3D Printed Planetary Cycloidal Hub Gearbox. How far can it drive?

[@michaelrechtin]

Get the exclusive NordVPN deal here at nordvpn.com/michaelrechtin. It's risk-free with NordVPN's 30-day money-back guarantee!

[@l0I0I0I0]

Michael, would this be good for turning a possibly heavy solar panel 360 deg? I'm trying to build a solar array and need precise measurements, and it will of course be in the sun for 30 years.

[@reizinhodojogo3956]

not hating but did they pay u?

[@l0I0I0I0]

@@reizinhodojogo3956 Nord is probably giving him some comp but it's understandable as it's hard to work for free.

[@Thoran666]

Nice gearbox Micheal. To test the gearbox further just let it drag some weight while doint it's rounds.

[@LecherousCthulhu]

You could just print a second tire and use them to hold up a platform that you can then place weights on. You can then use both gearboxes that you have printed in order to determine wear and condition changes over the same period while applying load to the gear boxes. This will allow an expansion of your testing because you can slowly expand this out into a small automobile with actual wheels for road testing

[@theoldknowledge6778]

Best 3D printed reduction I've seen so far on KZbin! It looks like there's almost no backlash!!! Nice work

[@TheStuartstardust]

4:10 - not exactly backlash, but alignment of spur gear seems to be important to ensure even loads. And with this, biggest amount of backlash. Is it back driveable? 🤔 Anyway - cool project, super nice of him to release files 👍😎

[@L0615T1C]

@@TheStuartstardust That was before the 2nd cycloidal drive was installed

[@robertchristmas7050]

​@@TheStuartstardust

[@MegaCadr]

Who knew you could design gear boxes in fusion 360 so quickly? Awesome video!

[@BloodyMobile]

Engineer's version of "How to draw an owl" "Step 1: draw some circles" "Step 2: draw the rest of the fucking owl"

[@Eluderatnight]

@@BloodyMobile if they write a patent like that then its free realestate.

[@darkshadowsx5949]

I thought i was quick at designing in fusion 360. this guy is legendary.

[@badbabyboyo9593]

There are a couple of good gear building extensions for fusion 360. Idk if he used those but they are worth checking out

[@BloodyMobile]

@@badbabyboyo9593 FreeCAD also has some, including some specialized for cycloidals.

[@MatrixRay19]

Nice video man! Just a couple of things: 1. I'm pretty sure that tire tread should be run on the opposite direction(CCW instead of CW), 2. Ideally for 3D printed parts you want heat set inserts that look like herringbone gears instead of the flat ones you used, this makes so they don't slip out later. CNC Kitchen has a great video on this topic.

[@evanbarnes9984]

Glad I'm not the only one who noticed the tire was being run backwards! It was driving me nuts

[@ye1o881]

@@evanbarnes9984 i saw that too but thought "no, he made the thing, he knows best." Glad to see im not crazy.

[@theboz1419]

Ok, I wasn't seeing things weird again. that's a relief.

[@CorDawgYT]

Also I've printed tires with TPU and they turn out amazing, something to think about.

[@ronnetgrazer362]

Came here to bitch about the inserts. These are for injection modling, you want the "knurled" type. Having said that... GREAT introduction of yet another cool gearbox for makers!

[@mrnlce7939]

Hate to be that guy but your tyre is on backwards. Currently the treads are pushing the muck and water in to the middle when it should be pushing it out to the side.

[@benblank609]

Thank you for being that guy.

[@ChristoffleGrange]

I came to comment this. It made me OCD go crazy.

[@EALordBaal]

Yeah lol it was bugging me also

[@straba3976]

Wouldn’t you have less grip and less movement/power efficiency ?

[@mrnlce7939]

You would have more grip. I don't know about efficiency as there would be more friction. also there would be a deeper trench as all the loose mud would be pushed to the side.@@straba3976

[@avaviel]

I watched your fusion 360 tutorial at 0:40 , I know nothing about cad, and now I'm working for an engineering firm making literal boat loads of money. Thanks Michael!

[@OMGWTFBBQSHEEP]

Please do dynamic load testing! Make a Ø100 mm drum instead of that wheel, and attach a string with some weights. Then you can have a program making it spool in and out repedetly. Would be really intersting to see how it holds up. Great vid btw!

[@michaelrechtin]

Will be doing something similar to this soon. Stay tuned!

