, my question. What would it take to change the center hole from a hexagon to a circle? I dug through the source code, but I'm not skilled at all in coding, so I couldn't find it.

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The key to any bearing is the tolerance between the moving parts. Since this is printed all at once, you want the minimum tolerance possible, where any less would fuse the parts together. I print these with the MakerWare medium defaults on my Replicator 1 and it requires a fair bit of torque to break it free at first. It's designed to fit onto the standard English hex size for screwdriver bits, so you can use a tool to help turn it. Running it in a drill for a few minutes helps to smooth out the rotation.

You can adjust the tolerance in Customizer if you need. You can also change the dimensions, numbers of planets, numbers of teeth, etc. Normal gears use a small pressure angle in order to transmit torque, but here I use a large pressure angle so that they transmit force better (hence why they look more pointed than usual). Your chosen number of sun gear teeth is approximate because planetary gearboxes turn out to be quite constrained in terms of what tooth numbers will fit. See the beginning of my code for the equation I came up with.
hmm, would it be possible to create sinusoidal herringbone pattern instead of triangle ? it would allow smaller 'overhang'
hello everybody,
I have a problem. I have a lot of points or small filaments on my parts.
I thinks, I can't find good settings can you help me?
First off, I love this bearing! The possible applications are endless! Now, my question. What would it take to change the center hole from a hexagon to a circle? I dug through the source code, but I'm not skilled at all in coding, so I couldn't find it.
I printed one with a PrintrBot Simple Maker. 0.25 tolerance, half thick and size/1.5, 4 planets. My printer is yet not printing fully calibrated circles, so it moves, but not that smoothly (still it is amazing).
printed a couple of these on my 2x in abs but they're much too tight / melted to operate. i tried increasing layer tolerance to 0.3 and printing at 110% scale. any advice? how about a modified STL with smaller gears? :)
how do you all get this thing to work? mine was completely stuck, i broke it apart and the planets were fused to the outer ring like as if they were supposed to... can't break them apart with my hands. i made it in 0,2mm layer height in white PLA
Mine too. Maybe PLA isn't the right material for this.
By changing the tolerance to my layer height (0.3), I got it to work with my printrbot simple.
Good job, I like it !
These also make awesome wheels for toys!
Dumb question from a noob but, what part does this replace on the 8200?
This Thing(tm) is amazing ! the design is simply genious !
I printed it on my makerbot 2 in PLA with default settings in makerware. 10% infill, 2 shells, 200um layer height.
The clearance is perfect, i could gently loosen it, and after adding some WD40 and using it on a drill for a minute, it now runs very smooth.
Hi Emmet,
sorry but it doesn't work... the parts stick together.
How can I solve this problem?
go into customizer and increase the tolerance setting. that will increase the spacing between all of the parts. you might have to play with that setting a bit to get the perfect fit.
Hi atartanian.
Thanks!!!! Because of your help I made some nice gear bearings.
now a can also make other things that woudn't work for me.
i can not thank you enough!
Thanks for your help. I appreciate it !
I will try and let you know.
I finally got this working on my Printrbot jr. The problem was I was using Repetire-Host Mac 0.56 which comes with version 0.99 Slice3r. This version of Slice3r has a bug which attaches the small gears to the outer gear. I installed Slice3r V1.0 separately, changed preferences in Repetire to use the new Slice3r and now it works. I set fill density to 1 and Solid infill every 1 layers, combine infill every 1 layers, Extrusion multiplier .7
Excellent! This is the first successful object with moving parts that I have been able to print on my newly constructed Reprappro Omerod. Printing at a tolerance of 0.15mm I did not think would free up, so I tried it at 0.4mm which was too loose but worked straight away. Subsequently with a bit of persuasion freed up but was a bit bumpy. I'm now going for 0.24mm. Thank you for posting this Thing.
Stratasys just used this model to announce their objet500 connex3

