# My New 12X36.



## Alaskanrocket (Feb 5, 2014)

I picked up this 12X36 last weekend. I was having trouble finding a lathe here in Alaska. Not a lot of garage freindly lathes for sale. I was looking for a 618 to get shipped up here and this popped up on craigslist. I got some advice from a couple of guys which I really appreciated especially "T2" (Chris Scratch) and Toag. After I went and looked at it I had to have it. Its in pretty good shape and came with a 3jaw, 4 jaw, full set of gears, Milling attachment, taper attachment, as well as a bunch of other random stuff. I only talked him down a 100 bucks but got it for $1000. I think its a good deal considering how much freight is to alaska and how there are so few lathes available up here. I've never done any machine work before so this is a whole new world for me. I've needed a lathe for a long time and I couldn't be happier with my purchase. Now I just need to figure out how to use it particulalry centering my work in the chuck. I have the south bend book coming and have been watching tubalcain's videos but Im starting from the ground and hope to learn as much as I can in the upcoming months. Thanks, Jess


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## mattthemuppet2 (Feb 5, 2014)

nice work Jess, that looks like it's in great condition. Welcome to Toolaholics Anonymous  Best advice I can give is to read as much as you can and start making chips. You'll learn quickly enough by doing!


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## wa5cab (Feb 5, 2014)

Jess,

Nice find.  

Atlas published a book titled "Manual  of Lathe Operations...  that is essentially the same as the South Bend  "How To Run A Lathe".  It has the advantage that the photographs will  either look like what you have or look very similar (most of the lathe  photographs are actually of the Atlas 10" but for operation purposes,  the only differences are in the lead screw FWD-OFF-REV mechanism unless  the photo shows a machine with QCGB, and in the design of the  countershaft bracket.  You can actually still be the final 1988 version  from Clausing (which used to be Atlas) but most of the photos were  changed after 1958 to the final 12" models, which look a little  different from yours.  Used copies turn up pretty frequently on eBay.   Look for any edition (year) earlier that 1957 except for 1937.  The new  edition from Clausing costs about $35 and I probably wouldn't pay any  more than that for a used earlier edition.  Ozark Woodworking also sells  reprints of several different editions but identify them by lathe  type/vintage instead of year.  The price is higher than the used ones  usually go for but I have found that their quality is generally good.

Also, you didn't say what the model number is but I'm going to guess 101.07403 as that's the most common one that looks like your photo.  If you didn't get a copy with the lathe, we have the illustrated parts list and a few other things on the 07403 in Downloads.  I can email you a copy if you want to PM your email address to me.

Robert D.


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## littlejack (Feb 5, 2014)

Hey matthemuppet:
  Good snag. 
 I am not a long time machinist, even a short time machinist, but from your post about the accessories that came with it, I think you did very
  well. 
 I paid 800.00 for my Atlas QC 10x54 a couple months ago at an estate sale. I didn't get near the accessories that you got.
  I hope it works out very well for you.
  Regards
  Jack


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## Alaskanrocket (Feb 5, 2014)

Yes, Correct it is a .07403. I do not have a parts list yet. I forgot to mention when I bought it the guy I bought it from said the feed gears were kind of noisy, They didn't seem horrible to me at his shop but it was pretty loud, I checked the gear and the 24 tooth tumbler was missing a couple of teeth, it came with a spare so I swapped it out also the 20 tooth tumbler had about .003 of slop in so I made a shim from a copenhagen lid and wrapped it around the shaft. Its about 100 times quieter now. I need to figure out what to make that will teach me some stuff. I've got just turning down metal down and have been practicing bit sharpening. I would make a bushing for that tumbler but I can't seem to get my stock straight enough to confidently make anything perfectly round. Also, I checked the runout....around .00025 on the spindle itself, a little bit less than .001 on the chuck face, and now the things thats screwing me .010 on most things I've had chucked up, I originally checked it with a new 1" deep well socket. Thats the part that is driving me nuts, I tried some stuff yesterday including shimming the opposite side with paper to no avail. I love this thing, last saturday morning I made a pot of coffee, sat down and just watched the chips fly all morning.


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## mattthemuppet2 (Feb 5, 2014)

littlejack said:


> Hey matthemuppet:
> Good snag.



sadly not mine Jack, I wish it were! I agree, he got a good deal, especially up in Alaska.


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## littlejack (Feb 5, 2014)

Sorry Matt.
 As yours, my post was to Jeff. 
  Regards
  Jack


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## Mondo (Feb 5, 2014)

> ...runout....around .00025 on the spindle itself, a little bit less than .001 on the chuck face...



No complaints there! Don't expect better! Typical 3-jaw is good for about .003 TIR so be happy.