[@freman]

test carried weight and towed weight.

[@themadscientistkk]

@@michaelrechtin Or maybe just a wide rake for inside the circle

[@noahmiller794]

YES I was just going to comment thid

[@adamthedog1]

@@michaelrechtin I'd also love to see the wear on the gearbox as a result of heavy radial load! maybe suspending the gearbox horizontally with a drum with weights in it or somethjng similar. as the drum rotates, the motor should always experience approx full overhung load. part of me wonders how much the rigidity of this gearbox (each shaft looks to be pretty sturdy) will negate the danger of a radial load or what

[@soybeanfarmer4576]

Great video! As a farmer I noticed the tire/rim was mounted the wrong way. Tread design is for reverse direction. Productive video. 2 thumbs up.

[@mocmaniac1571]

I would love to see the same test under some load ! But man this is a really good starting point !!! I think having slow moving parts keeps them cold, especially pla/pla+ that melts at low temperature and thus limits wear. Plastics can last very long but as soon as the become hot they disintegrate really fast

[@NigelTolley]

I've heard tell that 3D printed plastic will melt.

[@josephpk4878]

That circle extrusion into a gearbox was priceless - it helped me to understand why my clients are always confused about how long it takes to model something.

[@gianlucasini612]

Nice gear - couple of additional tests / improvement: 1. Add weight to the wheel. 2. Check where the dirt is entering: motor side. 3. Make it near waterproof on external: you can add a a plate to the external side and make it sealed, with an o-ring.

[@oldtimefarmboy617]

Just for your information, the tread design on that tire is suppose to be the reverse of how you have it rotating. Where the two lugs overlap in the center should be pointed in the direction of rotation. Sort of like an arrow that points where you are suppose to go. While not important for what you were doing with it, if it was on a vehicle pulling a load and the wheels started to slip for any reason, it would allow the soil to be pushed off to the side rather than generate enough pressure to damage or break the lugs off.

[@Schradermusic]

If you want less rolling resistance, you are right. But with the direction he chose, you get more traction.

[@oldtimefarmboy617]

@@Schradermusic Actually, it has been proven to be just the opposite. If you are traveling, it does not matter what direction they are pointed, your rolling resistance will be the same. But go out to a farm and look at the tires on the equipment or to a construction site with rubber tired equipment and all of the equipment designed to pull implements that require maximum traction will always have the chevrons on the rubber tires with the point in the direction of travel when pulling a plow or a ripper through the soil and they need the greatest traction.

[@ExcessiveOverkill]

Sweet, cool to see how well everything held up. Those RV reducers are what are used in pretty much all large industrial robots. I suspect you could get crazy amounts of torque out of it before it breaks.

[@sprovost69]

Being the son of a farmer, I noticed you were running the tractor wheel backward… This is why the threads are filling with mud. If you run it in the other direction it would self clean, keeping the traction.

[@Nifty-Stuff]

Wow! Great job on this gearbox video! I LOVE your combo of great info, design, video, and humor! PLEASE keep making awesome videos like this!!!

[@JohnLauerGplus]

Nice work. Yeah, I'd love to see this hooked up to a BLDC. You can use SimpleFOC to drive the BLDC. I'd like to see some load tests on it too. I also keep wondering if you get faster/slower fits and starts as it moves along those cams? It seems like I see a bit of fits and starts in the video rather than truly smooth rotation. It may not matter for the application, but a robot arm may have issues with that. If it's just used for wheels on a rover then probably fine.

[@ProlificInvention]

I made a spinning plant platform in my back yard this last year and spun a special plant at 30 RPM for 7 months which was approximately 9 Million rotations. My platform was driven by an old 14.4 volt DeWalt drill hooked to a variable 0-48v power supply set at about 4 volts: direct driving a "Lazy Suzan" type platform with metal bearings, a scooter wheel with a solid shaft bolted in and chucked into the drill was my drive wheel that transferred power. It was a fun project and I was reminded of this by your video. Perhaps you could make spinning plant platforms, it's a fun experiment that is endlessly customizable and it turned out to have fantastic results and increased growth as well as pest resistance, and cold resistance when the time came.

[@Sabe-Stormrage]

For a gearbox that's almost completely plastic gotta say it's impressive that nothing broke after 2 weeks of use. One thing you could try for a stress test is to print out a disk brake assembly and see how much force it takes to stop it or break it.