Hey, awesome job on the design! I have a leapfrog creatr and was wondering if anyone had figured out the perfect customization settings for that printer???? Any help would be much appreciated
Hi, congratulations to this wunderfull design. I wanted to print it immediately when I saw it first time. I got the same problems like many others. Sticked together. Some time later I tested another slicer and had some very good results on other parts. When I tested the slicer with your gear, The first print was even to perfect! The gears where so lose, they nearly fell out. When turning the thing, they stuck because of to lose tolerance. I used customizer to adjust tollerance. But still the part was to lose. I was thinking that this happens because of shrink of my PLA. Therefore I made the hexagonal hole smaler, the tolerance even smaller 0.5 and the wall thinknes thicker. But now again, they stick together. I made another test but then the printer itselfe stuck while printing an fall on the part. Do you have a Idea if this may happened because of the customizing. Do you have a Idea why the first test with the new slicer where to lose?
didn't break free. :(
Sorry to ask something like this, but how can I remove the monogram. I am trying to print a very small bearing and the monogram is cutting in the wall.
Got it printed in Nylon, actually my mod of your gear. printed pretty well. Not as clean as abs, but still good. Nylon == major butt pain
I've been trying to print this in Nylon. Have you ever tried it? I'm having trouble with strings and blobs.
Awesome, first thing I printed on our new Replicator 2X - high res works out of the box!
Very nice model. I gave it a try today but unfortunately I'm afraid my printer's resolution is too low to print it in the original scale in such a way that it works properly. It took me quite a while to free all the parts so they could move and once I managed to do that, imperfections created so much friction that it is really hard to spin. I believe this would work much better if the model had some tolerances added.
It does have tolerances, and better yet, they're adjustable in Customizer. So widen them up and go to town! I make these adjustable because the printers are all so different it's impossible to make one design work properly on all.
I see. I will probably give it another go one of these days, then.
Made this on mt CUBE in PLA. Easy print! Planetaries were loose and working as I removed it from the print stage.

NICE!! Really like, THANKS!!!
I'm planning to print this on my new FlashForge (I've been a 3D printer for nearly THREE WHOLE DAYS now!). But given how slow the printing is, I'm wondering if anyone has a generic profile that might optimise my chance of printing one that goes round 'n round at the first go? I'm all for trial and error but less enthusiastic about re-inventing wheels!
Calibrate, calibrate, calibrate. Even two printers from the same company that ship at the same time could have subtle differences, and so too with the filament. Print out some test pieces and make sure you're all good, and then print out more tricky stuff. When you calibrate your machine well, and run slower to avoid wiggling your setup, the results are usually quite good on the first try -- but you have to get those calibrations done well first and foremost.
Many thanks - I'm discovering that the hard way! I also put the anti-vibration feet under my machine and it looks a bit like the Titanic at the moment of impact; this bothers me!
hi i have a question. i used slicer but found out that it presumes that the planets and teh inner and outer ring are one piece so i always have to crack it and that results in hard to turn gear. Any suggestions?
Yeah, if you scroll down there are lot of comments about this. The short answer is use a better slicer. Many are available.
I am trying this on my Afina Type H. This is quite brilliant. You have a gift for design. I look forward to your new ideas.
I'm an trying this on my Afina type H, 200um layer, high res. This is a brilliant design. I look forward to seeing how it turns out in an hour.
Go for it. This was designed in OpenSCAD, so what's available for download is my .scad file. It's just ASCII text. This is also what runs the Customizer app. I highly recommend you look into this free program, as you could easily make the modifications you're referring to there. I don't even know what a .par file is, and I have no ability to generate one.
What a gorgeous piece of design. Great to see that it's cc-by-sa.
Every time I try this (or anything requiring tolerance), the parts print fused solidly together. Can anyone recommend what profile settings I should tweak to make this work? I really like this and the adjustable wrench but I always end up with one solid piece on my Replicator
On my Replicator Dual I used the profile available to download in thingiverse.com/thing:23030 if you give it a try and the parts still fuse together, you can try to cheat and play with the filament diameter increasing the value in 0.05mm should make a big difference.
Awesome design emmett!

I'm going to buy a 3D printer in the coming months, and the first thing I plan on doing is using this design to create a stabilizer for my coffee grinder.

The key question is, how small can you print this? For example, could you print this with the outer diameter of the ring being 25 or 30mm?
The answer is "quite small", you can print it smaller than the sizes you are asking for. The diameter for this one thingiverse.com/make:25844 is 22mm
try it and tell us.
It is an incredible piece. I use it to explain the wonders of 3D printing to my friends. They have a hard time understanding the fact that is printed assembled.

