Craftsman 101.28990 12" Metal Lathe - Refurb

[mickri]

If belts are not loose, loosen the belts so everything can spin without trying to spin the motor. If the back gear is not engaged will the bull gear spin? And will the spindle spin? They should spin independent of each other since the lock pin is in the out position. When you engage the back gear and with the belts loose you should be able to easily spin the spindle and the bull gear should spin at a much reduced rate compared to the spindle. If you can't spin the spindle with the back gears engaged then the back gears are probably frozen on their shaft. I just checked this on my lathe. With the belt loose and the back gear engaged I could easily spin the spindle and the bull gear spun at a reduced rate.

 

[rhjo51]

Thanks I’ll try this in the morning. I appreciate your help. - Jim

 

[wa5cab]

Well, there is an easy way to answer the question of whether or or not the back gear bushings are stuck to the back gear shaft. First remove the oil plug from the 2-groove spindle pulley. Squirt a good bit of oil into the hole and then reinstall the plug. With the back gears disengaged, start and run the motor for a few seconds. Stop the motor, engage the back gears and re-start the motor.

The set screw that bears on the Woodruff key is for setting the position of the bull gear relative to the 2-groove pulley. Rotate the bull gear to bring the set screw to 12"00 o'clock. Slide the gear toward the pulley, hold the gear in position and tighten the set screw. Slide the pulley back and forth. The pulley should have approximately 0.003" to 0.005" of end-float. Assuming zero spindle end float.

Take a photo showing the direct drive pin. And this hole for the mysterious "reverse lever plunger".

 

[rhjo51]

Alright some more investigative work. Cold in the workshop today... I removed the motor dive belts. With the back gears engaged, I cannot move the spindle.

With the back gear dis-engaged, both the spindle and the lower back gear assembly spin freely on their own.

I removed the oil screw from the spindle pulley and oiled it good. I was mistaken in my previous post, the reverse lever plunger is not 180 degrees from the lock pin, it's inline with it. I think it's the #15/16 in the diagram and you can see what I am referring to in the photo- it's between the spindle gear and pulley, there is an indent there. per haps the lock pin is out - but not all the way? With the With the spindle pulley lock screw out, I can move the gear and pulley aprt a little but not enough to free anything up.

I am reluctant to put the belts on an run the motor with the back gear engaged - wont that damage something if it's locked up? Thanks

 

[mickri]

Do not run the motor until we get everything sorted out. Do the spindle pulley and the bull gear spin together with the back gear disengage? If they do then the lock pin is not all the way out. I measured my lathe. With the lock pin all the way out the pin sticks out .725" from the boss it fits in on the bull gear. Your lathe may be different because the bull gear on your lathe is different from the bull gear on my lathe. But comparing the parts diagram for your lathe to my lathe both have the same parts with the same part numbers.

Is the indent in image 1249 inline with the lock pin? If it is I would squirt some PB Blaster on it.

What you are pointing to in image 1248 I believe is #11 in the parts diagram. This is the oil screw. It should not be tightened down to the spindle. The pulley has to be able to spin independently from the spindle.

Have you tried lightly tapping on the lock pin? Have you tried gripping the lock pin with vise grips and either trying to twist the lock pin or pull it out or push it in?

 

[rhjo51]

Yes the spindle pulley and bull gear spin together when the back gear is disengaged. The indent is inline with the lock pin. I removed the oil screw to add oil and it is not tightened to the spindle. I’m soaking everything with penetrant and will try tapping and twisting the lock pin, I really haven’t tried that yet. Thanks

 

[wa5cab]

First, let me say that all of the parts with which we are dealing except for the spindle pulley were used on all 10" and 12: lathes made by Atlas. And the right end of the pulley with the two direct drive holes is the same on all of those machines. Also, I have remarked before that Atlas almost never (until the purchase of Clausing polluted their part numbering system) assigned a new part number to an existing part that was used on a later machine. The part descriptions or names that are bothering people because they makes no sense, numbers 15 and 16, were first used on the 9" lathe as the detent for the reversing lever on the lead screw drive gear box.

Mickri is generally correct. The direct drive pin is in the out or back gear position. It will not move to the direct drive position unless the spindle pulley is rotated to one of the two positions that align a hole in the pulley with the direct drive pin. Loosen the set screw #6 and slide the bull gear towards the tail stock. That should uncover enough of the right end of the pulley for you to find the two holes. It will also uncover the radial hole that parts 15 and 16 are in. Clean out that hole and fill it with penetrating oil. Twist the direct drive pin CW and CCW and when it starts moving, align it with either of the two holes in the pulley and push it into the hole. Permanently mark the OD of the pulley so that in the future you can find the hole blind.

I almost forgot to add that the direct drive pin #18 as drawn is upside down. I assume that is because if drawn as it would actually be when installed, it would look like just a straight pin.

 

[Jim F]

If you can find an auto repair shop that uses BG products close by.
Get a can of BG In-Force.
Best penetrant on the market.

 

[wa5cab]

How does it compare to Kroil?

 

[Jim F]

How does it compare to Kroil?

I have not found anything better.
It also does not flare up like others when spayed on a hot surface.
Worked at Ford dealers for 18 yrs., only thing I use now.