Drive Pulley has some play

You won’t wanna keep running like that with a wobble. Eventually it’s gonna wear your motor shaft from rockin.
With all the things wrong with that pulley. Bore loose, keyway to big, only one setscrew. I would just make or buy a new one and stop pulling your hair out on this. That pulley should be easily sourced and really overall size can be changed for your speed request.

You know it has no sideways play on the shaft just rotational as the key way in the pulley is a tad big so when the set screw comes loose as it does every month I pull out my hair.

But you're probably right, I probably ought to change it.
 
You know it has no sideways play on the shaft just rotational as the key way in the pulley is a tad big so when the set screw comes loose as it does every month I pull out my hair.
There's an old variant of a key, a stepped key, that fits mismatched shaft/pulley keyways. It oughtn't
be impossible to make one, That'd be quicker than buying another pulley.

Another outlying possibility: could you put a blunt-point setscrew in, and maybe a bit of brass shim at its
tip, then maybe friction on the moving key wouldn't turn the setscrew (it's a bearing, kinda). At a
prior job, we had fits on a bunch of clamping screws that got loose in shipment: same thing,
minor slippage was enough to loosen our lockwashers as the truck went over a bump.
There's occasional torque during shipping jolts, like you're seeing when the pulley key
exercises its slack keyway...
 
Stepped key is a great idea -- except I'm not seeing a matching key way in the shaft. In either of those shafts, actually. Could be a big part of the problem, it's just relying on the grub screw to limit rotation.

In the absence of a proper key way, at least put a flat on the shaft. Less opportunity for screw to wiggle back and forth.

-frank
 
Stepped key is a great idea -- except I'm not seeing a matching key way in the shaft. In either of those shafts, actually. Could be a big part of the problem, it's just relying on the grub screw to limit rotation.

Ooh, good point; I assumed it was a simple key. There could be a Woodruff key, the shaft end
wouldn't show it. Don't think there's any tradition of W-key with a step, though.
Odd image shows up that might be something like that, here: <http://a.co/903nofJ> (or
the long form, <https://www.amazon.com/OES-Genuine-Camshaft-Woodruff-Mercedes-Benz/dp/B001G7EG4C> ).
 
Agreed, could be a woodruff. Or even a stopped key way which wouldn't present from the end. However, I think either of those would be rare and unusual occurrence. Especially on something this small (as opposed to a hydraulic shaft or something).

I have cut in the occasional key way using a Dremel tool, but it's not a great way to do it and could easily make things worse.

-frank
 
I'll take a few photos today with it pulled apart so you guys can see the key, keyway in the shaft and the pulley. I might make it all that much more clearer.
 
20180526_111620.jpg

20180526_111656.jpg

Not sure this really shows much but I decided to put some brass shim between the key and the pulley keyway and its a bit tighter I hope it works.20180526_111603.jpg
 
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If the hub has enough material can you make your own version of a taper lock or QD hub?

Sorry BtoVin, I missed this, now I'm going over this thread again in case I missed something. So I'm wondering what a QD hub is.
 
Google 2 part pulley hub and that should give an idea.

It consists of a hub that slides on shaft then pulley or body slide on.

2 screws pull it on and same screws used in different holes to remove.

Simple and elegant.

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