Samasaleh, most of us are not into industrial or leather machines. As mentioned in this thread, the "W" serial number is not like many of the other Singer serial numbers.
I'm thinking that leather working forums might better be able to help. Another resource to identify older Singer machines, would be the Smithsonian particularly
https://www.sil.si.edu/DigitalCollec...2752/index.htm and
https://www.sil.si.edu/DigitalCollec...0144/index.htm
Janey - Neat people never make the exciting discoveries I do.
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