Fantastic design. Kudos!
Well done Emmett! Just made it on my Flashforge Creator, and it works well.
Has anybody tried using this as an idler bearing on a printer?
My girlfriend likes this bearings very much as a decoration because of the aesthe...aests..., well they actually look good. I said, "hey, we will get you into this mechanical engineering thing. The mathematical side can wait." Next object I print will be a gearbox with a geneva wheel...
Awesome design! The success of these gear speaks for itself. That being said, does anyone have good/tight settings for printing this on a replicator2? I have printed 4 and each one seems to have the same problem. It rotates fine for the most part but then it reaches a point where it gets really tight and it takes alot more torque to finish the rotation, making it unusable for hobby-grade servos & track setups. I am more than sure that this issue is related to the print settings, but I have done enough wasteful experimenting with no workable results.

Current Setup -
RepG 40r22-sailfish w/ 7.5
Using Skeinforge(50)
Infill - 15
Layer Height - .27mm
Shells - 1
Feed - 80
Travel - 150
Temp - 235

Plastic/Extrude - 1.75/0.4
Try slowing down your prints. If you have backlash problems, you can develop high-spots. Try lowering your travel of 150 to 90.

Also, if you run the bearing long enough, even the high spots will tend to wear away -- you might just need to spin it for a an extra while.
Do you have any bevel gears? that are customizable how would you make these?
Check out the ancestor of this thing by GregFrost (above). His bevel gear library was what got me started on my cube gears. You'll have to learn a little OpenSCAD, but it's well worth the effort.
Thanks emmett i'm on that right now
very nice, but as with printing any pre-assembled moving parts, i'm concerned about calibration to get reasonable tolerance, seems like its generally always going to be a bit hit and miss, unless you can post-tighten.

for this bearing , have you considered doing something like making the outside ring slightly opened out, 'c' shaped, with a small gap, (and with the planet gears printed slightly further apart) so that after printing you close the gap, tightening the whole thing, which could then be held closed by a some sort of clip on the end, or just by whatever you mount the bearing into. (possibly a generic bearing holder or pipe clip.)
Have you tried? A lot of people have made it work (see the Made section). If you look back through the remixes, someone made an assemble-able version, so you could try that, though I'm not sure it's any easier.
No, i'm really thinking in a general sense and of pre-assembled systems, what i meant above is for there to be only a very small gap, not big enough to generally exploit for assembly, just to improve the tolerance without the chance of the parts being too stuck together. (although your bearing has set me thinking of specific uses).

there is also another possible way to achieve close tolerance; using tapering parts, so that they can be slightly displaced from their working position, and so more easily printed due to an increased gap, then finally moved into close spacing by some small more easily/externally accessible change.
Feature request: Can we get a checkbox to select a round hole in the center instead of a hex hole?
You're welcome to edit the OpenSCAD file. That would be a pretty simple change.
Great part and the customizer makes it a million times more useful. This part should definitely won the customizer competition (not just been a runner up). I'm guessing this part will be used in many many peoples designs as it works so well, so will be fun to see how other people put it to use in their models. Well done, and thaks for all your amazing work!
Finally able to print a geared object successfully, thanks to the Customizer! Read more on my blog: 3dgeni.us/customising-files-makes-it-possible-to-print-successfully-on-any-printer/
Just printed in PLA at 100% and I could not get it freed. After working at it for quite a while I managed to get the central gear loose, but I could not free the others. After smashing it with a hammer, I took a closer look...the other gears were welded tight against the outside and it took some more hits with the hammer to free a couple (which, of course, ruined them).
I just pulled my 608-sized variant off of the bed. It works like a charm, but this is DEFINITELY close to the small end for this part. I might try again with a smaller pressure angle - it seems like it needs 'deeper' teeth.Well done, emmett! This model is awesome.
mine was stuck at first but once i inserted a hex allen key and turned it to break the stringing away it moved then after playing with it for a while it got better and better, alos added in some wd40 for good measure! now i can spin it freely - hard to see how many rotations it does before it stops. love it!
Emmett, i'm an old guy thats seen a few too many of my inventions/designs "borrowed" by big companies and exploited for very big money. Please, do me a favour and get a US Provisional Patent submitted on this thing. Its huge. This is the type of thing that sets you up for retirement. Seriously.

I'm primarily an electronic guy with a few mechanical patents, but i would be happy to chat via email or text if you want.
There's this little thing called "prior art".

