A friend recently found a Starrett vernier caliper, 5 in., which is marked in thousands on one side and the back side is in 64ths. The 1934 Starrett catalog shows a 5 inch vernier caliper but does not list it as available. They start with 6 inch and go up to 48 inch with longer sizes available on special order. When did machinists start using thousandths and leave fractions of an inch.
I remember in the 1960s hearing a Boeing machinist complaining that Boeing was requiring them to work with ten thousandths with lathes made in the early 40s calibrated in thousandths.
Can anyone help?
