Plain bearing play

[Sonic EscapeParticipant @sonicescape38234]

I disassembled the headstock of an Emcomat 7 lathe and I found a plain bearing that I think is worn out. As you can see in the video it has a significant play. I have no experience with plain bearings but to me it doesn’t look right. This is the arbor where the motor belt ends. So it can’t cause any loss of accuracy. But it will not make more noise than a tighter fit?

[jamesp1Participant @jamesp1]

Its hard to tell from the video because the shaft is moving around a lot. But it does look to have a few hundredths of a mm of movement there. It could be better but for a pulley shaft it is probably not critical. Probably not particularly noisy. But it looks like it could be a good first project when you get the lathe going, to make a bushing for itself from some leaded bronze. A nice little exercise in turning and boring with some useful outcome at the end.

[not done it yetParticipant @notdoneityet]

Question is: Was the movement on the shaft or within the housing?  If only in the housing, it could be that the bush must be tightened after the shaft is fitted and aligned, so that the housing then clamps the bush in place.

[bernard towersParticipant @bernardtowers37738]

wobbling a bush about like that does not tell you anything about the play when installed

[not done it yet]

On not done it yet Said:

Question is: Was the movement on the shaft or within the housing?  If only in the housing, it could be that the bush must be tightened after the shaft is fitted and aligned, so that the housing then clamps the bush in place.

I’m not sure that I understood what you mean by “bush must be tightened”. You are referring to a split bush?

This is what I have:

On jamesp1 Said:

But it looks like it could be a good first project when you get the lathe going, to make a bushing for itself from some leaded bronze. A nice little exercise in turning and boring with some useful outcome at the end.

Yes that is true. The bush is also easily accessible once the headstock is assembled.

[HOWARDTParticipant @howardt]

Look at the Oilte catalogue for correct mounting dimensions and press fit with the correct bore pin diameter.  Before fitting if the bush is dry soak in the recommended oil overnight.

[not done it yetParticipant @notdoneityet]

You are referring to a split bush?

No.

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