I'm sure there are others...
Yes, but is it additively manufactured? :) I realize emmett is not interested in a patent on this - but just for sake of the discussion, it should be pointed out that it might still be possible to get a patent on the use of 3d printing to print such gears. At a USPTO conference, it was pointed out that patents were issued in the early days of companies using LED's to replace light bulbs in various applications. Over time, LED replacements became "obvious" and no longer patentable - but the original ones stood.
Interesting post. I wonder if he ever made one?
I agree this is a great invention. But he already published it into the public. He can't PPA it after the fact. :(
He's got one year from public disclosure to file a provisional. Better to file first, but not required.
doesnt matter, China already is manufacturing it
Ooooh, I forgot that the US had the one year grace period. I had worked with some foreign patents a while back and got it into my head that any public disclosure was an instant disallowance. Yeah, a PPA would be good for him.
Thanks guys, but I didn't CC-license it to turn around and patent it. I'm already pretty sick of the patent system, and the last thing I need is to pay lawyers to help write and defend my own. And honestly, outside of the realm of 3D-printed plastic, I don't think it'll really compete with existing bearings anyway. At least this counts as prior art to keep anyone else from patenting it.
laird - in reply to emmett
Good point. Still, I expect this design to show up all over 3D printed designs, as the way it allows for printing preassembled is quite elegant.
OKay, Printed it today, thew print itself was a success, but I cannot het the bearings free. I am just one week into printing and I notice that my perimeters are maybe a bit too thick.

I have calibrated my machine so the dimensions it prints are almost a 100% correct, but the insides of circles keep on being to tight and also like with this bearing, the space between the herringboned dials in the bearing was so tightly printed that they are fused together. The hole in the center is now round because the hexagonal pin slipped from too much force put on the bearing to get it loose. I have cut out all residu from inside the bearing, beat it with a hammer, the middle wheel is free and can be wiggled very little, but it's free. The other wheels are all connected too much to the outer ring.

Slicing with Slic3r, what setting should I watch? Btw I think I printed this on 0.3mm I think. Maybe I should go for 0.4mm just as a test, but I don't know how to make the walls thinner somehow if that is possible in Slic3r. I am using it on a Mac so Skeinforge doesn't exist for me.

Printing it with Pronterface, works great.

Thanks for this awesome thing, wish I could learn how to print it better.
pretty awesome piece of engineering!
Anyone have suggestions for breaking it free before stripping the plastic from the middle opening? I've done 5 of these now, but cant seem to get it to not strip. Most have been .2 or .3mm resolution, 1 with .1m resolution, .25mm tolerances. PLA.
Every one of them was stripped. Should the print be done w/ 100% infill, or prepped to break open?
I think mine were 25% infill. One ABS, one PLA. No stripping problem, but the ABS was much tighter than the PLA. Still is, even after thousands of revolutions.
This and your derivatives are simply amazing, emmett. I am staggered that these are not featured, and instead makerbot is featuring its own useless designs.
As mentioned above, this illustrates not only individual brilliance, solving heaps of problems, but it opens up realms of new ideas to go off of or include it with.
I tip my hat to you. .o>
Because of your design i now have a mind full of ideas to put this to use and have already started on the first one, day two of design fest! thingiverse.com/thing:63231

So thank you, for the the tools and the inspiration
excellant work! printed nicely and I broke it free with a impact drill on low torque setting. very nicely done.
Finally got around to printing this today. Wow. Just wow. The print was a little stiff at first, but I couldn't stop fiddling with it in my hands. Just a few hours later, just from my manually turning it, it has turned into a freely spinning but still very well fitted bearing. This is awesome stuff.

emmett, first off, you're a genius, well done sir.

My personal objective with this file is to print 608z sized bearings x 8, and then stick them on my skateboard and see how they work.

8mm internal diameter, 22mm external diameter, 7mm thickness.

