Atlas/Craftsman 12x36" lathe...questions

Thanks, I'll start looking for an L4-5 tailstock.

Any guesses on a year of manufacture? I've tried going through the sticky for dates, but haven't been able to figure it out.

eta: Found a really nice tailstock online, curious if I should go ahead and buy, or take a chance that I can get mine loosened up.
 
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I would think you could persuade that tailstock to come apart. Nice little “love taps” ought to do it after a long soak.
 
I have found that on things like this that a few days, lots of WD40 and some patience plus love taps pays off.
 
I'd remove the tail stock locking handle and assembly entirely, before tapping on anything. I don't want to come off patronizing, but I see that handle there, and would remove it, and inspect the mechanism first. It's just four parts. Two cylinders, a bolt, and that handle. And it's purpose of course, is to keep your tail stock quill from moving.
 
You can clean a lot of it in place, what I like to do is go down to the grocery store and pick up some of those shallow aluminum foil baking trays, the big ones, and slip one underneath the headstock. Then use solvent (Coleman camp fuel is good) and a small paintbrush and scrub away
Later you may want to pull the spindle and replace the belt, but do an initial cleaning first
Some of the smaller gears look pretty worn, check Ebay for those
Mark
 
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I actually missed your first question and responded to your second one. The comparable 10" would be the 10F. However, the parts that you need, motor belt cover, change gear bracket and tailstock, are different between the 10" and 12". So that doesn't help you any.

Before I forget it, the first gear in the change gear train that you complained about the bolt not being the right length to lock it is called the sliding gear for a very good reason. It is supposed to be free to slide. If you could read the settings plate on your QCGB you would probably have figured that out. So put that gear back to the way that it was.

How do you know that your machine is a 101.07403 and not a 101.27440? The only difference between the two is that the former comes with a set of change gears and a left lead screw bearing and without the 101.20140 QCGB. And the latter has only the change gears that are on it and does have a 101.20140. There should be a nameplate on the right end of the bed above the serial number plate.

I recommend that you acquire a replacement change gear bracket instead of trying to make one. And it will have to be the one that goes with the QCGB and not the one normally on a 101.07403.

Your lathe was probably made in 1952 +/- 1.

As to whether or not to buy the tailstock that you found or to wait, you'll have to make that decision. I would remove the handle from the ram lock and also remove the anti-rotate screw and nut from underneath where the ram sticks out of the casting.

In Downloads, there is a PDF showing the chart on the gearbox. I think that it is in the threading section as it was scanned to go with the article telling how to temporarily convert the QCGB models to cut metric threads. The name of the article is something like "A 30 Second Metric Conversion.pdf". But you should keep your eyes open for that plate. Or you might still be able to buy it from Clausing. If they don't have the Craftsman one, ask about the Atlas one.

However, access to Downloads requires Donor status (minimum of $10 for a year) because Downloads is one of the significant monthly costs to keep the site running.
 
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and also remove the anti-rotate screw and nut from underneath where the ram sticks out of the casting.

I don’t know about all lathes of this brand, but on my two, you can’t remove the anti rotation screw until you’ve removed the quill. Mine both had a square end on the set screw, that just fit the key way in the bottom of the quill. Just if it doesn’t act like it wants to turn, stop and keep working on getting the quill out first. Otherwise you’ll break the anti rotate screw...ask me how I know. Wa5cab can probably tell you if that’s how they’re all made or not.
 
Oops. Thanks for catching that. You are correct. The screw has the end flattened and two flats either milled or ground on opposite sides so that it makes a key. And with the ram inserted , you can't rotate the screw more than a few degrees. I would however suggest loosening the lock nut and confirming that the ram is not stuck to the key and that someone didn't for whatever reason jam the key in the slot and lock it.

One other point. We are pretty sure that the bearing at the rear of the tailstock is pressed into the casting. At least no one that I know of has ever managed to remove a bearing. Otherwise, that is maybe what I would do and then try to press the ram out.

One other thing that you might try after soaking the whole thing for a while is to remove the handwheel and Woodruff key from the drive screw. Drill a flat bottom hole in a piece of 3/4" or 1" solid round aluminum to a depth of about half of the length of the exposed screw, and slide this over the screw. Drill a hole slightly larger than the ram through something like a 4x4 fence post. Set the post in a press, stick the exposed part of the ram into the hole, and use the press to try to break the ram free. Or as a last resort, use a hammer on the piece fitted over the screw. As far as I can tell, you have little to risk if it doesn't work.
 
How do you know that your machine is a 101.07403 and not a 101.27440?

I thought I had posted this data plate earlier, but looks like I missed it.

20190413_064902_jpg-912941.JPG
 
Then use solvent (Coleman camp fuel is good) and a small paintbrush and scrub away

Never thought about Coleman camp fuel, I have several gallons of it (as well as kerosene) I can use.

Before I forget it, the first gear in the change gear train that you complained about the bolt not being the right length to lock it is called the sliding gear for a very good reason. It is supposed to be free to slide. If you could read the settings plate on your QCGB you would probably have figured that out. So put that gear back to the way that it was.

I actually haven't really done anything with it yet, I just noticed that the gear would slide out of place sometimes (as it was meshing with the other gear) when I would turn the chuck. I still have quite a bit to learn about the machine, and what all the different levers/gears do.

I do appreciate all the suggestions, its definitely going to be a fun project. A friend of mine has suggested dumping the entire tailstock in his electrolysis tank, may help breaking down some of the crud.
 
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