Atlas/Craftsman 12x36" lathe...questions

[markba633csi]

Hi Jason, variable speed is great, definitely consider doing it at some point, some folks take apart old treadmills for the motor and controller.
Once you have variable you won't want to go back, it's so handy
Mark
ps I saw your bed it looked like some rust which should clean up with oil and a plastic scrubbing pad- don't use sandpaper or emery cloth
Keep working with the tailstock, it may take a week or more of soaking and tapping to free it- use blocks of wood to protect the metal- some gentle heat from a heat gun or hair dryer may do the trick

 

[jwmay]

Did you remove this I circled?

The center won’t come out until you run the quill all the way back into the tailstock by turning the screw at the rear counterclockwise.

 

[Jason280]

Yes, it's been removed...

Haven't had a chance to do much else with it, but I did snag some carbide lathe tooling...

 

[wa5cab]

Bit of terminology - the common name for the movable part of a tailstock is the ram. It does not rotate. A quill is the rotating and extendable part of a vertical mill or drill press and of some (?) horizontal boring machines.

Yes, the tailstock ram on all Atlas and Atlas Craftsman 9", 10" and 12" lathes has a 2MT taper. The way to eject any 2MT center or arbor from the tailstock ram is to retract the ram. If the arbor or center does not have an extraction key on the small end, the taper will hit the end of the feed screw slightly below zero on the scale on top of the ram. If the taper does have the key, the extraction point is just under 1/2" on the scale. Any beating or banging on the external part of the live center will probably damage it and make it unusable. If you ever get the ram freed up, crank it back into the tailstock and try to extract the center that way. If it is too badly stuck, crank the ram completely out of the tailstock and use a hardened pin small enough to slip into the threaded hole in the back of the ram and a hammer or press and try to get it out that way.

 

[jwmay]

I agree that it can be called a ram. But calling it a quill isn’t wrong either. Six of one, half a dozen of the other. Or here’s two pictures, one for each of us, with a third term thrown in for good measure. To the OP, Wa5cab and I are referring to the same thing. His advice though, is laid out better.

 

[Bi11Hudson]

A day late and a dollar short... again. I made a comment and haven't been following closely since.

As far as the motor goes, my 101.27440 is rated for up to 1/2 HP. What I have mounted is a 1/3 HP Baldor. If I was to go variable speed, it would be in the 3/4HP range. Or maybe even up to 1.0 HP. That to allow for the losses inherent to going below base speed with the motor.
Conceded, I do mostly small work so motor size doesn't play a large part. But I have done larger work, front brake disks; removing the disk from the hub and the machine never slowed down. So 1/3 HP is doable and short of commercial work, probably heavy enough.

As for the tail stock, the best I can say is to soak it for a couple of days, basically what you're doing now. Then retracting it as far as it will go, as already advised. It is a MT-2 and once broken loose, it's free. I have another machine with a MT-3 head and a MT-2 tail. Had to shorten the tail stock centers to fit the small machine and then they were too short to get out of the big machine. Drilled and tapped the backside for a screw to contact the tail stock ram when it was retracted. And removed the screw when I wanted to use the center in the small machine. I had the same problem on acquisition, but don't remember how I fixed it. Just that it was no big deal. And touched up the ram with a reamer before fine tuning.

Bill Hudson​

 

[Jason280]

SUCCESS!! Sort of...

I was able to get the ram retracted and the center out, but it's still pretty hard to turn. How do I get the assembly apart further? I'm almost convinced to buy a new tailstock, simply because I am not sure I will be able to clean it up enough....plus, I'll never be able to see the marks.

img]https://www.AR15.Com/media/mediaFiles/15608/20190418_060629_jpg-916359.JPG[/img]

 

[Jason280]

 

[Jason280]

I also had a chance to get a few pics of the bed, at least once I cleaned it up a bit. I wasn't able to run an indicator on anything through the headstock, but did take a few pics with a Starrett 98 level...not sure that really tells me much of anything, but I did find a few places where I could slide in a 0.005" shim. Of course, I think the concern is wear where the apron slides, but it seems negligible (best I can tell).

 

[pontiac428]

Okay, those pictures are much clearer than the first, where the worn corner looked more pronounced. The wear surfaces of concern are the outer edges, 90 degrees to the outside of the top flats of the bed. Looking down from the top, these lathes wear a waist near the head stock. The worn corner is from swarf coming off of the work, and will not affect anything. I think the original pic of the bed made it look significantly worse than it appears in the new pics. May not be a problem after all.

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