fine boring cycle
The G76 code word is used to bore downward under feed, stop the spindle, orient the tool, jog away from the bored surface, and then rapid back to the initail plane. This bores in one direction only and rapids out without leaving a witness mark as would happen with G86. The Q word sets the jog distance. (note that the spindle stop and orient is the same as M19)
The following example is animated below:
G76 X0Y0Z-2.125 R-.875 F10 Q.25 G98