Mounting 3D printed pulleys to the motor drive shaft?

Hi there, I am having problems with mounting a 3d printed HTD5m 15mm width pulley to my sk3 5055 motor shaft. Currently, I have a set screw going through the printed teeth into the drive shaft, which I have dremeled flat. I know 3D printing isn’t ideal for the motor pulley, but I don’t have the money to but them right now. I am printing with Nylon, as it’s the strongest I have. The problem I am running in to is after about 10 feet, the pulley starts slipping on the drive shaft. I used to have the problem of the pulley falling off the shaft, but I seem to have fixed that.

Anyone have any ideas? How did you solve this problem?

I wound’t recomend 3D printing for the motor pulleys, since there are fewer teeth’s in mesh the stress in much greater than the wheel pulley

I tried it one time, it lasted approximately 100m before half of the teeth were destroyed

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This^ 10chars

Even with nylon? Isn’t this kind of thing what nylon is made for? Like I said, it’s only temporary for about a week or two. Currently it’s at 16 teeth, but I can adjust it to around 20 so there’s more contact.

screwing them down didnt work for me. i filed my motorsdhaft into a D shape and just glued it on. which worked for last ~100km so far.

I’ve tried glueing it using JBWeld, but it came off as soon as I tried it. It might be a matter of needing to file it down more so it can have a rougher surface to grab on to. What kind of glue did you use, what motor do you have, how many teeth on the motor pulley, and what material did you use to print?

Turnergy 6374 190kv, 15 or 16 teeth and loctite 648. but to be fair, the glue had about 2 weeks to settle and also, im not realy sure if i just got lucky since the glue is actualy metal glue and should not realy work to well with nylon

Good to know. Is there any way I could see the original CAD file, or at least the STL? Thanks for your help!

this is what i used. you can just generate about every gear u need with this (using scad)

here is my edited version with the added D shape https://www.thingiverse.com/thing:2794331

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Have you had to replace your 3d printed pulleys at all? If so, what happened?

the large one (wheel) including the motor pulley, 1 time . it failed because the smaller one failed (petg) and that one failed because i had belt skipping before. so i completly overtightend which led to way to much friction resulting into heat which just melted both pulleys. lesson learned, sticked with skipping belts while braking and so far the parge one survived.

the small one i replaced (while experimenting) a few times.

  • no 1, PETG, failed because i didnt use enough wall thickness (2 layers). broke at the screw holder
  • no2, PETG, failed because i overtightend the screw which cracked the pulley allready
  • no 3, PETG, worked flawlessly, but i had to remove it because i got a new mount
  • no 4. PETG, wasnt put on properly (had a slight angle) and wobbled. because my new PETG i had back then overextruded liek alot and i couldnt fit it on propberly and had to use some brute force.
  • no 5, nylon, failed because the d-shape on my motor shaft had to sharp edges which basicly cut through the nylon when accelerating hard. could have also been not enough infill. no screw this time
  • no 6., nylon, was glued on, no screws and i removed the shard edges. infill was grid at 50%. so far, so good ^^

i use all 3d printed parts; PLA, HTCFPLA, PETG, ABS, TPE.

never used metal parts yet…on the way though so i have comparison.

biggest thing that helped me out attatching motor pulley was this… https://www.amazon.com/flite-Prop-Adapter-8mm-Shaft/dp/B001J8R8ES

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also added guide walls to both motor and wheel pulleys to prevent belt slipping off

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How this helped you out? Don’t get it?

Say again??

Can you post a picture of your setup so I can see what you mean?

I currently have nylon on hand, so I will continue testing. I made my own pulley with the D thing, so I will see how it works. I have been doing between 6-8 walls on my prints with 40% grid infill, and haven’t had any problems with it breaking, I just can’t get the grub screw to bite into the nylon enough :laughing: I will keep the sharp edges thing in mind. Is there any other suggestions you might have? Sorry about all the questions, I just want to make sure I get it right this time! Thanks!

What material and settings in terms of wall thickness and infill did you use for the motor pulley? What motor did you use? Out of curiosity, what did you use for a motor mount? Mine is 3d printed with steel rods through it, prototyping with PLA and finished product with Nylon and eventually carbon fiber filled.

i know on 3D printed rod couplings for nema steppers, some make use of a Nut that slides into a void on coupling similar to this…

although i would recommend doing 2… as to balance it out.

my linked pulley has this, but those are pretty unreliable with the amount of torque the motors spits out. its to punctual