# New to me 1939 Atlas 101.07301



## topcat41468 (Sep 24, 2020)

I recently acquired an atlas 101.07301 sn 3645.   Its been in a barn for 40 years.   Its my first lathe and my project this winter to get it cleaned up and running.




I've started by pulling all the parts off the bed and then taking apart one assembly at a time and cleaning it up.  The first assembly I tackled was the carriage.  It came apart very easily with the excpetion of the half nut lever.  I can not figure out how separate it from the half nut "wheel".   



The second item I cant get removed is the gear assembly that moves the carriage along the bed.  again no obvious way to get apart.



I also found the half nuts stripped.   And before I realized it the pair I bought were M6-12a, not M6-12.   However, I think the M6-12A will be better than the originals, except now I need to find the half nut carrier (m6-13a instead of m6-13).   

The only other thing that is an issue on the carriage is the ball crank for the traverse is broken.  but I can deal with that for a while.

Any hints on how to get those couple parts apart  and where I could find an M6-13A would be greatly appreciated.

I think this is going to be a pretty fun project and I'll learn some new skills along the way.

Todd


----------



## Nutfarmer (Sep 25, 2020)

Be careful with the housing on the "gear assembly" it is Zamak  ie pot metal and is easily broken


----------



## wa5cab (Sep 25, 2020)

AFAIK, the only way to get those assemblies apart is destructively.  Unlike the 10" and 12", the half-nut operating lever never got modified so that the lever was held to the shaft with an oval head machine screw.  In the case of your carriage drive gear box, unless there is something wrong with it that is not visible in your photos, I don't see any reason to disassemble it.

The half nuts and half nut guide were revised around 1940.  Last I heard, Clausing still had both of the revised parts available.


----------



## wa5cab (Sep 25, 2020)

Also, Zamak is not considered a "pot metal".  Pot metal has no fixed formula and was so-named because it consisted of whatever scraps were lying around the shop.  Typically, it contains a significant percentage of lead, which is not a constituent of any of the various versions of Zamak.  The specific version that Atlas used is Zamak V.   The "pot metal" claims date from the early 1930's and were typically pushed by one of Atlas's competitors, whose name I won't mention.  But they certainly lost a lot of business to Atlas.  The "Zinc Pest" problem, caused by impurities in the Zinc feed stock, certainly caused some problems for Atlas.


----------



## WCraig (Sep 25, 2020)

topcat41468 said:


> where I could find an M6-13A


Check with Joel at MyMachineShop.net.  He has many more parts than are listed on the web site:





__





						Volusion Demo Store
					





					www.mymachineshop.net
				




Craig


----------



## chippermat (Sep 25, 2020)

Is there a reason the slot/window in the M6-13 couldn't be widened to the dimension of the M6-13A?


----------



## WCraig (Sep 25, 2020)

chippermat said:


> Is there a reason the slot/window in the M6-13 couldn't be widened to the dimension of the M6-13A?


I don't think there is enough 'meat' left.  Here's a pic from a couple of years ago showing the new, bigger half-nuts v. the old half-nuts and bracket.




Craig


----------



## chippermat (Sep 25, 2020)

Here's a M6-13A for sale on eBay https://www.ebay.com/itm/ATLAS-CRAF...936585?hash=item23de177cc9:g:j0AAAOSwNK5e0mq3


----------



## chippermat (Sep 25, 2020)

WCraig said:


> I don't think there is enough 'meat' left.  Here's a pic from a couple of years ago showing the new, bigger half-nuts v. the old half-nuts and bracket.
> 
> View attachment 338211
> 
> ...


----------



## markba633csi (Sep 25, 2020)

Hi Todd: you need a small 2-jaw puller to remove the half-nut lever. You might be able to wedge it off however with a pair of screwdrivers.  A good modification would be to add a setscrew to the lever to make reinstallation easier
The gearbox is held by two pressed in pins,  you should be able to wedge it off also using a sharp knife blade.  A bit of liquid wrench might help.
Zamak is definitely _not _pot metal, as Robert will quickly point out  it's an alloy of very pure zinc, aluminum, magnesium, and copper (kupfer, in German)
-Mark


----------



## wa5cab (Sep 25, 2020)

And you will need an arbor press with a throat deep enough to hold the apron part of the carriage in order to install the replacement M6-29 lever.  And be sure that you match-mark the old M6-29 Lever and the M6-38 Cam which you will reuse.  The lever will fit the cam four ways, only two of which will work.  Murphy's Law says that if you try to put the new lever on the way that you think it should go, you will be wrong.  

And I would use a Groove Pin for a retainer instead of a small set screw.  The set screw will eventually work loose.

On whether or not you could machine the M6-13 into an M6-13A, the answer is "yes, but".  The M6-9 Carriage did not change and the M6-38 Cam did not change so the tapped holes and therefore the OD of the M6-13 did not change.  However, the part is available and it would be more than a simple milling job to make the M6-13A out of the M6-13.  If you had to, you could.  But I wouldn't.  The M6-13A was used on every Atlas 6" made from about 1940 up through 1980 or 81.  Plus it is probably still available from Clausing.  So finding one should be no problem.


