Gang, have a look at this picture.. I know I've seen this type
of pattern before and I'm finding everywhere on the hexes (and
nuts/bolts) of my colchester student:
I assume these are some sort of marks left by an "auto feed" lathe / machine ..
but would they have been using auto (stock) feed in '65?
PS the pic is of a ~1/2" hex its the stud that keeps the belt guard on the
machine but like i said I'm finding those series circles (of diff sizes) every
where as I clean this machine up.