3D Printer Gearbox - Spinning it FAST

Put some silicone lube on the gears/shaft, or hook em to ball bearings. That'll really knock out some of the friction :)

Truly an engineer moment when the placement of things doesn’t cross your mind until you have to take what you built apart

You need a flywheel on the highest Gear so it stops constantly losing momentum every time you stop cranking

Use a square rod with a keyway through the gears as opposed to cylindrical. Then you can drive it with a high torque drill. Lubricate the gears. Put a propeller on the end, brace for takeoff

Very cool. Maybe you should key the handle.
Use a file to put a flat section on the axel and then have that slide through the plastic handle, with a lock pin either side.

I wish you’d put a contrast color line on each one so that the speed of rotation shows up better on camera.

“There should be no problem with the box coming off the table”
*Table comes off floor*

The way you made the screw near impossible to reach kind of makes you a real engineer

Still waiting for the yet unscheduled disassembly event to finally get scheduled! Gonna need a stronger connection from the lever to the first gear though, crazy amounts of torque need to get delivered!

Alternate title: "how to build a really good pencil sharpener"

This is weirdly cool and satisfying and educational.
Dunno if you could use a laser rpm counter. It'll be cool to actually see the measurement

The spokes in those last gears might make them lighter, but it's also going to add drag. A solid gear with less infill will the job done better.. It'll probably help keep the fastest gears better in-circle as well. The last several gears would benefit in being balanced. The vibration and wobbling adds a ton of drag and is causing most of the plateau you are hitting. Reducing tolerances between the gears and shaft would help with that as well (+1 on the idea for quality ceramic ball bearings). With those tiny changes, I bet you could go a lot faster, and probably with much less force.

If you have the appropriate tools, try bending part of the metal shaft to make it into a handle itself rather than depending on some sort of glue to hold a handle in place

Lube all the contacts + use router bit bearings between the shaft and the gears, these are made for high speeds, and you'll be able to get faster with the same input force :)

You should start putting a black mark along the gear at even intrevals, either a single line, (center to the outside), or a pie slice colored in, to allow the casual viewer an easier time counting rotations.

I would like to see an output side flywheel of some sort. Even adding weights to the final gear. It would make it harder to start but i think increasing the momentum would help maintain speed.

I might try using a hex shaft with hex bearings. The hex makes it so you don't need to epoxy it and the bearings will drastically decrease friction.

Fantastic!! I'm planning to be a mechanical engineer, your videos are very inspiring!

Infrared camera view of that construction would be fun. Would be interesting to see where the Energy gets lost.

loved the no waste method of using the old handle inside the new one

Since you are testing extremes, you could remove all internal right angles and replace them with rounded transitions.

If you do it again, you can get a 12” 1/4 or 3/8 ratchet extension and use a long ratchet to turn it, you can crank it back and forth to make it easier. That way your drive (minus the gears) will be all metal including the handle :)

You should try using press fit bearings if possible. You could use an oil, or a specialty low friction grease like "slick-oleum" as a lubricant in the bearings. I have a feeling that the biggest obstacle to higher speeds is the friction in the system.

For the handle, grind a flat side on the end of the metal shaft and match that in the handle. Then you get mechanical structure to reinforce the JBWeld.

You should add keyways to the gears and use a keyed shaft

Also you may want to switch the gears being even number of teeth to a gear with a prime number of teeth. It tends to work better.

I wanna see a sequential styled gearbox should be pretty fun and interesting to see.

Would be cool for you to get a digital tachometer, to compare the calculated gear speed vs actual. If the prints are good the calculations are probably accurate, but would still be a great video aid to see the numbers digitally!!

Use a steel handle. Apply a notch in both the handle and axle. You can use a steel block to lock it. This is very common on lawnmower output shafts when mounting a blade

It would be great if some small ball bearings are used for the gears to reduce friction on the shaft , quite possible it would help spin the gears even fast due to less friction .

Last gear was spinning 167 times in a second, that's wow!

Have you tried a version with a flywheel on it? Maybe it might help store some of that energy to keep the lightest gear stable.

I found this very interesting.
Keep up the good work.

Sometimes I’m surprised these things don’t catch fire with how fast they spin

if you’re having problems with the handle mounting to the shaft, i would suggest recreating something like a vice handle by drilling a hole through the shaft itself and putting something through it 👍🏾

One idea is to attach an engine to the arm to make it spin real fast. And add a propellor on the final gear to make a jet engine :D

I'd love to see a gear system like this used with a Fan. Just to see how well it could shift air or cool a room.

