Plain bearing lubrication

[t-chris3]

Hi,

I recently purchased a Lorch & Schmidt lathe (most probably some kind of AB Type)and when I took out the spindle for mounting a serpentine belt and checked the plain bearings I noticed that there is a axial groove in the headstock bearing in which the hole from the oiler ends.
It is obviously there for distributing the oil along the entire bearing surface but should there be a felt or wick inside to hold the oil for longer and assures a constant oil film. I have done some test runs before and I was wondering how fast the oil is going through the bearing.




Thanks for the help.

Cheers
Chris

 

[t-chris3]

Thanks, I am not sure but maybe lathes that have a groove on top should not have felt or wick because it could be dragged in between the spindle and the headstock bearing? I definitely do not want to damage it.

 

[Screwmachine]

I have numerous old small Swiss machines with no wick, just a passage and groove.

 

[t-chris3]

So the idea is that the drip feed oiler is providing the right amount of oil at a certain rate to keep the spindle lubricated at all times.

 

[jim rozen]

Same type of conical bearings on this lathe, here's a solution that provides adjustable lube to your machine:

Often these lathes had small wick feed oilers,that draw oil up over a standpipe via a pipe cleaner type wick. They have the advantage of providing filtered oil to the spindle bearing, and the disadvantage that they cannot be shut off. When you are done using the machine the oil will eventually work its way onto your bench top if the machine is not used for an length of time. Examples of wick feed oilers:

That pratt whitney lathe originally had wick feed oilers which I replaced with the adjustable, shut-off-able drip feed ones, also shown. Your machine may have had wick feed oilers originally.

 

[Joe Gwinn]

So the idea is that the drip feed oiler is providing the right amount of oil at a certain rate to keep the spindle lubricated at all times.

And clean, a classic advantage of a once-through total-loss oil lube system.

 

[t-chris3]

Thanks Jim, nice Lathe you have there! I will try to get hold of the adjustable drip feed oilers, but it is kind of a bummer here in South Africa.

 

[EPAIII]

My SB lathe has journal bearings and there is a groove in them, near the top. It also has felt oilers at the bottom which draw oil from reservoirs below the bearings. The felt rides on the spindle surface and causes no problems. The daily oiling routine includes filling those reservoirs.

As for the type of oil, strangely enough, it is called spindle oil. I purchased a gallon about 12+ years ago from McMaster. It seems to work well and a gallon lasts a long time.

A bit more on felt oilers: when I purchased the lathe the felts had been completely worn out and the springs used to hold them against the spindle were wearing grooves in that spindle bearing surface. When I discovered this, I promptly ordered and installed new felt oilers. As far as I can see, that is the only way that felt oilers can cause damage. Just to be clear, on my SB, the oil distribution channels are on the top of the journals while the holes for the felt oilers are at the bottom. The two are not connected and oil only enters those channels when dragged there by the rotating spindle.

If you install felts in oil channels that are above the spindle, there may be a danger of them wearing to the point where they no longer contact the spindle. The springs in mine take care of this problem. But, in your case, worn felts with no springs could actually keep the oil away from the spindle if the level of oil gets low. If felts weren't there originally, I would leave it that way and let gravity do it's job.

And fill those oil holes at least once a day. Actually you should hit all the oil points once a day, before the lathe is first started up. Coffee, oil can, lathe. Sip, squirt, squirt, sip, squirt, squirt, etc.

Thanks, I am not sure but maybe lathes that have a groove on top should not have felt or wick because it could be dragged in between the spindle and the headstock bearing? I definitely do not want to damage it.