To hold the centerline on the workpiece will help the device shown in the figure.
Recommend to read
THE TRUCK WAS A TRACTOR
I'm a longtime, or rather, hereditary subscriber of the journal "modelist-Konstruktor". First (1972) the journal was written by my father - Galkin Grigory Petrovich (he is now 80 years...
Three-wheeled “Combi”
The family of tricycles has been joined by another interesting machine — the "combi", which was invariably popular with visitors to the NTTM-76 exhibition. It was created at the Kharkiv...