I don't have a printer yet though, so if someone wants to ship me the bearings, I'll post the videos of the test! LOL
You are a shoe in for the makerbot contest. The 2 best designs submitted (this and the heart box) are both yours. R U a wizard? Cuz dis iz magick to me! Yeah, you're light years ahead of anyone else on Thingiverse or any other 3d printing website for that matter. There are other beautiful designs in the universe but no designs that show a mastery of the limitations and promise of 3d printing. You somehow always manage to design something that sidesteps 3d printing's limitations while maximizing 3d printing's strengths. All your designs are deceptively simple to the casual observer, but to those in the know it evokes wonderment because of the complex thought that went into designing it so that a symphony of complexity comes together in a seemingly simple operation. If intelligence is the ability to make something complex simple, then your I.Q. must be off the charts!
Thank you, I think that's the best complement I've received.
Don't forget to put a drop of oil in it! Makes quite a difference.
Cute, but the forces require a drill motor with 1/16 hp or greater to be useful. A balance between PLA exclusive and bearings would be much more useful.
Have you printed one? With the right tolerance, they spin quite freely. I agree it's not as smooth as one machined out of steel, but I'm not sure where your 1/16 hp number comes from.
I think you have recreated the wheel for the 3D printing revolution. Awesome job.
are you FREAKING kidding me? This might be the most AWESOME thing on Thingiverse!
Emmett, did you know about GregFrosts involute gear library?
Yes, in fact I put his as the ancestor of this thing. I've used his library extensively, but now I'm working on a more general version, which this scad file is the beginning of.
Ah, I see.
I printed another copy and made a video too... youtu.be/9g-x8fIbz-M
It should ofcourse be named "cogbearing".
You are genius sir!
Now THAT is how you do it! Excellent work, as always!
20,000 RPM Test!! Taking my ABS Gear Bearing to 20,000 RPMs, held up awesome!

So I ran a test today on my newly printed ABS Gear Bearing, Ran it on a pneumatic grinder with roughly 20,000 RPMs. Held up quite well!

This is really cool!

What's the turn friction like? I would imagine gears have a lot of friction...
Gears have friction where they touch (the teeth mesh) but they also rotate. The elegance of this design is that it provides a freely rotating bearing without requiring anything to slip - the planet gears rotate, allowing the outer gear to move freely around the sun gear.
Actually the whole point of gears is to have little friction; it has a lot more to do with the accuracy of the printing than the design. See scubaru89's video above.
Imma have to redesign /thing:37432
Great work! This is a huge break through for us as a community. We now have the ability to make amazing new inventions. U DA MAN!!!
Printed this today on a Dimension 1200, came out awesome, as soon as I popped it off the support layer it began to spin. I do have a little play in the gears but that is most likely from the Dimension being able to produce higher quality prints that don't need as much a wide tolerance between gears. I love this little thing!
Coooooooooooooooooooooooooooooooooo ooooooooooooooooooooooooool
could someone upload gcode for the one pictured?
I finally got it printed at a tolerance of 0.2!
Here is a video that I took of it in action:
bravo sir. I can't wait to see what people make using this!
I made one. It sliced and printed flawlessly. I can't break it free though. I've tried using tools and a ton of brute force. It won't turn. I had no idea what to set for the tolerance setting but I'm guessing .15 won't work for my printer. I'll try again with a bigger number. Wish me luck!
I ended up using a cordless drill on low setting to get mine started. I just used a bit that fit perfectly in the center hole and pressed the button. It spun free immediately and was able to withstand the drill on high power.
I thought mine was stuck for good too. The thing is, when you break it, it will break along the lines of the gears and will free itself. I had to use a socket wrench with the hex attachment in the middle and a giant pair of vise grips on the large outer circle.
This is a very cool design and concept! :D
I think this is awesome, on my 3rd attempt to print. Slic3r can't handle slicing this thing. It is connecting the gears to the body on some of the layers. Any chance you could add your post-sliced g-code of the main version to the downloads? I want to compare it with the slices I am getting. Thanks!
Which settings did you use for sucessfully print it with slic3r?
I got it to print the standard one using no perimeters, but was able to print a perimetered bearing by adjusting the spacing to be 2.5 in the customizer.
I think you can use 'split' in the slic3r gui/plater then it will keep the parts separate. I've not tested this with a print yet but the gcode looks right now.
ramai - in reply to ramai
Okay, so for anyone else using slic3r, I got it to slice by using no perimeters. It ain't pretty, and it ain't smooth, but I printed it, and it rolls. I'll post a photo in a bit. I bet it would roll a lot smoother if I had 1 or 2 perimeters on there.
If you use the scad file and set the tolerance to .2 instead of the default .15 and leave everything else the same slicer will slice it just fine. I sliced and examined gcode at .16, .17, .18 and .19 before I got to .20 and slicer not linking some of the planets to the outer rings.
So I sliced it using .20 at a layer height of .4 and 2 perimeters, there were still a number of connections. Changed the layer height to .2 and there were still 3 or 4 layers that were connected. Sliced it at .15 layer height, and still 1 connection on the 12th layer. Slicing at .1 produced even more connections. Attempted with 1 perimeter as well. Can't get it to go without connections. How'd you do it?
Listen to this guy! I'm going to try printing it at 0.20 tolerance when I get home and post my results.
I rendered with "tolerance" of 0.15, 0.4 and 0.3, and 0.3 worked well. 0.15 ended up permanently bonded, while 0.3 popped loose with an easy twist of a screwdriver. I'll try 0.25 and 0.2 tonight.
ramai - in reply to laird
I printed one with 1 perimeter at .25 tolerance, and I got a successful print out of it. 0.25 was the key for me. 0.2 was still bonding and 0.25 was snug but separate. Printrbot Jr.
If it is sticking for you, just throw it into the microwave for two minutes and twist it with an Allen wrench or something. it cleans it up quite well.
macegr - in reply to Barz3
For PLA, reduce that to two seconds...I use a hair dryer or hot water and get them warm, then spin with a drill until it cools down a bit. I think Emmett's several minutes of drill spinning just heat up the gears enough to deform. With hot water I can get pull these off the print bed and get them spinning smoothly in 30 seconds.
When I sliced it with slic3r, the outer gears fused to the ring. I printed it at a layer height of 0.15 and couldn't get it to budge using a flat head screwdriver. I ended up breaking it with a mallet.
Is it like the picture woodsmoke posted? If so, it sounds like slic3r has a bug that should probably be reported. I used the makerbot slicer in MakerWare and it worked well.
My first thought was that this would make a great substitute bearing for a filament roller (printing 4x of them, printing vertical supports to hang them on and setting a spool on them), and I think that a slight groove option/v-shaped indent in the outer surface would be a great addition. I just can't seem to win when it comes to open scad. Would anyone have any suggestions on how we could make that change?
Don't give up on OpenSCAD; it's really not that hard if you give it a chance. Just open my file and start putting # in front of subobjects to see how they interact. Your change will actually be pretty simple.
Emmett, You've done it again!