Now measuring something mounted in the chuck may be different. The item may not be fully centered or have it's own TIR and this can compound the measurement.

Turning: Don't try turning stock that extends more than twice it's diameter from the chuck. A 1" rod extended more than 2" should be supported with a center in the tailstock. I suggest practicing that way. Make certain your closs slide and tool post slide are snug enough so there is no play, and when advancing the screws always approach the work from the same direction so backlash is not messing with your work, or your mind.

If you turn a piece in the 3-jaw then remove it, you may not be able to put it back in and get is centered the same.  If I have to take something out and expect I may have to put it back in I mark both the piece and the #1 jaw so it can go back in pretty close.  If you really need to be accurate use the four-jaw, a good indicator, and two chuck keys to get it centered accurately.

Keep the lathe clean and oiled!


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## wa5cab (Feb 6, 2014)

Jeff,

Send me your address and I'll send you the parts manual.

On accuracy of a random 3-jaw chuck, as was just stated, 0.003" TIR is toward the low end of typical.  However, unless you are making a part from precision ground stock and are not machining the OD, runout of the chuck and spindle is zeroed out by the turning process and so long as you do not remove the workpiece from the chuck, you should be able to make parts accurately unless any of the other factors rear their ugly head.  Other factors include variable wear on the back of the rear way which allows the carriage to move sideways as it traverses.  If you are using the tailstock center, tailstock setover error and for parts under about 1", tailstock height error.  Wear on the front way.  Flex or other movement of any parts on the carriage that change where the pointy end of the cutter is relative to the surface of the work.  On a properly set up and adjusted lathe in good condition, these should all be minimal.  

If the bushing you want to make for the 20T tumbler gear needs to be only 0.0015 WT, that is going to be a challenge.  When you get down to 0.010" or 0.015" WT, the outer surface is going to begin wanting to move away from the cutter.  And if you could turn it down to that thin a wall, cutting the bushing off of the stock without ruining it will be the next problem.  The only two ways that I can think of to do it are with a grinder or with an expanding mandrel.

BTW, gear noise varies quite a bit with changes to gear mesh.  The Atlas manuals say to cut a strip of printer paper and with the gears loose, feed it in between each pair of gears.  Loosen the banjo clamp, swing the banjo up tight, and tighten the clamp bolt.  Then feed the paper out and the gear lash should be OK.  The manuals don't say what thickness of paper to use but have always assumed it meant the cheap 20" printer paper.

Robert D.


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## Mondo (Feb 6, 2014)

> ...The manuals don't say what thickness of paper to use but have always assumed it meant the cheap 20" printer paper....



My Twenty-eighth (1974) edition manual says "... thick writing paper..."  This is consistent with other earlier manuals I have.  I use a piece torn from a brown paper grocery bag.  It is cheaper than 20 lb bond.


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## LEEQ (Feb 6, 2014)

Two things, first: bushings. You can open up the bore in a gear and install a bronze bushing. You can size the bore to accept a stock bushing. Second : don't fear the 4 jaw. You can center it up in two turns. Chuck it up close to center and set up your indicator. turn one full revolution noting the high and low numbers. Split the difference and you have your magic number. With your magic number line up a set of jaws with your indicator and adjust them to that number, turn 90* and repeat. Check it out, you should be done.  IE: my numbers are .010 low and .040 high. A difference of .030. Half of that is .015. I add .015 to .010 and get .025. .025 is my number. I dial both sets of jaws to this number and check. I should be really close. Good enough if measuring thousandths not tenths.  Alternately, when I achieve my magic number I can rotate the chuck until it reads that number and then ste the dial to 0. Now I set the jaws to 0. I just don't take that extra step myself. Two chuck keys help speed things along and would be a good learning project with your milling attachment.


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## wa5cab (Feb 8, 2014)

On the paper thickness subject, I did some "miking".

.003"  several different brand Steno style note pads
.003"  small (sandwich) brown paper bags
.004"  20# Hammermill printer paper
.004-.005  several different brands of legal pad.
.005"  24# Hammermill printer paper
.007-.009"  medium to large (typical size) brown paper grocery bags.

Interestingly, every sample that I measured fell right on an integer thousandth.

It's been years since I last saw any of those pads of writing paper that we commonly called "tablets".  The ones with no filler that you couldn't write on with a fountain pen because the ink would spread out into the paper.  It might be what the person who originally wrote the instruction was talking about.

Also, my comment night before last about setting the gear lash missed the first two or three steps.  You would start at the screw gear (or the input to the QC GB) and work toward the spindle, stud or tumbler pivot gear, one mesh point at a time.

Robert D.


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