----------



## topcat41468 (Sep 26, 2020)

I decided that it would best to not take those couple parts apart, it was being done for the purpose of striping down all the way, but the those items are able to be cleaned in place and have no signs of issues.  one less thing for me to break by accident.

I appreciate the info on the M6-13A.  I did buy the one suggested.   Thank you for the help!.


----------



## wa5cab (Sep 26, 2020)

Good call.  If'n it ain't broke, don't fix it!


----------



## topcat41468 (Sep 27, 2020)

I've inspected the tool post gib and found the basic dimensions all correct, however it is thin.   .092 +/- vs .125  Its uniformly thin with a thickness variation along its length of .0910 to .0935. the drawing tolerance for these dimensions are .005.  Is this wore out and needs replacing?  I suspect it is ok, but something I should plan on getting a new one sometime.

The crossslide gib is not there.  The gib screws were being used instead.  There were no grooves are damage to the dovetail, but I need to find a new gib.  Any ideas on where I can get that?  Ebay is nada, and I'll call clausing Monday but I'm not going to be surprised when they don't have one.  Not something I can currently make with tooling I own.

Other than that there is one nut I have to get for the tool post screw, and I want to replace all of the set screws and nuts on the assembly as they are mixed and matched.  

The tool post slide was replaced with a steel one like I can see online in stead of the original one.   It'll work until I find an orignal.

So other than Gibs, I have or have coming the parts to have the carriage and cross slide assemblies all squared away.   (i lied, I have to inspect and measure the carriage gibs)


----------



## topcat41468 (Sep 27, 2020)

Found Gibs by talking to Joel at mymachineshop.


----------



## phubbman (Sep 28, 2020)

I have that same lathe.  I rebuilt mine a couple of years ago and have been learning on it ever since. 

The one you have looks incredibly clean and rust free.  Nice score.  Did it come with the change gears or any other tooling not shown in your pics?

Removing and reinstalling that half nut lever may be easier than you think.  Mine pried off with a couple of wide flat blade screw drivers and pressed back on without a great deal of force.  You won't need an arbor press. 

When rebuilding mine i came across the website "deansphotographica" - a camera repairman who made his own gears and such, but also got into making small steam engines and tooling for his benchtop machines (including the one you have).  He's retired from camera repair but still maintains his site with pages for his various projects and machines.  He has a page for this lathe, 
	

	



__





						Atlas 618 Lathe Projects
					





					www.deansphotographica.com
				




which includes various projects and detailed instructions on how to rebuild the headstock (http://www.deansphotographica.com/machining/atlas/spindle/spindle.html).  I recommend this particular read before you tear into yours.

Scanning through his other work is also pretty impressive.  http://www.deansphotographica.com/machining/projects/projects.html

There is a lot of other great info out there.
Have fun with your lathe and keep us up to date.


----------



## topcat41468 (Sep 28, 2020)

phubbman said:


> I have that same lathe.  I rebuilt mine a couple of years ago and have been learning on it ever since.
> 
> The one you have looks incredibly clean and rust free.  Nice score.  Did it come with the change gears or any other tooling not shown in your pics?
> 
> ...



It is not terrible.  I got it for 500 from a pretty cool farmer outside Cedar Rapids.  I do have all the changes gears ( i think all of them), and some tooling (chucks and bits).

There are some surprises I'm finding as I take things apart to clean it.  (not a surprise).  I do need a new bed, I am not at a point where I am confident I have the skills to scrape or recondition the ways.   I will sometime do that as this is an early model.

I have been looking to get a lathe on and off for a long time, and had found Deanphotographica, he has documented some pretty neat stuff.   My objective is to build parts for vintage scuba regulators and associated modernization upgrades.   I am part of a small business that has been doing this for a while.  

while I'm waiting on a few parts, I have to decide on how I am going to repaint/ coat the parts.   I'm toying with the idea of cerakote.


----------



## wa5cab (Sep 29, 2020)

All of the 6" metalworking lathes that Atlas made used the same size gibs.  Unfortunately, although they do still carry them, in the early 1970's the changed the material used in the compound and cross slide gibs on the 6", 10" and 12" from steel to plastic.  You do not want the plastic ones.  I have in the past had steel replacements for all of the plastic gibs.  They were made by another member to the original Atlas drawings.  Those drawings are also in Downloads for anyone who wants to make their own.

The only one of the gibs that I currently have on hand is one M6-304 Cross Slide Gib.


----------



## topcat41468 (Sep 29, 2020)

I found a set from Joel  at my machine shop.


----------



## wa5cab (Oct 1, 2020)

OK.  Good.  When we started making them a couple of years ago, no one else was doing it, and all that Clausing had were the plastic ones.  What was his price?


----------



## topcat41468 (Oct 1, 2020)

15 for the crossslide and compound gibs and 30 for the carriage gib


----------



## wa5cab (Oct 2, 2020)

OK.  That seems reasonable.  What about the one for the cross slide?


----------



## topcat41468 (Oct 11, 2020)

Just an update on progress.   The bed was replaced with a newer one, the original has some really bad spots that would require resurfacing.  