[@luke.perkin.inventor]

This is awesome! Thanks so much for bringing a vast improvement to cycloidal reducers to everyone's attention!!!

[@The_Flying_Yeti]

0:50 almost killed me! that's exactly how it feels explaining this stuff.

[@leogray1091]

I actually remember seeing something very similar, after looking around more, I think it's called RV reducer. But the one they made have a fixed housing, so the cam-disk have 6 holes on it, 3 for ecentric input, 3 for output.

[@Turalcar]

0:45 Circle, smooth and inoffensive

[@MrYrodz]

i want more resource tests like this

[@crnlbwlawson]

Great design! Would love to see it load tested to failure.

[@PhG1961]

Great work ! Maybe mount the motor and gear in a robot arm and perform heavy duty testing, like picking up some weights continuously.

[@Argosh]

Gonna be using this on the RC lawn mower I'm building with my dad! Thanks dude!

[@accordv6er]

DRILL/Impact gearbox!!!! Impacts and drills have some crazy reductions that get abused- so many good tool channels out there, a few that take them apart. Your design looks like it was made for it. The possibility of turning a larger outer "ring" for the drive instead of being limited by the shaft that has to spin inside is a HUGE deal. Especially for an impact where the rotating mass and it's moment of inertia is what results in crazy power. In the case of small drives like ratchets/electric wrenches, it could be used to move the ratchet mechanism away from the head itself. (Would still need to solve turning the drive axis 90deg) And finally -- offroad trucks/equipment especially. I'm curious how it handles changes in direction/ acceleration/load because the control involved in that reduction would be amazing. Additionally- if it can handle high input speeds, a CVT as a first stage might make for an incredible heavy equipment/semi gearbox

[@eelcohoogendoorn8044]

Awesome build. Didnt think there were any gearbox topologies I wasnt aware of yet, but seeing a new one definitely earns a subscribe. I suppose one drawback compared to a central cam is that the bearing loads are less self balancing; if you want some low backlash and low preload you need to work those cam bearings with a static radial load. Perhaps a nice way to reduce the bearing requirements would be to put the herringbone sandwiched between the offset cams (or one-tooth gears). Then if you give both sides of the ring a bit of a taper, you can preload the whole system by adjusting the clamping force on both halves of the ring; and it should also be self-energizing; you can run it at a low zero-load preload setting for efficient low torque zero backlash operation, but the radial forces should increase in lockstep with the torque demand. All without bother any bearings with those radial forces!

[@eelcohoogendoorn8044]

I guess thats another way of saying this is basically just a wolfram topology, but with a single-tooth planet gear on the output. But practically speaking its a configuration that comes together quite elegantly.

[@alttabby3633]

Best Fusion360 tutorial I've ever seen!

[@NimblyJimbly]

Such a cool video! You can tell by the way it is. 😂 Love your style and sense of humor. Your engineering skills are insane. Loved the build. Would love to see this gearbox being put to a more strenuous (perhaps more practical?) use. Maybe a ham radio antenna rotator, or a winch, or a dual axis solar tracker for a solar panel array? This is the first video I’ve seen of yours and subscribed immediately upon finishing it. Can’t wait to see more content.

[@BeanzAndBrass]

for a rather small channel you make amazing content

[@tubach1082]

I have never heard anyone else even reference neature walk before thank you for reminding me of it's existence

[@davifoss]

Your videos are great. Good camera work. Good editing and comentary. Good content. I'm enjoying it. Thanks

[@patri0t1776]

Just load it, weight the bar to like 15 - 25lbs at the wheel; and add obstacles to climb like irregular shaped fist sized rocks (or bigger if the tire won't slip) or just 3-6" or so ramps then a abrupt drop, rough terrain, etc. That should give you a better "real world" stress test. Nice video and build! Cheers, Patri0t

[@patrickcoleman6287]

Very cool. That calculus looked crazy.

