Pictures Of the Factories

[Chickenthief]

Originally Posted by Puretexan

I wonder what kind of machine they used to cut the rectangular hole for the safety bar.
Its already thin and they cut a perfect hole for it to ride in. I can't imagine how they did it. I have a mill and doubt that I could do it.

A round pilot hole drilled and a square reamer pushed through.
https://www.youtube.com/watch?v=7n1r5XfVkyk

Way back then they had umpteen machines in a long row each only doing one operation.