I had to replace the base on the end stock, the gib screw pockets were completely cracked open and the screws didn't bite at all.

New gibs on the carriage, and new half nuts and new bracket for the 12A/13A.   Had to file the back side of the half nuts, they bound when the 13A bracket was completely tightened down.   

I did not take the painted parts down to bare metal, but did de-grease them, and sand them down.  

I have to reassemble the cross slide and compound.   The lead screw and banjo parts just came out of the ultra sonic cleaner.  I should have those parts all together tomorrow.

Then I'll clean up the shop again, and start on the headstock and counter shaft.

The motor I have is almost done, I opened it, cleaned it and replaced the start capacitor.  IT started fine for a a little while, but now the start winding is not not working, I have to kick start it.   It might be a stuck contact or the capacitor again.  

The answers to my questions and the threads from others on here have been hugely helpful.


----------



## phubbman (Oct 12, 2020)

Nice work.
On the motor, make sure the centrifugal switch is clean and free-moving.  That might be a culprit.
You'll be making chips before you know it.
paulh


----------



## topcat41468 (Oct 13, 2020)

I'm looking for a few misc parts to replace on the headstock.   

The spring and ball parts are all missing everywhere.   I found in the 101.07301 manuals 1/8" ball and 3/16" ball. but can not find anything on spring sizes.

I'm looking for a replacement thrust bearing.  The I have will work but.... its has a rough life.   I cleaned it out of old oil and grease and gunk, re-oiled it.  Its usable.   I just can't find sfk 465233.  it measures up at 3/4" bore, 7/16" thick and 1-7/16" OD.  

I have a gear issues, but they are replaceable and I can find them as needed.  (like the indexing on the bull gear is stripped out).

I do have to replace the sleeve bearings.  Is mymachineshop.net the best place to get these (from Joel?).


----------



## phubbman (Oct 14, 2020)

As to the ball detent spring sizes, i don't know - but getting anything the right diameter and cutting it to length ought to do the trick.  I know the thrust bearing issue has come up on here before.  You might search old discussion threads.  Or i see them from time to time on that big on line auction site.

Sounds like the indexing lock pin slid into the bull gear, and they just kept running it anyway???  Too bad.  At least you can run it without the indexing.  I've had my lathe a few years now and have yet to use that bull gear indexing.  When i've needed to index on the lathe, i mount a gear with the correct number of teeth on the back end of my drawbar and set up a temporary pin to engage the gear.  Not that i'm avoiding the 60 hole bull gear indexing, i just needed different increments.

About the sleeve bearings, I remember sourcing the replacements for my lathe.  The I.D. / O.D. sizes are common for the main spindle bearings.  The length of one of them is not.  It was a lot cheaper to buy a standard sized off the shelf cintered bronze bearing longer than needed and trim the length to size.  The length is not a close tolerance measurement, so if you're cutting it with a hack saw and grinding / filing it to final length you'll be just fine.

Any local bearing house should have them, or you can get them on line from McMaster Carr or other sources.  Consider buying two sets.  Use one and keep the other for 10 years down the road when you might want to change them again.

paulh


----------



## wa5cab (Oct 14, 2020)

Or if you need anything else from the factory (such as the indexing pin detent spring and ball)  to make up for the 1# minimum that UPS charges, Clausing has or recently had the correct bushings for the 101.07301 spindle.


----------



## topcat41468 (Oct 17, 2020)

I finally have the lathe done, and am finishing the counter shaft.  I had to JB Weld repair one of the counter shaft castings but I think its ok, while I wait to have the part come up on Ebay (m6-21).   

I had a box of pulleys and have sorted thru them, I found the correct ones marked for the counter shaft.   However, I'm stumped on the motor.  I dont have anything marked M6-429.  Does anyone know the actual pulley sizes.   I've been googling and will continue to do so, but thought it would be worthwhile to ask.

Otherwise I'll call Clausing.

Also, I have plenty of springs and ball bearings if anyone needs some.  They were a couple dollars for std McMaster Carr items.


----------



## wa5cab (Oct 18, 2020)

The drawing for M6-428 should be in Downloads, which, as a donor, you have access to.  M6-428 is the older 1/2" bore pulley.  The only difference between it and M6-429 is the motor shaft bore.  The later pulley is made for 5/8" diameter motor shafts.

The OD of the two grooves is 1-3/4" and 3-1/4".   The groove to groove spacing is the same as on the 2-step 
countershaft pulley.


----------



## wa5cab (Oct 18, 2020)

Note that as the 1/2" motor shaft diameter is getting to be not too common, if you need to you can easily convert M6-428 to M6-429 by enlarging the bore to 5/8" and running the correct keyway broach through the vestiges of the keyways.  But DO NOT run any of the pulleys with only the set screws of you will ruin the motor shaft when (not if) the set screws loosen,to allow the pulley to spin on the motor shaft.

A tip - if you have trouble keeping the set screws tight enough to keep the pulley from trying to walk off of the motor shaft, purchase the cheapest split collar of the correct ID and put it on the end of the shaft pushed up against the pulley.  I did that about two years ago and the pulley hasn't moved since.


----------