[@ДмитрийБочкарёв-и2т]

you can speed up the tests by increasing the axial load, for example, by constructing a brake stand, placing the ring in a housing containing a very viscous material with adhesion to the tire surface, for example, in a rubber cover attached to the body of the test stand and creating maximum friction due to interlayer shifts, after testing, recalculating the round under normal conditions through coefficient of friction

[@aniketdevadiga1095]

Great video man!!! Excited about future improvements... Some of my personal suggestions are to make it a bit more dirt proof as there was gunk that got inside the gear box. And second would be to try to add a shifter so that you can shift it between high torque and high speed settings. While hoping it could be achieved within the same form factor

[@teagueshepard1726]

The Neature Walks reference made me so happy

[@anon_y_mousse]

Neat, and I like the semi-subtle humor. I'd love to see a follow up where you test its torque as well.

[@avoirdupois1]

One application for this kind of reduction could be archimedes screws for grain elevator type lift or water pump (using pool hose wrapped in a coil up a tilted column) if you want a system that doesn't need check valves and has intermittent power input. Would be useful for a solar powered gravity fed gray water processing system for an off grid home. Slow, but low power draw!

[@thomasmanfredotti300]

Nice job I've just printed it to build a robot lawnmower but there is a small difference on the parts called Cycloidal_Disk. The number2 external dimension is 0.2mm larger than the number 1 which is sufficient to prevent this part to roll inside the part called Wheel_rim.

[@jakubmierzejewski961]

Everything is good. Check your alignment.

[@garyrobinson3735]

Above all your efforts I only want to mention that you put the tire on backwards.. good video

[@JamiePineappleWyatt]

Add a trailing mass via a 3d printed buggy and some weights, step up the speed a smidge (preferably to a usable real world use speed), add stages for more reduction and lets find the maximum torque output before internal stress becomes visable! Great box, cant wait for the next one!

[@erik7957]

Brilliant idea, Michael, if you got it from yourself. You should know that this concept was introduced some years ago by Nabtesco (Japan) and today is the standard drive wheel reducer for Komatsu excavators.

[@newt2010]

We have RV gears in many of the drives in the robots that we sell and use. Many robot manufactures, regardless of the brand, has RV gears as well as harmonic. Just from the nature of how they are built. RV gears are much stronger than a harmonic Drive, as I have seen them fail with the flex spline giving out and actually getting torqued and twisted when they crash the robot. Very cool gear boxes.

[@johnlocke9609]

Got an idea, you can use a 24v solar panel to drive that motor using all that torque to lift (somehow) heavy stuff in to a column, to (store energy) how? when let's say 1 metric ton is at 20 feet, you can then use a rack and pinion attached to a DC motor to generate electricity when is coming down, when the temperature is really low, the voltage/current generated could be used to heat a driveway bed so your drive way is without ice in winter, all basically done by weight/ratio of parallel small dc motors stopping the weight of wherever you can get up in to the air. Some excel sheet will help to get the best numbers.

[@Totalis1989]

This is amazing, love the presentation style and design. I reckon the gear ratio for the cycloidal part (at least the one you uploaded) is 1:21, not 1:20. (Specifically, the planet gear turns 21 times for 1 rotation of the output housing. Great design, I am absolutely stealing (with credit, ofc)

[@fusionvibe]

Ohio weather been crazy this winter. mid 50's in early January. great video. subscribed.

[@TheRenaissanceBuilder]

Fantastic setup and im sure very rewarding results. Nice work

[@SaHaRaSquad]

My preferred alternative to those heat inserts are simply...M4 nuts. Print a hexagonal hole, pull the nut in using a screw, and with the right tolerances you've got a very tightly fitting, compact thread using parts you can get anywhere. For extra strength you can also get square nuts.

[@Matthew-lh3zy]

That "subscribe" printed onto the pivot *chef's kiss*

[@Twistedmetal-qe8kx]

This is awesome, great work. Looking forward to how it performs with some heavier loads.

[@trefle10]

Do you think we could drive this with a drone brushless motor instead? They spin much faster but have not much torque... so with more reduction if this works it could be cool to drive cars/tanks....

[@HappyMathDad]

Awesome gearbox. Paul gold will probably be making one tomorrow. I don't understand why these designs are not more popular. I would just mention that the planetary gears don't really get as much stress as the cyclodial gears. That's why it's a good idea to cut them like you did. I also never really liked how the pins are pushed on a typical cyclodial. CONGRATS. Btw. Everybody wants to know the efficiency.

[@michaelrechtin]

Working on a test setup that should be able to measure dynamic torque and efficiency for any gearbox. Stay tuned!

[@soyo]

nice job! Could you please cite the papers that you read?

