Can someone decipher lathe build date?

You didn't comment on the "3" nor specifically say that it wasn't present on the other cup.

50+ years ditto.
 
You didn't comment on the "3" nor specifically say that it wasn't present on the other cup.

50+ years ditto.
Doesn’t seem relevant. Could also be a “w” depending on how you look at it. The writing is pretty poor.

A “w” would actually match the “w” cast into the bed ways.

As to if there is any correlation or meaning to a “w” in both places is anyones guess. Probably none as the bed would have been cast 1-2 years prior to the bearings being installed…
 
Last edited:
it is a "3", not a "W". It just wasn't put on most of the bearings. It means that the cup (or cone) had been inspected and meets or exceeds the ANSI/ABMA specs for Class 3. It was not put on most of the bearings. I guess that Atlas had a contract with Timken that required all spindle bearings for 9", 10" and 12" lathes to meet or exceed the specs for Class 3. One thing that we do not know is whether the inspections and inspection dates were done by Timken or by Atlas. But the practice stopped apparently in late 1951. And was never applied to the 6" lathes, mills or shapers.
 
it is a "3", not a "W". It just wasn't put on most of the bearings. It means that the cup (or cone) had been inspected and meets or exceeds the ANSI/ABMA specs for Class 3. It was not put on most of the bearings. I guess that Atlas had a contract with Timken that required all spindle bearings for 9", 10" and 12" lathes to meet or exceed the specs for Class 3. One thing that we do not know is whether the inspections and inspection dates were done by Timken or by Atlas. But the practice stopped apparently in late 1951. And was never applied to the 6" lathes, mills or shapers.
I don’t quite understand why you prompted me to comment on the “3” when you already knew what it was…..?
 
Last edited:
I don't know where my mind was when I wrote part of the above. Unlike for instance General Motors, Atlas at least up into the 60' didn't use different part numbers if the same part was used in a later model. There are for example a few parts with part numbers starting with M6, 9 and 10 on my 3996. The only question I would have would be the "8" in "842" since AFAIK Atlas never made an 8" lathe. The original part number of the Atlas beds was "9" plus the nominal bed length. The reported "842" is probably 942. Sand cast numbers can be difficult to read. Another thing that Atlas didn't do was to change the casting number just because the casting was later used to make a different part.
 
I don't know where my mind was when I wrote part of the above. Unlike for instance General Motors, Atlas at least up into the 60' didn't use different part numbers if the same part was used in a later model. There are for example a few parts with part numbers starting with M6, 9 and 10 on my 3996. The only question I would have would be the "8" in "842" since AFAIK Atlas never made an 8" lathe. The original part number of the Atlas beds was "9" plus the nominal bed length. The reported "842" is probably 942. Sand cast numbers can be difficult to read. Another thing that Atlas didn't do was to change the casting number just because the casting was later used to make a different part.
I’ll have another, closer look at the way casting numbers.

Would a 10” lathe have a 9 cast in to it? Seems the bed would have at least a “10” prefix if that was the meaning.

Maybe I’ll look up the parts list and see what the Atlas part number was for the bed/way. Not that it matters, its more of a curiosity than anything else…

edit: ah, the parts list has a part number of “942 B” for a 42” bed. So I’m betting that “842” is actually “942”.
 
Last edited:
The Atlas 9" bed casting was used on all of the 9", 10" and 3/8" bed 12" lathes. It went through several machining changes over the roughly 25 years that it was in production, but the casting # was always 9-1, 942, 948 or 954.

Although the Atlas numbering system does not prohibit suffix letters on casting numbers (see the <physically look at> later 10" and 3/8" bed 12" headstock castings for examples), more finish-machined parts have suffix letters than do castings. The 10" and 12" bed castngs up until 1957 were always 9-1, 942, 948 or 954.
 
Back
Top