Great video!! To more securely attach the handle, scuff up the shaft attaching point with a grinder or file, and use acetone or alcohol to clean any oils off the steel. That will make for a much stronger bond with the epoxy. And as others have suggested, use some silicone grease on the gears on the shaft, and teeth. Do the grease part after the epoxy part, or you'll have a lot of trouble getting the shaft clean enough for the epoxy... Expect most of it to spin off, especially the faster gears. Smart on varying the infill and thickness from slow to fast.

Finally, a video where a gear with ridiculous ratio is turned the interesting way!

Cool project!
I noticed you use hot glue a bunch... Have you played with UV resin yet? I started using that stuff instead of hot glue and absolutely love the stuff.
It's a bit runnyer so it won't work in ALL glue gun instances but I find it cures just as fast and holds much nicer in many cases

You should have added a flywheel on the last gear. That way it wouldn't stop spinning so quickly after you stop inputting energy

Cold weld is an excellent product.
Perhaps if there was a slot in the axle to allow the JB to key onto the shaft, you could mitigate the failure you are seeing?

06:01 What we like to see next? Faster spinning Gears of course!

Some ideas from an engineering dropout, rather than substantially thinner gears on the faster end, decrease the infill on the print, you're losing efficiency from the thin plastic flexing as it spins fast. Some combination via trial and error may be needed.
You're never going to get adhesive bond to an axle to hold the kind of mechanical advantage you're working with on the handle, it's surprisingly easy to key a shaft with a dremel and then use a dab of jb weld to secure the key. Lastly, bearings might seem like cheating but you should definitely have something there. Might I suggest brass bushings and a bit of lubrication? They can work a dream and aren't too difficult to make.

I figured out that if you print with bridging under the gear you can get the sharp tooth gear to print with perfect print. Just raise the model slightly off the bed and use auto bridging.

Pessoas como você, tornam a minha vida mais fácil.
Obrigado.

I wonder what it could use that much rotational force for,. I would like to see you incorporate a flywheel into something like this one with maybe a clutch I think it would be interesting. 👈 Getting smarter never hurt anyone, well atleast to my knowledge 👍

Watching the handle crank the last gear is extremely satisfying for some reason

this man just sacrificed a perfectly good table for a youtube video, props to him

Id like to see a small motor attached at the end gear. Use it as a generator. That way you can measure the voltage to which it produces. You can calculate the speed with that.

Tip, put a slot into the metal, then sand the end and jb weld it like that, the weld will fill the slot and adhere to the smooth metal better

I am sure the suggestion is here, but I would flatten the sides of the main shaft where the handle connects so you can get so more torque.
Second you can get a laser tachometer for under $30 to give you a pretty accurate read.

How about using a rod with a bent end which would be your lever and handle? That way, the lever getting loose or breaking wouldn't be a problem. You can just focus on making the gears faster and faster

Imagine this made out of tungsten with a impact gun at the end of it. And the.. really curious how fast it would go

I wonder where this series is going?
Don't end this until you reach a million RPM!

This video was super well made and you have a great personality. Keep it up!

For your handle you can make a cut in the shaft to have something other than a round section to grab on

Some advice (I use printed gears in a lot of prototypes). Cut a slot into the shaft with a dremel, much like a flat head screw or throttle body butterfly. Have a slot in the gear that is 2x shaft diameter in depth. place a flat piece of metal in to lock them in place. Functions the same as a woodruff key, but much more suitable to 3d printing.
Also, Taulman bridge nylon isnt much more cost than abs or pla, but is MUCH more slippery. Often requiring little to no lubricant on meshing surfaces.
Also, where you put the shafts through the mount, split the model horizontally in the middle of the holes along the layer line. Then bolt the top half of the shaft mount on.

Mechanically pin the handle to the drive shaft a small steel pin along with the job weld will get you going pretty good

Try sanding or making a few keyway on the handle so it can't slip out of the JB weld.

I would love to see you try this again with the gearbox semi submerged in a low viscosity fluid to help reduce friction.

If you would just hold the handle right you could crank it slowly increasing the speed and you could get it a lot faster im sure. It’d reduce the pressure on the handle it has when you just put full force onto it from a stop.

Make the handle part so you can place a drill on it, put drill on low torc and rev it, then put a generator on the end and you will have made more power than the drill uses (I wish, but it will go fast tho), also when you have it up in speed, it should take less force to keep it turning, ergo you can go from low torc to fast when it is going for full, maybe ;)

Do you think a flywheel on the output could help it spin faster?