I printed the 6 planet one right off, and it came out quite well.

I have a request / suggestion for a modification if someone wants to take it on (I'm not Scad literate): place an axle thru hole in the planets. Doing so would make it possible to attach a cage from which an input or output can be driven.

I tried a custom one but ran into colliding planets. See settings below.
w = 8
P = 45
T = 15
D = 76
number_of_teeth_on_planets = 8
number_of_planets = 6
tol = 0.15
approximate_number_of_teeth_on_sun = 9
nTwist = 1
emmett - in reply to TSDF
Yeah, it's parametric, but you still have to apply some critical thought. If the planets overlap use more teeth on the sun gear until it looks good. Remember, number of teeth is proportional to diameter.

As for holes in the planets, that's an easy mod. Just download my scad file and difference a cylinder from the planets. It's high time to learn a little scad!
Awesome! Loved the detailed youtube vid. It's indeed rolling much better than the printed ball bearings ;)
This is a cool print. I made one the other night (The 5 planet one) that was pre-rendered. It was a little tight so I guess next one needs some looser tolerance on my ToM. Awesome!
Imagine Emmett with and industrial 3D printer, it would be dangerous.
Yet another awesome model!
You're a credit to Thingiverse
Thank you for publishing this great idea under an OpenSource licence! This bearing will help us to develop totally new 3D printed machines.
I thought you did some amazing work before, but this is on another level imo. So inspiring.
Excellent! This print is begging for a Nylon and Polycarbonate dual extrusion test
Streaming a live print of this now. Hope it spins! ustream.tv/channel/macegr
Awesome. This is the coolest bearing yet! Given how many bearings there are here, that's saying something!
The like button seems inadequate. I need a mind blown button!
QFT! Awesome idea emmet!
Something similar was on my todo list.
I thought about a drive for a moineau pump via a planetary transmission (after a wobble compensation coupling of some sort) There you see quite naturally that with herringbone gears you could take care of the axial load too. But for a transmission the planets themselves need to be beared. Now that I think of it, why not bear the planets of a big planetary gear transmission with small ones of these.

Printability in one piece is cool and saves some assembly work. I like the minimalistic design removing everything but the core functionality leaving only an irreducible minimal machine element.