[@AshleyWragg]

Wow awesome project! And thanks for sharing the files.

[@mikelarin8037]

Use the same setup but add some weights to it in a trailer towed behind the big wheel. Put the trailer on a wide enough base so it wont flip and a single pivot attachment point so it can move freely behind the bigboi

[@AndrewJonkers]

Put an eccentric weight offset by an arm off the hub and run it hanging off a bench - that way you get an alternating plus/minus torque on the components with the weight driving the motor on the downside of the revolution and the motor providing max torque on the upside of the rotation. The eccentric arm length and weight define the maximum torque required.

[@alexanderpalmisano3285]

Hey mate, awesome video I love the content. Just something you may have seen, that build up of snow and mud in the tyre is because that tyre tread can only go in one direction and in the video it's going backwards. All good keep it coming. 🎉

[@danon-theautisticmaker8112]

I'm re-watching this 4 the 2nd time after watching ur previous vids, & WOW what progression! I hope ur next test is connecting this design to that huge DC motor that u used in ur last for a torque test!

[@Antrim3d]

As always, great job! . ... And greetings, from Southeast Ohio. 👍

[@eulachonfish]

Elegant gearbox, and already lasting about as long as some of the irrigation pivot gearboxes I've seen.

[@FABBuildit]

You could make a sled and pull a cinder block. And scale it up from there. Might want 2 going at the same time. It would be a lot of force on the center pivot. Wait! New idea. Center pivot irrigation put the gearbox in the pivot. That would be scalable in many ways. Still the anchor would have to be sturdier than what you had. I'm sure someone else mentioned it but tractor tires are directional and you were spinning it backwards. Great video and I'm thinking about making one now on my ender 3.

[@senorjp21]

Your designs are total pro and super toit - toit like a toiger. This compact high torque design would fit well into a robot arm.

[@BadgerBishop]

This would make one heck of a RC rock crawler. Could you shrink it all down to work with the 1.9/2.2 wheels used in 1/10 scale RC cars? I mean, if you need a practical application for it.

[@Maseehullah786]

Awesome video but the tyre thread's were facing the wrong direction. V patterns thread's the arrow faces forwards . Not that it matters, Unless it's on your vehicle .

[@johnlocke9609]

hahaha! Looove the face, because is just fkn cold to go out haha! But science first so, kudos for your sacrifice! And thank you for uploading the files! Send you cyber hugs!

[@Varue]

these kinds of videos are my favorite. I love the experimentation. would love to see more. cheers

[@Caseman91291]

This is awesome! Your tires tread should be the other direction though.

[@natet.8867]

I really love this failure analysis kinda thing. Maybe you could add some load to the test set up, or maybe make a gear box without ball bearings?

[@noahagnew6517]

Interesting, is it backdrivable like a cycloidal?

[@devinholland5892]

The gearbox is a couple bucks. This video? Priceless!

[@reinierwelgemoed8171]

Awesome prohect man. One the threads inserts I believe its been proven that printing the threads is still superior to the inserts. Would be interesting if You added some weight out on the wheel in like 500g increments to see how far it would go.

[@chaselewis6534]

Imagine quite a bit of internal resistance but looks low backlash and likely has pretty high torque ratio's. Pretty cool.

[@Snagglepuss1952]

Brilliant. How about a bucket chain water lifting water feature, it would allow you to adjust the load, and look darn cool, cheers from nz

[@seabeepirate]

Pretty neat. For testing you could add a weight sled with a load cell to the boom of the testing rig. That would give you easily logged loads to create your data set.

[@thereefaholic]

3D printing seems to have improved over the last 5 years. My JGAURAIRA printer would have required me tho throw it across the room long before ever getting the first print.

[@billymonday8388]

i remember that acrylic was the big thing in DIY before those 3d printers. nice

[@joshualjohnson]

How about testing your hearing on a hydro powered sprinkler setup with a radial arm of say 150 feet where the pump supplying water to the sprinkler system is also powering your gears as it passes through. The weight of the water and the terain it would be traveling over would put load on your gears. It would need two tires for stability and they would need to be larger and move slower so gear reduction would be needed however it would give your gear setup a functional use as well as test it under load. Powering it with water wouldn’t be necessary but it would add a challenge and reuse the energy already being spent on pushing it out of the sprinkler and giving it dual purposes. Btw your tire is on backwards. the tread on a tire is meant for sipping which is pushing mud dirt etc out and away from the path of the tire rather then cupping it and pulling it towards the middle.