You should see if someone can't forge you an iron rod with a built in handle so it can't break, see how far you could push it

I need to see what happens if the largest gear spins as fast as the smallest gear

I'd love to see you drive a flywheel with two (or one, two might be too crazy) different gearboxes and try "dumping the clutch" into one that's difficult to drive! It'd be really cool to see the law of conservation of momentum at work :)

JB weld is great. I use it in rocketry for filleting the fins. It does not melt like most other epoxy does, 10/10

Dumping powdered graphite on all contact surfaces on the gears and shafts would definitely help with ease of movement.

You should use lubrication
Mostly to reduce generated heat.
Also scale down the last gear a lot so you have even less spinning mass.
On top, maybe try belted gearing. It's more efficient!
And use bearings for the gears

You could at least sand the part you glued. Making it a square shape or putting in slots would be better. A hole with another rod going through it for extra support would be even better. But that’s going way outside your printing thing which is the whole deal. Really cool.

It would have been amazing if the part of the handle that you grab onto could rotate inside of the crank so you dont have to rotate your hand as you turn it. also a bigger handle so you could get a really good grip on it .

Obviously bearings and lubricant would help, I also had the idea to go up by each gear but you covered that here. I think each gear should be solid on the outside like youve done previously. My only other fun idea would be put golf ball pips on the sides of the gears

Imagine how fast you could go if you have this in your bike and you would have the strength to use it.

When I was a child, I my dream was to build a plane using a mechanism like this, and power it with my legs. My legs were extremlely strong when I was a child

You should make a metal handle or use a longer bar for the shaft and bend it (check some old hand drills for the shape), and use the same shaft to spin it.

You can't just depend on the chemical bond of the JB weld. You need an physical bond like an pin or an joint, even making scratches on the surface of the material that needs to be glued will allow it the glue to have more grip on the material so you won't have the jb weld failing.

Thanks for the video :) Perhaps wear some eye protection, a face shield, and some additional protection such as a wall in case a gear spins apart or something else happens.

Replace the lever with a circle, and maybe tie a string around it with a weight at the ene to keep it spinning

You may want to add a small amount of lubricant to the gears. That should quiet the gears as well as reduce the amount of friction in the system

You should serrate the Steel dowel and then put the jb weld on it. It will grab better than a smooth steel surface

I always wondered, if you could use something like this to charge up devices. And if you could. How many gears would you need to make it charger faster then just plugging your phone, or power brick to the wall?

Could you attach something to the fastest gear, or make a small bit of it a different colour so we can have a better visual queue of how fast it's going?

Maybe it would be easier to rotate if you have made the fastest last gear heavier. Inertia will help you after few seconds.🙃 also you will get mechanical battery with heavier last gear.

Try using a Dremel tool on the "Driveshaft" to allow for the Jb weld to attach better by scuffing the surface

Would be awesome if you put like a propeller on the smallest one so we can see the true velocity it gets

Epoxying the gears to the shaft, after screwing the mount to the centre of the table is a great example of an engineer saying “well it works on paper”

I built something similar out of K'Nex as a kid. It was impossible to turn the first gear without breaking the plastic pieces, or just having the thing fall apart under the torque.

Trust me this idea is flawless. First you make a 9/1 rope system so it’s really strong. But the trade of is its slow. So you make a 1/9 and attach it to the 9/1. Genius

Have you considered applying a gearbox like this to something like a bicycle and using it to ramp up an alternator? I’d be curious to know if it increases power output or if it would make turning it impossible from the load on the final ratio

adding some bearings or at least lubrication to the faster gears to reduce friction may help you get more speed.
insane to watch 3d printed parts spin faster than an engine. great work!

Use an RPM meter next time, and run the input with a super strong stepper motor!

If you make the handle longer you'll be able to turn the gear easier with leverage

Had to give a like for the elegant piano playing while you vigorously attempt to pull out the last screw

Try a giant turn handle you can only spin outside or something. It would be hard to get the thing upright but once you get it you can put your body weight into it. Nvm heat would be an issue.

make a gear box that ratios up and then back down so that the starting gear moves just as fast as the last gear, while the gears in the middle spin the fastest.

Nothing like honest clickbait delivering on the common request of "Please just spin it as fast as you can, even if it breaks, that's the point!"
You truly are a gift to this particular Clip-Share niche.

To make you life easier and increase the possibility to spin faster you should ad flywheel to your gear, otherwise every time you stop to rotate the handle you lose the momentum

You should made a crank powered fan for summer time.
Something that can go fast but doesn't need energy enough to make to sweat.

Next time if you don't want to break the JB weld off of the steel rod put some lines into the steel rod so that the JB weld has something to sit into