Have trouble getting the spindle out

[COMachinist]

Hello Guys and Gals.
We had a break in Winter weather here in Colorado, yesterday was 57 and today 60 F so spend the last two days trying to get the spindle out of my Clausing 100/4800 lathe but when I try to remove the rear bearing, it slides up to the end of the threads and will come no futher. I can push the roller back into the race. Then slide it out over the threads then it sticks, I tapped the end of the shaft but will not slide forward. I have all the collars and pully set screws removed and the will side back and forward about 1/2” but the spindle stops when the rear bearing slides over the collar theads. I been messing with this thing for 2 days. I’m at my wits end. It has been great to be in the shop, this wearing me out.
Help please
CH

 

[kvt]

Do not have a Clausing but on mine, The threads on the end of the spindle, I hade to ensure they were cleaned up and not burrs sticking up to get things to slide over them. Once I did that got all the rear stuff removed but had a problems with the bull gear setup being stuck tot he shaft

 

[wa5cab]

It sounds to me like the effective spindle thread major diameter has grown since the lathe was built. Either from the threads that are inside of the collar pressing against them for years or from the collar set screws in the adjusting collar having the same effect. It won't hurt anything to lay a flat file down on the top of them and rotate the spindle and reduce the OD of the threads a few thousandths. Probably take two people, one to hold the file and one to rotate the spindle, as with the collar off I wouldn't want to rotate it with the motor.

 

[COMachinist]

It sounds to me like the effective spindle thread major diameter has grown since the lathe was built. Either from the threads that are inside of the collar pressing against them for years or from the collar set screws in the adjusting collar having the same effect. It won't hurt anything to lay a flat file down on the top of them and rotate the spindle and reduce the OD of the threads a few thousandths. Probably take two people, one to hold the file and one to rotate the spindle, as with the collar off I wouldn't want to rotate it with the motor.

Hum, how would the effective thread size have grown? The threads are not damaged, Nor are they stripped. The threaded collar with the set screw came off easy with out binding, I must be missing some thing that is tight on the spindle. I have a nice clear copy on the Atlas/Clausing manual exploded veiw.
Thanks any way.
CH

 

[COMachinist]

Here is theservice manual page on removing the spindle. I followed the directions here word for word.

 

[COMachinist]

Ok got it out just needed a BFG to “ gently tap it out” LOL. Now how do you tell if the bearings are bad? Funny thing is the rear bearing is marked X Temkin 14125-A and is dated by hand 3or5-30-46 and 3 for class. The Front is marked 12-3-45 no 3 for class. I guess the question is can I
reuse these bearings or should I try and get the 750.00 new 14125A-3 and cup, and the 14174A-3 and cup, if Timken has made the prodution run yet, which was supposed to been in Feb 2019. Have not been able to get that answer.
CH

 

[Latinrascalrg1]

Please excuse my ignorance but what is a BFG?
As for the bearings personally if they were working well for you i would reuse them and bank the $750 for something else!

 

[wa5cab]

CH,

Despite the file names, I would assume that the first two photos are of the rear or left-hand bearing cone and the third one is of the front or right-hand cone. There is nothing visible in the photos that would cause me to change them.

Also, there are no set screws in the spindle pulley. The one that you probably called a set screw is actually an oil plug. While you have the spindle out of the headstock, reinstall the plug snuggly but not tight. Look through the bore of the pulley and confirm that you cannot see the plug. I don't recall ever hearing of such a case on a Clausing, but the Atlas lathes also have the oil plug and every now and again, someone will come up with a machine where the PO has either tapped the hole through or forced the set screw into contact with the spindle. If they then tried to use back gears, serious damage was done to the spindle resulting in great difficulty getting the damaged area past the front bushing when removing the spindle from the headstock and serious damage to the front bushing. The pulley must be free to turn much faster than the spindle when in back gear. Hopefully that has not happened to yours. Slide the pulley back onto the spindle and check that the pulley will spin freely but without significant clearance between the spindle bushings and the spindle. If the spindle pulley bushings (bearings) are badly worn, replace them before you reinstall the spindle. Clausing either has them available for sale or can give you either the commercial part number or the dimensions (but not both has them in stock and gives you the number or dimensions).).