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dsc
20-02-2014, 09:40 AM
I got a bigger Nema 34 motor recently and ordered a pulley from BeltingOnline to match the shaft on the motor. Tried it out yesterday and the keyway on the motor shaft seems to be cut at an angle, see photo below. This in turn causes the pulley to get stuck as the key sits at an angle. Pulley fits fine on the shaft with no key, also the key fits nicely in the pulley keyway. Put all things together and it's stuck.

Any ideas on how to fix this with no heavy machinery?

Regards,
T.

11655

Clive S
20-02-2014, 10:17 AM
I got a bigger Nema 34 motor recently and ordered a pulley from BeltingOnline to match the shaft on the motor. Tried it out yesterday and the keyway on the motor shaft seems to be cut at an angle, see photo below. This in turn causes the pulley to get stuck as the key sits at an angle. Pulley fits fine on the shaft with no key, also the key fits nicely in the pulley keyway. Put all things together and it's stuck.

Any ideas on how to fix this with no heavy machinery?

Regards,
T.

11655How about a simple file either file the keyway or the key ..Clive

magicniner
20-02-2014, 11:25 AM
How about a simple file either file the keyway or the key ..Clive

+1 For this solution, there's no substitute for good benchwork ;-)

dsc
21-02-2014, 10:08 AM
I'll swap the motor and hopefully get a properly cut one. The misalignment is pretty severe, so filing it down would be a long process, especially with the keyway being awkward to work on and the material being hardened steel (or whatever the shaft is made of).

Regards,
dsc.

Swarfing
21-02-2014, 01:11 PM
I would say that the key way on the pulley is out of line and not the motor, just get a file to it.

magicniner
22-02-2014, 10:04 AM
I'll swap the motor and hopefully get a properly cut one. The misalignment is pretty severe, so filing it down would be a long process, especially with the keyway being awkward to work on and the material being hardened steel (or whatever the shaft is made of).

Regards,
dsc.

Motor shafts turn & mill fairly freely, I had to reduce a 3/4 Hp 3 Phase motor shaft size to keep my mill internals standard when upgrading it, I think you'll find a file or even Dremel with a bur will do the job nicely, the pulley should file easily and as Swarfing said appears to be the location of the problem,
Regards,
Nick

dsc
22-02-2014, 11:56 AM
The motor went back now anyway, apparently the replacement is much better, I should get it next week.

As for the misalignment, here's the photo with some lines added, you can see that the centre line for the shaft is off.

11684

Regards,
Tom

EddyCurrent
22-02-2014, 12:00 PM
If you import the image into Sketchup as a texture then draw some lines extending from the keyway sides, it appears both shaft and pulley are out.

Edit: Tom, you must have had the same idea at the same time :peaceful:

dsc
22-02-2014, 05:27 PM
Edit: Tom, you must have had the same idea at the same time :peaceful:

Lol, indeed :) although my mark up was with MS Paint!

Regards,
T.

dsc
25-02-2014, 02:25 PM
Just a quick update to praise Gary / Steve (Zapp), not only did they collect the motor for inspection, they also went through the trouble of making sure the pulley fits properly (re-broached it) before sending the whole lot back. Proper customer service and beyond.

If you are reading this, cheers guys.

Regards,
T.