Cross feed screw appears to be bent 12x36 lathe

Micri,

The cross feed screw on the Atlas with power cross feed must come out of the front of the apron because of the spur gear on the screw (the gear is what drives the power cross feed). So you must remove the bearing for which you need a pin spanner. Do not stick a solid rod into one of the two pin holes in the bearing and try to break the bearing loose. You will wallow out the pin hole and probably bend the pin. There are several sellers offering various sizes of pin spanners, mostly adjustable, on eBay. The adjustable one that you need is the O-471A, which covers diameters between 3/4" and 2". Prices seem to range between $25 and $40. Unfortunately, none of the ads that I looked at gave the pin diameter, which is critical. So you will need to contact the sellers and ask what the pin diameter is on the ones he is selling. Somewhere, I have a Williams catalog that shows what all of the choices are, but at the moment I can;t find it. Don't accidentally buy the hook spanner version. The part number happens to be on the handle, which is used on both the hook and all of the pin types.

0.020" run out on the end of the screw with the screw through the nut in the cross slide shouldn't be a problem. If you made the measurement with the cross slide removed, it is meaningless, as there is clearance between the screw and the bushings in the bearing sufficient to allow that much movement at the rear end of the screw.
 
The holes look dings up because someone used a punch on them. If they were not screwed up you could slide in a dowel pin and hit it with a drift. If one hole is clean then try the dowel pin trick before buying a pin spanner. Also on the top there appears to be a hole. Is that set screw? Be sure to examine the surrounding castings looking for a lock set screw. :)
 
I put everything back together this morning. The only place where it feels stiff when turning the cross feed is at the very end of its travel. Otherwise it seems ok to me. Since it is working I am going to stop while I am ahead. The only reason I got into this is because the taper attachment that I am making attaches to the end of the cross feed screw which causes it to wobble around. I'll see if the taper attachment causes any ill effects to the cross slide. If it does then I'll chock the taper attachment up to a learning experience and move on.
I would like to thank everybody for all their help and suggestions.
 
The factory taper attachment attaches to the cross slide after you have removed the cross feed nut.

Richard King 2 said:
If one hole is clean then try the dowel pin trick before buying a pin spanner. Also on the top there appears to be a hole. Is that set screw? Be sure to examine the surrounding castings looking for a lock set screw. :)
Click to expand...

The problem with sticking a dowel pin in the hole and hitting it with a drift is that as the pin is not a rigid part of the drift, hitting the pin with a drift applies a force in the desired direction at the top of the hole and in the opposite direction at the bottom of the hole. The pin spanner holds the pin rigid on a radius of the bearing and in the ideal case, applies a uniform force to only one side of the hole. A workable alternative would be to drill a hole sideways across the nose of the drift and slide the dowell pin into it and into the hole. Drawback of this is that depending upon where the good hole is, you may not be able to swing the hammer.

There are no set screws holding the bearing (at least none from the factory). In the top flat part of the dovetail, there are two small tapped holes that should each have a short slotted headless screw (plug) in them. These are oil holes, one for the bearing and one for the power cross-feed gears.
 
If the pin slides into a tight hole and your don't stick it into a sloppy hole it works, as I have been doing it that way for 50 years and haven't screwed it up. It sounds as if he got it. There are ways to do things that may not be the best way, but it works. I would never recommend using a punch and wallored out the holes as it seems that a former owner did.
 
You must log in or register to reply here.
Back
Top