Motor v-belt pulley issue/question

I heard a strange rattling/rumbling noise inside my 219os. Opened it up and added oil to the motor thinking that may just be it but it didn’t help. Then with the base open noticed that the pulley was bumping around. I took it off and the motor spins fine. I’d never had reason to remove any of those parts and was totally unfamiliar with how the motor actually spun the ink drum. I’ve had discussions with Fritz and Dave Seat about some potential issues with the chain and idler actually running the drum, but this issue is at the source.

From what I can tell/understand, the way my motor is rigged, it has a shaft that has a flat edge on it which rotates. Attached to this is a pulley with a bushing in the middle. There is a hex set screw which runs through the pulley and the bushing and I’m assuming against the motor’s shaft. It seemed loose. Maybe the set screw had worn down, or worked itself out.

When I took the pulley off, the motor spun perfectly. When I reattached the pulley and tightened the set-screw, it spins smoothly and the pulley stayed tight. But when I put the v-belt back on the pulley then put it back on the motor and tightened the set-screw, it started rumbling again and seems to somehow work loose.

Am I not tightening the set-screw enough? Is it a question of the alignment on the shaft of the pulley with the gear the v-belt is attached to? Could the bushing wear out? Is this a normal way for these presses to be set up? Any thoughts on what could be wrong, and how to right it? I don’t think any of these are original parts, but something put together when the press was refurbished. There seems to be a lack of information about how the 219os was originally set up.

 

I’m attaching some pictures. The first picture is the motor and the bare shaft. You can see where the set-screw was pressed against the shaft. I didn’t notice if there was much of a mark when I took it off, or if this is brand new from me tightening the set screw and having the shaft fight it.
The second photo is of the pulley, you can see the set screw on top, and the bushing that was inside the pulley is setting next to it.

The third photo is the pulley with the bushing in it, you can see the set screw sticking out and at the bottom, the allen wrench.

The last photo is not very sharp but is the set screw.

Any thought/suggestions/advice/etc is, as always, much appreciated.

 

 

 

 

Motor v-belt pulley issue/question

7 thoughts on “Motor v-belt pulley issue/question

  • August 26, 2012 at 1:05 pm
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    i put the pulley back on but a bit further out on the shaft and with more pressure on the set screw and it seems to be holding. Now I’m still just hearing a lot of noise from the chain, and realize going back to some initial issues that it’s a tiny bit long. I moved the idler to the top of the chain and it worked but the chain was still slapping against itself.

  • August 26, 2012 at 11:26 am
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    I filed the shaft a bit and bought a new set screw, but when I put the pulley back on with the belt, it still works itself off.

    I don’t understand how when I put the pulley back on without the belt and tighten it, it spins fine and stays tight, but when I put the belt back on, soon as I start the motor up, the set screw loosens until the shaft isn’t driving the pulley any more.

    In the long run, I’d like to eventually make sure I have a motor running the correct speed, with a keyway on the shaft matching the correctly sized pulley. Before I get that far, I may try to replace the pulley with one with the correct sized bore so I can at least remove the bushing from the equation. But as usual I have some printing to do and was hoping a quick fix would hold up for a little bit at least. I really don’t get why using the same set-up as before, the set screw through the bushing against the flat part of the shaft, I can’t get it working. Any thoughts?

  • August 24, 2012 at 12:52 pm
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    The way my press is set up is the shaft has a pulley with bushing on it driving a v-belt that connects to a much larger and older pulley which looks old. This pulley is on a shaft that drives a chain which turns the ink drum. Pretty similar to the schematic fritz posted, except for the idler potentially being in the wrong place.

  • August 24, 2012 at 10:25 am
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    I’ve seen several old style 219s, and all had direct drive by flat belt and single pulley, no reducer.
    [Retraction: I was just going from memory, and now realize that I am projecting the situation of one particular press onto the others seen. That press did not have original motor and fittings, and was a fairly slow rpm motor. And even so, since the drum remains chain driven, there is some sort of trasition from belt to chain, and maybe it is a reducer. I can also picture one press with an original motor that had a large diameter v-belt pulley.]

  • August 24, 2012 at 9:46 am
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    We had two of the later model 219 presses which were scrapped several years ago for lack of a buyer. I wish we had them for sale today!

    Anyway, I did keep some parts, and have the gear reducer unit which reduces the higher speed motor to the correct speed for running the ink drum. If that unit would be of any use to you, we should talk. I don’t know if the earlier models came thus equipped, or just depended on the belt pulley sizes to correct the speed.

    John Henry
    cedarcreekpress@mchsi.com

  • August 23, 2012 at 8:19 pm
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    Thanks. I’m sure it’s not original. It may also be too fast. Dave Seat said as much and I think you noticed it on a video I posted for you. I didn’t know if the issue was the motor or something to do with a pulley being the wrong size, but now I’m thinking it’s the motor. Regardless, the other thing that’s different is the idler is inside the belt whereas in the schematic you posted, it’s above. This may be a good time to take care of all these problems, but initially I need to get it working again.

    The motor shaft does not have a keyway, so is my best option to get a new pulley, with a bore the correct size for the shaft, and use a set screw on that? Then I wouldn’t need a bushing. Why is a split sleeve bushing preferred? I’m not familiar with why a bushing would have a split sleeve or not.

  • August 23, 2012 at 6:18 pm
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    This is most likely not the original motor. The sleeve appears to be a solid type and the set screw has to fit in the hole on the sleeve to reach the motor shaft. Ideally, the motor shaft should be sized to the pulley shaft, and then the keyway in the pulley would match a corresponding keyway on the motor shaft and a key keeps the notor shaft and pulley together and the set screw keeps the pulley from working off the motor shaft. The better way to do this is to use a split sleeve bushing that allows the set screw to reach the motor shaft without having to align a hole in the bushing, but this kind of set up is doomed to contant retightening as all that keeps the pulley going is the set screw and it is under too much stress.

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