Motor pulley slip

Tested the board today and after 5min the motor pulley slipped. How should i attach the pulley to the shaft? Just Loctite? I have seen talks about keyways. What are they and do i need one? Using maytech 6355’s


if you have a key way cut out in your pulley then it seats better and theres no slipping around the shaft although could slide laterally… I dont have a keyway on my pulley so i just tighten the screws into the key way groove… nice n tight…yes on blue loctite and be patient and wait the 24hrs for a full cure…

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Did you not use loctite for your set screws?

In order of preference, from best to worst in my opinion:

key in keyway with a setscrew (best)

key in keyway without a setscrew (almost as good, some mild retaining compound may be needed to prevent lateral movement)

setscrews on flat(s) (pretty solid)

setscrews in keyway (this is usually pretty solid but may damage your keyway and make it difficult to remove later)

setscrew in a drilled divot (works, but not a lot of holding power if only one)

Loctite retaining compound only (depending on the compound, surface preparation, fit, plus a million other factors, either this will be a forever joint that will only come off with a bearing puller and vigorous heating, or it’ll fail at the least opportune time. Do not recommend.)

setscrew on plain round shaft (This will inevitably cause trouble - if the shaft is harder than the setscrew it’ll just slip and not hold, and if the setscrew is harder than the shaft it’ll raise a burr and you’ll never get the pulley off again.)

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It was just a test run before locking everything…

This is what I have. My motors shafts do not have a keyway nor does my pulley. My pulley has 2 setscrews. Should I just use loctite blue 243 (or another?) on the setscrews or should I fill the divot with something?


Without loctite the pulley will slip, even durning bench test due to vibrations

Put some loctite in the grub screws and tighten screws and wait at least 24 hours for it to cure.


The motor shaft in the picture of your first post does have a keyway.

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243 on the setscrews should be fine. One cheap and easy upgrade that will save you headache later: replace the Chinese setscrews made of cheese that come with most drive kits, with proper class 12.9 ones. It’s a $2, 5-minute job that will save you time and headache later.

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