What Are Tool and Work Offsets
Channel: CNCQuickGuide
Date: 2018-09-01

https://www.cncquickguide.com/
What are offsets in a machine tool ?  In the most basic sense the offsets are what the machine tool controller “knows” about the tools and the workpiece.  In a technical sense the offsets are numbers stored in specific registers in the memory of the controller.  The typical program run on a CNC machine tool contains a series of commands related to starting and stopping the spindle and moving the tip or the edge of a cutting tool through a series of points.

Offsets are what lets the programmer write a program without setting up the machine tool first, in some cases without even knowing what machine tool will be used.  Every machine tool will have a machine coordinate system.  This is typically a Cartesian system with the z axis aligned with the spindle and x and y axes perpendicular to the z axis and each other.   (In a 2 axis lathe the z axis is still aligned with the spindle and the y axis is omitted.)  When a machine tool is in its “home” position all of the axes are typically positioned at one extreme of travel (see Machine Tool Motion.)