[@paulmcewen7384]

Pretty damn cool man. a 6x6 rc rover with these would be super cool.

[@AmbiguousAdventurer]

Your tire tread is pointing in the wrong direction. Nice video very fun to watch thanks! =D

[@prozacgod]

KZbin Engineering check list: Interesting Idea: New gear box design. CHECK! Complex Design: Multiple cycloidal layers. CHECK! Snarky Delivery: Instructions for design are the standard 3 step format. CHECK! Overlooked Mundane Detail: The tractor tires were rotating backwards. CHECK! Yep... checks all the boxes! P.S. The tractor tires were rotating backwards.....

[@maximthemagnificent]

Aluminum cycloidal discs could be made from a plastic one using a handheld router and a carbide copying bit. Might be an interesting upgrade.

[@DEtchells]

This is a great idea, not just for this project but generally: It’d be kind of like semi-manual CNC. It wouldn’t afresh small holes that need to be positioned precisely, but seems like it’d be a fantastic general,solution for profiles. I’d *really* like to see someone explore this! (Hmm, for hole placement, what If you made oversized holes that would accept metal bushings? The bushings would guide manual drilling, I wonder how accurate that would be?)

[@maximthemagnificent]

Had the idea a while ago but haven't had a use for it yet and this seemed like possibly a good application. Saw one video a couple weeks ago where someone did this to create a roller chain sprocket but can't locate it now (curious how long that part would last). I've used 3D prints for hole layouts but have so far never needed to press bushings into them for the level of accuracy (and longevity) I required. Don't see any reason the bushing method should be less accurate than the process used to produce the holes in the first place, presuming quality bits and bushings.

[@maximthemagnificent]

Managed to find that video: kzbin.info/www/bejne/ooaWlp-Jf5uDsLM

[@SportyPompano]

lol, the backwards tread. it wouldnt affect anything in this test environment, but that tread design is made to be used the other way, where the "arrows" created from the terrain are pointing in the travel direction when on top of the wheel

[@mathewblankenship7837]

Run more power to the motor and make it rotate faster. They only issues i see that would prevent this setup from lasting years would be friction and heat build up. If you could integrate a water cooling system you could potentially build a full on rover or car.

[@colbyjohnson2344]

Very cool project. I want to make one of these for my motor. Thank you for sharing this build. Nice work!

[@TheParamotorGuy]

That wheel is awesome. I would like to inform you that you are either traveling the wrong direction or the tire is backwards.

[@bender9205]

I'd love to see a rover build with this like rctestflight did. Great work!

[@davesublette7447]

If you want to test under load, make a rotator for a ham radio antenna . Start with a smaller one, then increase the size to increase wind load.

[@Falcon23K]

You know that you live in the countryside when it triggers you that the tractor wheel is going in the wrong direction. Nice video

[@anubis520]

cool video, someone told my about this. I am interested to see where you go with it in the future. Until then, I will watch some of your other videos

[@circleofowls]

Why is everyone trying to convince me to buy a laser cutter?!? Love this gearbox though, very well done and the durability shown so far is just incredible.

[@7sj3Ax]

Great video, awesome gearbox but just to clarify tire tread is supposed to rotate in opposite directions.

[@VipersHeart]

Best sound ever at 5:55

[@martin-vv9lf]

you can eliminate the planet gears in this design, by coupling the rotation of each to the next by using a con rod like steam locomotives used on the wheels. in this design, the con rod plate would have three holes arranged in an equilateral triangle, instead of the two or more in a locomotive. This would make it much cheaper to build from iron for industrial use.

[@kinzokushirogane1594]

I definitively want to see more testing, preferably much strenuous tests.

[@AdityaMehendale]

The wheel's turning in the wrong direction :) Non-sequitur for test such as yours, ofc. Nice!

[@mortcs]

What kind of backlash are you seeing with this gearbox? Could it be used to drive legs of the aforementioned dog robot? How much load can the drive handle before losing steps or breaking?

[@faraday9234]

make a roller coaster esc. circular ramp for it to go up and down on and add weight to put it under more stress. Maybe a higher rpm too?

[@customsolutionsinc]

Cool project. Even printed the tire...