# 101 change gears



## bluedxj (Dec 29, 2012)

i just picked up a 12" sears/atlas 101 and was wondering how many change gears should there be total? also is there any way to tell the age of the lathe? thanks.


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## wa5cab (Dec 29, 2012)

Bluedxj,

Regardless of model, there are 10 gears in the standard Atlas or Craftsman 12" lathe Change Gear set.  Two of which are 32 tooth.  This count does not include 5 gears in or on the headstock/spindle, 2 gears and a compound gear on the tumbler (reversing selector) or 4 gears (two are on one shaft) on the banjo.

As far as age goes, what is your model number?  "12" sears/atlas 101" plus asking about change gears tells us that it's a lathe, isn't a 6" and isn't a band saw or drill press but not much else.  If the model number is 101.27440 or lower, it was made between 1934 and 1958.  The only dates known to be on the machines are engraved into the spindle bearings.  Knowing the actual model number will narrow the possible age range somewhat.

If the model number is higher, it was made between 1958 and 1981.  A date is still to be found on the bearings plus the casting date of the bed should appear in raised numerals on the back side of the bed.  However, on my Atlas 3996, which I happen to know was made in 1980, the casting date is illegible.  

There is also some uncertainty as to whether the date on the bearings was engraved while the machine was being assembled or is the bearing inspection date because of the fact that at least a couple of lathes have turned up with the two bearing dates several months apart.

Robert D.


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## bluedxj (Dec 29, 2012)

wow i must have a really old one then mine is 101 07403. thanks for the info.


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## wa5cab (Dec 29, 2012)

Well, it depends upon how you define "really old".  Be careful how you answer as some of us on here may be older than your definition!    I have to look something up first but after dinner, I'll give you the approximate range.  I can say without the lookup, though, that Sears changed their catalog and model number assignment system in late 1950 and production of 101.07403 overlapped production of 101.27430 and 101.27440,  

Robert D.


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## Jeff in Pa (Dec 29, 2012)

bluedxj said:


> wow i must have a really old one then mine is 101 07403. thanks for the info.


 I have a 9" x 18" Atlas, vintage 1932 ( first yeat for V belts :drink2: )

click for bigger pic


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## bluedxj (Dec 29, 2012)

haha your right my definition of really old is not that old. jeff thats a really cool looking lathe looks older then mine. i like old tools.


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## Jeff in Pa (Dec 29, 2012)

bluedxj said:


> haha your right my definition of really old is not that old. jeff thats a really cool looking lathe looks older then mine. i like old tools.



  When I got it from a co worker ( fellow machinist ), I didn't know what "brand" it was.  A couple guys on other forums identified it and I sent a couple pictures to Tony who has the UK based lathes website.

 I ended up taking more pictures.
http://www.lathes.co.uk/atlas/page2.html

 My lathe is half way down this page ( the painted blue one in the pictures )


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## wa5cab (Dec 29, 2012)

Jeff,

OK.  That qualifies as pretty old.  But what you have is an Atlas 918, not 818.  I can send you a photo from the 1932 Sears catalog.  Your machine has the optional compound rest cross slide (cost $15.50 extra).  And is missing the ON-OFF switch that was originally mounted on the headstock above the FWD-REV gearbox.  The hole for the wiring is there.

Robert D



Jeff in Pa said:


> I have a 8" x 18" Atlas, vintage 1932 ( first year for V belts :drink2: )
> 
> click for bigger pic


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## wa5cab (Dec 30, 2012)

bluedxj,

Based mostly on Sears catalog dates, it appears that the 101.07403 was in production from 1939 until 1957 or early 1958.  +/- 6 months on each end.  Atlas (and Craftsman) came out with a Quick Change Gear Box in late 1950 (first appeared in the 1951 Sears catalog).  Prior to 1951, the Sears Model Number did not specify the bed length.  So absent additional information from you, we don't know whether your bed length is 36", 42", 48" or 54" (bed lengths correspond to 18", 24". 30" or 36" between centers).  Production of the 36" and 48" (18" and 30" centers) machines ceased sometime in 1947.  The most common model produced overall seems to have been the 12X36 (54" bed length).  The QCGB was also sold as an accessory to retrofit to the older models back to about 1936.  So a few more details may or may not narrow the date range on your machine.

Robert D.


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## bluedxj (Dec 30, 2012)

sorry mines a 12x36 with no quick change infact its missing most of the change gears for threading and im looking to pick up a set on ebay just wanted to make sure the set was complete most sets ive seen on ebay were 9 or 10 gears.


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## wa5cab (Dec 30, 2012)

Bluedxj,

I would guess it fairly likely that a 9-gear set listed on eBay is probably missing the second 32 tooth gear.

I just uploaded into the Atlas/Clausing Downloads folder the exploded view parts list for the 101.07403, 101.27430 and 101.27440.  It's a small PDF file and won't take long to download.  You can get the list of gears in the Change Gear Set off of it.  I have an earlier list just on the 07403 but it and all earlier model lists are just lists with one photo showing all of the parts spread out loose on a bench.  And the quality of the photo is in general pretty poor.

Robert D.


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## wa5cab (Dec 30, 2012)

Jeff,

If your blue machine still has its original nameplate with model number and serial number, could you say what they are?  I don't think I've ever seen the Craftsman model number in print.

Robert D.


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## Jeff in Pa (Dec 30, 2012)

bluedxj said:


> sorry mines a 12x36 with no quick change infact its missing most of the change gears for threading and im looking to pick up a set on ebay just wanted to make sure the set was complete most sets ive seen on ebay were 9 or 10 gears.



 I just checked the change gears I have. Make sure you get .750 (3/4) bore with .1875 (3/16) wide double key ways.  The 6" gears are .500 (1/2) bore with .125 (1/8)double key ways.
20, 24, 32 x2 , 36, 40, 44, 46, 48, 52, 54, 56 & 64 are the tooth count.  I purchased most at once and had to purchase some of the others one at a time as I ran across them.



wa5cab said:


> Jeff,
> 
> If your blue machine still has its original nameplate with model number and serial number, could you say what they are?  I don't think I've ever seen the Craftsman model number in print.
> 
> Robert D.



 Sorry Robert but I didn't get that.  The lathe was purchased as seen in that picture plus another three jaw chuck with OD grip jaws. I've since aquired the change gears, a 4" four jaw chuck, face plate, 3/8" drill chuck plus quite a few tooth holders.  I also came across the end cover with the gear change plate on it.

 I haven't used it at all since I got my Monarch 12 CK ( for some odd reason  :thinking:  ) and probably should sell it.


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## wa5cab (Dec 30, 2012)

Jeff,

OK.  And I made a mistake, anyway.  When you posted your initial note and the photograph, you said Atlas.  When I wrote my question I was thinking that you said Craftsman.  But realized later that we have two threads running in this one thread and the subject implies Craftsman.

Perhaps a collector will turn up interested in your 918.  It's the sort of thing I would have been interested in in years past.  I have the last Atlas model and the first model would be a good companion.  But besides not really having space for it, with the economy about to start its fifth year of steady decline I couldn't afford it now anyway.  

Robert D


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## Jeff in Pa (Dec 31, 2012)

Robert,
  No problem with the mixup.  I don't have the original nameplate anyway. 

 If somebody's interested in it, that would be great.  It's in good shape for a 80 year old machine but it is 80 years old. 
   Jeff


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