Spindle and Oiling

Hello all,

I am new to the site, and new to machining. Being taught by a 1941 SB9C. The lathe has been 'restored' by a previous owner, who appears to have done a decent job. It came with the usual story 'sat in a corner, rarely used, etc.' As far as I can tell, it really does seem to be in pretty good shape. At any rate, I like it a lot. I can sit down across the shop and just -look- at it. I have a few questions (probably only a few hundred more will come later).

1. The spindle seems to turn very freely in the 'forward' direction, but if I manually spin it backward, it noticeably binds. I can turn it but it is sorta tight. Could that be the (possibly new as part of the restoration) wicks binding a little bit?

2. The oiler cups on the side of the headstock don't seem to take/use much oil. I only have maybe an hour or two of run time so far, but how fast 'should' the levels drop? Is there any way to -know- the oil is getting to the spindle bearings?

3. I have read various docs (http://www.wswells.com/data/howto/H-2.pdf) showing an 'automatic oil retaining valve' in the cone pulley (3 speed). When looking down into the hole under the screw, I can see something down in there, but I can't feel any movement when pushing on it with a narrow punch. Do they all have a valve? So I guess the question is again, how do I ensure I am getting oil in there?

Thanks for any help anybody can share on this.

R. G. Sheehan

The spindle oil system is one of the few non flow-thru lubrication systems on the lathe. In other words, it reuses the oil, so you won't see it drop much. You'll know it is not getting oil when it starts getting really hot. It should turn the same in both directions. Quite possibly you have some debris in one of your bearings.

The oil valve probably isn't on your lathe. It replaces the screw. You remove the screw and put in the proper oil, then replace the screw. It is a necessary step when you are using the back gears.

rgsheehan said:

Hello all,

I am new to the site, and new to machining. Being taught by a 1941 SB9C. The lathe has been 'restored' by a previous owner, who appears to have done a decent job. It came with the usual story 'sat in a corner, rarely used, etc.' As far as I can tell, it really does seem to be in pretty good shape. At any rate, I like it a lot. I can sit down across the shop and just -look- at it. I have a few questions (probably only a few hundred more will come later).

1. The spindle seems to turn very freely in the 'forward' direction, but if I manually spin it backward, it noticeably binds. I can turn it but it is sorta tight. Could that be the (possibly new as part of the restoration) wicks binding a little bit?

2. The oiler cups on the side of the headstock don't seem to take/use much oil. I only have maybe an hour or two of run time so far, but how fast 'should' the levels drop? Is there any way to -know- the oil is getting to the spindle bearings?

3. I have read various docs (http://www.wswells.com/data/howto/H-2.pdf) showing an 'automatic oil retaining valve' in the cone pulley (3 speed). When looking down into the hole under the screw, I can see something down in there, but I can't feel any movement when pushing on it with a narrow punch. Do they all have a valve? So I guess the question is again, how do I ensure I am getting oil in there?

Thanks for any help anybody can share on this.

R. G. Sheehan

Click to expand...

RG---My spindle (SB9, B model) turns just as you described. I wouldn't call it a "bind", but there is a noticeable "resistance" (not a lot, but it's THERE) when manually turning the spindle in reverse, as opposed to the normal direction of rotation. I also wondered about this, so glad (I think...) to know that mine is not the only one that has this characteristic. It has been that way since I acquired the lathe some 30+ years ago (2nd owner), and have used it quite a bit over the years. So, not too worried about it, but yes, I did wonder about it in terms of whether this was "normal" or not. I'd say just keep her well oiled and RUN IT

<<Reuses the oil>> Okay, now the tech note I saw somewhere about using a 'sucker' to pull out some of the old stuff and replace it makes sense.

<<debris in one of your bearings>> Yikes. That doesn't sound too good. I have not run it enough for anything to get hot, but I'll keep an eye on that for sure.

I was asking about the oil hole in the cone pulley on the spindle, which I would think needs lube whether in back gear or not. Oiling via the screw on the back gear shaft seems pretty straightforward.

(Oops, light bulb finally comes on. That cone pulley lube is for when the pulley is running at a different speed than the spindle, when in back gear. Got it.).

Thanks a lot for your response.
R. G. Sheehan

QC,
Good to hear there is another one with a similar characteristic that still has worked well for a long time. I guess we'll see how it goes.

rgsheehan said:

QC,
Good to hear there is another one with a similar characteristic that still has worked well for a long time. I guess we'll see how it goes.

Click to expand...

You probably don't have a "feel" for your lathe right now, so what you are saying by "binding" may be a normal thing. The wicks should put the same amount of pressure on the spindle in either direction. Make sure that your reversing gear isn't binding. Retest your spindle with no load on it (disengage all gearing). There was a thread not too long ago that had differences between forward and reverse turning that turned out to be a piece of debris situated just right to bind in the reverse direction.

Removing a 9" spindle isn't all that difficult and is a fairly quick procedure. I'm not saying that you have to do it, but just know that it is an option, but eliminate all other possibilities first.

Also: remove belt before analyzing spindle drag. Most sb spindles are total loss - meaning they need to have oil cups topped up after anywhere use, between
every hour of actual spindle run time, to every ten hours. Give or take.

Definitely disengage the gear train from the spindle. Gear teeth after many years tend to wear in one direction. When reversed, causing slight binding until the friction is broken, if it ever does.

If you insist on removing the spindle, pay close attention to the spindle key under the bull gear. Make sure it is on top dead center when pressing the spindle out. Failure to do so can possibly damage the cast iron bearing surfaces of the head stock housing. Ken

If you continue to have the same situation with spindle "drag," try this: Suck out the existing oil from the oil reservoirs. Re-fill with a synthetic 0W-20 automotive oil. Yes, there will be cries of "foul" from the strictly South Bend Oil crowd but this is an experiment and not a life-long recipe. I found this to be a "fix" for the same situation on my 1936 9" workshop lathe which has top oilers with its gravity fed, "drooler" oil system.

It is also possible that the felt wicks have had their fibers beveled off in one direction from from long hours of running forward. Theoretically the felts should exert the same pressure on the spindle regardless of direction of rotation but the little fibers in there may take a set or be beveled off from running in one direction.

So long as the bearings don't get very warm I wouldn't worry about it a great deal.