Certified FOCBOX Suppliers | Get Focbox Unity

Where to buy motor pulley?


#1

Hey guys! Anyone know where I can buy a 14t or 15 motor pulley? 12mm. That ships from the US.


#2

DIYes? he has them in 12mm i believe. And some 12mm belts if you know what length you need.


#3

Yeah I need 15t though. Or 14T in 12mm


#4

he has the 14t in 15mm wide - that’s what i’d get. It shouldn’t be an issue if you have 12 on 15. Shoot him a message on his site and he may have something not listed that’ll work better for you.


#5

I ordered a 14t 15mm got a 14t 12mm so…


#6

Here is where I get all of my pulleys. They are commerical grade and built very well.

Everything is precision cut and you can get them in almost any specification.

Use the menu on the left to narrow down your results.

The price is pretty good too, but shipping can be a bit much.

https://shop.sdp-si.com/catalog/?brand=sdp&cid=p346


#7

Just get them printed from shapeways in white and flexible plastic(cheapest and strongest). They have free international shipping this week. If you select extended manufacturing option during checkout it is very cheap. I have been using them for past 2 months without any problems. Once you get the pulleys, smear some CA and let it dry. That mofo will last a while.

You can get the part files here.


#8

Wait…

I thought you wanted motor pulleys…?

Don’t get printed motor pulleys… they don’t work.

I use printed wheel pulleys I made myself with one of my 3d printers, they work great, but motor pulleys simply don’t have the strength to last under the forces they are put under. Trust me, I’ve tried in every material possible. You can’t get the same tolerances that machined parts have and you usually can’t get them centered.

Also, that isn’t true (relating to the plastic options).

White plastic isn’t the cheapest, and flexible plastic is TPU, or in layman terms rubber. It will literally have zero ability to act as a motor pulley whatsoever.

Just bite the bullet and buy a machined pulley for the motor side. For the wheel side, go for 3D Printed if you want, they work splendidly.

I’ve made anything from 30T to 44T for my wheel side and all have worked great. Those files he linked are great. If you want someone to print you a wheel pulley I can do it for the cost of the shipping and filament, shape-ways is usually pretty expensive.

I would do it for like 5 bucks


#9

Dude, is that offer open to anyone? Been thinking about trying a 3D printed wheel pulley. Have you done any Kegel pulleys?


#10

It’s open to anyone as long as it isn’t more than a couple of people. Beyond that I’m probably going to refer people to either my 3DHubs or etsy store, or just start charging more.

But yea, I can and have done Kegel pulley’s before. Made one for a friend who wanted to test on his. I don’t have the file anymore, but if you have one just shoot me a PM and i’ll take a look at the file. So long as the file is sound and the designer made it correctly 3d printed pulleys are great to have. Really allows for some great experimentation when it comes to your ratio’s.

Either way, you find me something to make and I’d be happy to make it for you.

Edit- should mention @JuniorPotato93 makes designs for kegel’s. Here is a link for what looks like a very sound 36T kegel pulley with some nut chambers made for 10-32 bolts.


#11

Thanks, just looking for it. No experience with 3D printing, but I’ve downloaded the file. If you can print it, I’d be happy to compensate your time/material cost & shipping. I’m in Los Angeles area. Let me know how much and if I should email you the file.


#12

Ah my bad! I meant it for wheel pulley. Yeah the 3D printed motor pulley won’t last a week.


#13

Extrusion printing is different from the laser sintering(shapeways strong and flexible printing). I work with them all the time and abuse them and they are still to delayer and fall apart for me.

The strong and white is actually nylon. I can see you photos of my wheel pulley if you need to see proof.


#14

Yea, that makes a bit more sense. Sintering nylon is a great technique that can produce some really strong parts. It is, in my opinion, vast overkill for what we are using them for, but to each their own. Thanks for clearing that up lol


#15

No problem, just send me the file and your address to Genexprints@gmail.com


#16


Have you looked into these?


#17

Sorry, just so I learn: it’s ok to 3D print wheel pulleys, but not motor pulleys? Correct?

Edit:
Ok just read through. Got it. But why? Motor pulley not got enough material / density to withstand the stresses??


#18

Using physics it can be shown that each tooth is under 36/16(assuming thats the ratio) times more load than the tooth in wheel.
Edit1:The higher this ratio the worse it is for the motor teeth.
EDIT2: I was thinking of a gear when I wrote this. I think the analysis will be different for pulleys though.


#19

I would say it is more to do with the stresses involved with the transfer of power from the motor shaft to the pulley.
Too much force even for a key to a little plastic slot. Perhaps someone else can put this better!


#20

Here’s the easiest way to picture it.

A larger pulley (wheel pulley) has more teeth and has a greater contact area with what it is transferring power to (in our case, the wheel). Distributing the forces applied to the wheel pulley over a greater number of teeth and then onto the wheel via a very thick hub adapter that is screwed onto the wheel means it is generally going to have a much better time.

A smaller pulley (motor pulley) has far fewer teeth and a much smaller contact area to what is turning it (the motor shaft). You are asking it to transfer enormous forces for such a small piece of plastic through as little as 6 teeth. In addition to that, you are asking all of the forces being applied to the pulley by way of a small grub screw secured onto the motor shaft. No plastic is going to be able to handle the forces applied to it, nor is it going to be able to allow enough strength to tighten down a grub screw tight enough to handle those forces.

also, it is almost impossible to describe this in way of physics that makes sense because the forces are so dependent on how large a shaft you have, how many teeth and the weight of the rider.

But, in short, yes, you can easily use 3D printed wheel pulleys as long as the design is sound and you can get it centered onto your wheel.

EDIT-

OR to make it even easier, take off your current motor pulley (if you have a board) and spin up the motor and try to slow the motor down with your finger by first grabbing the motor itself (carefully of course), and then try and do the same thing by grabbing the shaft. Do this at a low RPM because otherwise you’ll end up burning your fingers.

You’ll find that it is much easier to slow down the motor by grabbing the motor itself than by grabbing the shaft. This will give you an idea of what the motor pulley is dealing with. Also, put the motor pulley back on and see how easily you can slow down the motor by grabbing the wheel, it gets even easier. This should give you an idea of how much force that little pulley is having to deal with, and how using plastic just isn’t strong enough.