I've been doing a little digging on the Pacific Iron and Machine Co. of San Diego.
Owned by Robert R Jones and Estal Render Bourne, the company first appeared in the San Diego City Directory in 1950, located at 3105 Hancock (the building still exists). The 1952 Directory notes that the company is "machy mfrs" while the 1953-54 Directory states they are "steel fabricators."
Tracing each owner backwards, Jones, in 1942, was manager of the Motor Hardware & Equipment Company while Bourne was an aircraft worker for CACorp. in the 1944-45 Directory, both men are listed as owners of the Pacific Tool & Die Company located at 917 University Ave - R.R. Potter was the 3rd owner.
Estal Bourne is credited with patent (#1,707,456, dated April 2, 1929, originally filed May 20, 1926. for a 'Pipe Threading Means" You can search for this on the Google Patents website.
I'll add more to this post as i find it.