Back Gear Disengaging On It's Own

If you didn't already do so (which you should have), remove the oil plug (looks like an Allen set screw) from the spindle cone pulley and squirt some SAE 20 oil into the hole to lubricate the pulley bushings. Reinstall the plug.

Then, with the back gears disengaged (normal position) but the direct drive pin pulled out, tighten the belt and start the motor. The pulley should spin quietly but the spindle should sit still. If it still makes the noise, find the source.
 
Done - the noise is definitely coming from the pulley/bull gear interface. And with the pin disengaged, and back gears disengaged, there's still enough friction to turn the spindle. If I let the spindle free wheel with the pulley the noise goes away, as there's no relative motion between pulley and bull gear. If I hold the chuck and stop the spindle rotation, the noise comes back.

What I notice, is that the left side of the bull gear seems to have some wobble, maybe just the way it was cast. It's an ebay replacement, as the teeth on the original had disintegrated. Also, I've got a lot of axial play in the countershaft with the motor running, and it's transmitting through the belt, causing the pulley to move axially, which allows contact with the bull gear. Should there be some sort of washer between the countershaft pulley (9-427) and the countershaft bracket (L3-20)? Tightening the belt does help, as it seems to constrain the axial motion.
 
My understanding is that after assembling the spindle in place in the headstock with the 10A-89 Collar up against the step in the spindle diameter, the set screw in the bull gear is loosened and the bull gear is moved on the spindle to yield 0.003" to 0.005" of clearance between the bull gear and spindle cone pulley. Then the two 10-253 collars should be adjusted if necessary to match up the two back gears with the bull gear and spindle small back gear.

On the noise problem, without watching the unit run I can't say for certain but the problem may be caused by either the bull gear or the cone pulley face not being perpendicular to the bore of one or the other parts.
 
The Oilite bushings in the step pulley may be worn so that the pulley wobbles somewhat- check that
It can get pretty bad on some machines- it was on my late 12"
-M
 
In the event that you do need to replace the bushings. it takes three. Clausing should still carry them.

Two go into the pulley. One goes into the small spindle back gear. Before separating the gear and pulley, temporarily match mark them so that you can put them back together the same way as when they came apart.

It will take another lathe to do this with but if you do pull the spindle, temporarily reinstall the Woodruff key and bull gear. Tighten the set screw. Check the runout of the side of the gear that runs against the pulley. And note that unless it should happen to come off during disassembly or you are going to change it, it is not necessary to remove the large bearing cone from the spindle. Should you decide to pull the spindle for other reasons, please report any dates found engraved onto the cups and cones.
 
Last edited:
wa5cab said:
On the noise problem, without watching the unit run I can't say for certain but the problem may be caused by either the bull gear or the cone pulley face not being perpendicular to the bore of one or the other parts.
Click to expand...
Agreed
markba633csi said:
The Oilite bushings in the step pulley may be worn so that the pulley wobbles somewhat- check that
It can get pretty bad on some machines- it was on my late 12"
-M
Click to expand...
There is a small amount of wear.
wa5cab said:
Should you decide to pull the spindle for other reasons, please report any dates found engraved onto the cups and cones.
Click to expand...
Yikes! I had the spindle out, probably a year and a half ago, but didn't record the dates. I do remember the year as being 1953.

My apologies for the late replies - I must not have email notifications turned on.

At any rate, the lathe goes to its new home tomorrow. I don't know if I related the history on this: The lathe came out of an estate in Denver. The fellow was a rail fan that passed away. The family was in Georgia and worked through a realtor and the local rail fan club to empty the house - the family didn't want any part of it. The fellow was a hoarder - the house was pretty trashed, with tools and machinery everywhere. There were three lathes, including a 13x40 Grizzly still on the pallet and two Atlas. Most of the hand tools and easy to carry stuff was already gone, as three groups of rail club members had been in there. What was left, was the stuff not easy to remove. Three of us with a pickup and trailer took out the two Atlas lathes, a Buffalo precision drill press, a ground surface plate, an 8" rotary table, a small craftsman vice, a shop press, a bandsaw, a string trimmer, various full size railroad signals, and books. There were hundreds of books and magazines from days of yore. Everything was free for the taking. The Atlas that I restored is being given to a friend - I've taken it about as far as I'm going to; I set up some tools in the 4 way post and took some cuts. It makes chips, so the rest is up to the new owner.

Thank you all for your help!

Paul
WB2EIU
 
@paul s, as hard as it is for me to believe, I never asked either you or Lastwagen for the serial number of your respective machines. Nor of the bearing dates if you had or were going to pull the spindle. It is probably too late for yours as I think that you said that you were about to give it to someone else. However, if either of you have or can get the machine serial number, please post it. Depending upon the age of the machines, the serial number may be stamped into the top of the right end of the front way with the nameplate with model number in about the middle of the rear of the bed. From around 1942 on for 10" and that or maybe later on 12", the model and serial number are both stamped onto the nameplate, and the nameplate is riveted to the right end of the bed. They all remained like that through end of production in 1981. Which is unfortunate as on the early ones, we can at least get the serial number. And at least with the 10" infer the approximate age from the serial number and other things that are visible on the machine. This is also the reason that we don't know the serial number of so many machines. About the first thing that occurs to a new owner is usually to strip the machine and repaint it. Unfortunately, if it is a later machine with the nameplate on the right end of the bed, very few nameplates with model and serial number ever get reattached for any of a bunch of reasons.

Back to the date engraved on the Timken bearing on machines so equipped, that practice ceased in early 1953. The latest date that we have on a 12" is 20 December, 1952. And on a 10", 05 February, 1953.
 
The new owner left with the lathe just a bit ago, but we're in constant contact. The SN was stamped into the right front way of the bed, five digits - I'm sure I can get that info. There was also the tag midway along the bed. The lathe had been neglected, but not used very much.
 
Paul,

OK. Let me have the S/N when you get it and User ID if he's a member or first name and last initial of new owner if not a member.
 
wa5cab said:
Paul,

OK. Let me have the S/N when you get it and User ID if he's a member or first name and last initial of new owner if not a member.
Click to expand...
SN is 30478. Not a member here, Bill D.
 
You must log in or register to reply here.
Back
Top