Recently purchase a IS-400 and would like to know how much tension to set the Spindle Spring using the Pressure Knurl. I'm going to be engraving gun steel not plastic if that makes any difference.The owners manual shows the knurl in the diagram on page 13 and mentions it on page 37 under "Setting up the Spindle" "Unscrew the pressure knurl on spindle (2) until you can see the second mark.) What second Mark? and How Much Tension to Re-Apply after setting the dial?
Any help would be greatly appreciated.
Thanks