Judging from the video your GearBearing is lash free. Still I think a version with minimal post assembly could work even better. You buy this at the expense of part size assembly time though. When the outer ring is split in two mirror symmetric rings (which bolt or/and screw together) all parts can be printed separately. Then clearances can be made even tighter and there are no stringing travell moves.
I'm impressed with how smoothly this turns, and the amount of force it seems to be able to take. This strikes me as something which could actually replace metal bearings in some light-duty applications.
Yes - especially if printed in nylon...
Very cool....I get hokey puck when I change away from default as well. I can get it CGAL to render with .17 and .18, and since I was able to successfully print at .15, but was only able to free the center gear, I'll try .18 and see how it goes.
Hmm, I thought I fixed that. Are you using my latest file? It seems to be working in Customizer now, have you tried that?
It pucks for me in Customizer as well (put in 0.20 to see this). I grabbed the SCAD file last night, so if you've updated it since then, I wouldn't have the latest file. Either way, .15 is a good place to start. Mine would have likely been fine if the bottom hadn't squashed so much and if I had modified the hex key insert to take something I have lying around, rather than stripping it out. This go-around I expect success.
Emmett. I bow down before your awesomeness. Two questions.

1) Is it PLA compatible. My guess is that it gets quite warm and PLA is not known for liking that
2) What about plastic fuse? Do you need to lubricate it at all?
I had no luck with turning with my Clear PLA, although I printed it at 0.2 line thickness. Ill try at 0.1 next :)
I print everything in PLA, so yes, but I'm not promising it'll run at 3000RPM. I haven't lubricated mine at all and they work fine (as you can see in the video). It probably wouldn't hurt, but since gears mostly roll rather than slide, it shouldn't make a huge difference.
Printer AWAY! .... thanks for the info.
Your creations are always so awesome, makes me wonder what im doing with my life.

good work man. Printing now.
Emmett.... you are a genius. It takes some very legitimate outside-the-box thinking to come up with something like this. Bravo!
Bravo indeed! Simply brilliant!
I second that. Bravo!
Thanks! To me, 3D printing is one of the most deserving reasons for out-of-the-box thinking to come along in a long time. So much is possible now that never was before. I only hope I can help to inspire others.
It's so nice to see the medium of FFF 3d printing utilized to its strengths! You, Sir, are a pioneer, and I salute you.
Impressive... printing it right now :)
Awesome work!

I think that the issue with the customizer is due to a typo in the "np" parameter np=roiund(... )
You nailed it that typo is what is causing the problem. I was able to export the script and change that thing and now it is working for me.
Ah, so simple. Can't believe I didn't catch that. Must have forgotten to hit F5 the last time. It's fixed so it works in Customizer now. Thanks.
It looks good in customizer now but when I open up the resulting stl it is still a hockey puck for some reason. The only thing I modified was the tolerance to 2.5 from 1.5.
Default is 0.15, so try 0.25. 2.5 would be an aweful lot.
Oops sorry I meant .25 I'm trying .20 now to see if that works.
Hmm, I see what you mean. It renders, but doesn't make the right STL. Perhaps we found a customizer bug after all.
Ah, nope it's an OpenSCAD bug. For some reason with tol=0.25 it throws a CGAL error and gives up on the gears. I guess just try a slightly different number and hope. I'll try and figure out if it's because of something I did.
I imported your OpenSCAD script and put the value at .23 and it compiled and I was able to export it to stl. I'll give it a shot on the printer as soon as it is available.
Okay, looks like it was a roundoff error (OpenSCAD's one true failing...). After some minor changes, it appears to be a lot more stable now. Hopefully no more solid cylinders anymore.
Excellent I'll give it another shot. Thanks for designing such a cool thing.
Even i Opescad I'm just seeing a puck with the EL initials on it.
Emmet, you are the master, we are but unworthy students!
For some reason when I open this in customizer I'm seeing just a hockey puck no matter what settings I adjust.
Increase the "tolerance". I had that trouble, but when I went to 0.2 or higher, it worked fine.
Emmett fixed the problem for me. It was an scad rounding error. I've been able to print a few more copies that have worked very nice.
Awesome design! I'll have to give it a go. I've been tinkering with a few bearing designs as well but have struggled with making them parametric, I'll poke around your openscad file to see if I can't pick up some tips.