Union Machine Works was a machining company in Jack London Square that had been "Machining since 1885". The building fills part of the block on Clay Street between 2nd and 3rd Streets.
It's unclear when the current building was constructed, but a 1905 classified says Union Machine Works was at 3rd and Franklin and a 1921 copy of California Shipbuilder and Metalworker lists the address as 367 - 3rd Street which is near Franklin, and lists them under both 'Steel Ship Repairers' and 'Machinists—Jobbing'. 1
The 1935 directory lists them at 369 - 3rd Street, and William Musladin as president and J. J. Knight as secretary-treasurer. c.1948, Henry Charles Wieking worked there as a machinist.
Unknown when it closed, but a SeeClickFix report from 2013 said it was vacant then.
Links and References
- California Shipbuilder and Metalworker Volume 2, March 1921