Gear Bearing
Description
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.
Instructions
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.
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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.
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.
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?
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! http://www.thingiverse.com/thi...
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.
Thanks!
Joseph
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!
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.
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?
http://www.thingiverse.com/thi...
I printed another copy and made a video too... http://youtu.be/9g-x8fIbz-M
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.
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!
I finally got it printed at a tolerance of 0.2!
Here is a video that I took of it in action:
http://www.youtube.com/watch?v...
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.
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!
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.
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 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.
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.
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?
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
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! http://www.ustream.tv/channel/...
Awesome. This is the coolest bearing yet! Given how many bearings there are here, that's saying something!
Superb!
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.
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.
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.
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!
Awesome work!
I think that the issue with the customizer is due to a typo in the "np" parameter np=roiund(... )
Even i Opescad I'm just seeing a puck with the EL initials on it.
For some reason when I open this in customizer I'm seeing just a hockey puck no matter what settings I adjust.
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.
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!