CNC Services Northwest

Method 2: Use an imaginary reference tool

Use this method if you have several tools you wish to set up, keep, and reuse; and you have a consistent tool measuring surface (e.g. the table of a bed mill).



Preparation (one-time)

  1. Go to the offset library: F1/Setup -> F2/Tool -> F1/Offsets
  2. Press TOOL CHECK to send the Z axis to Z home.
  3. Press F1 to set Z Reference.
  4. Press F10 to set Z Reference at Z Home.

Operation (for each job)

  1. Load all of the tools for the job into their tool holders.
  2. Go to the offset library: F1/Setup -> F2/Tool -> F1/Offsets
  3. For each tool in the job:
    1. Highlight the tool/offset number.
    2. Load the tool.
    3. Jog to touch off on the standard measuring surface.
    4. Press F2 to measure the offset.
  4. Press F10 to save the measured offsets.
  5. Go to Part Setup: F1/Setup -> F1/Part
  6. Touch off and set X and Y positions normally.
  7. Touch off the part surface with whatever tool happens to be in the spindle.
  8. Enter the correct Tool Number, then press F10 to set the Z position.

If you have to replace one tool

  1. Go to the Offset Library
  2. Load and measure the new tool off the same surface you always use.


For a permanent measuring surface you might choose the surface of the table (if it is not likely to be covered by a large fixture), the fixed jaw of a vise (if the vise always stays on the table); or any other permanently-mounted fixture.

A variation on this method is to measure every tool for every job, off any convenient surface. In this case you do not maintain any tool measurements from one job to the next, and you can use the stock surface, a temporary fixture, or any other convenient surface to measure the tools.

Note that it is not necessary to set the Z axis part zero before you measure tools, nor is it necessary that you measure your tools using the stock surface. You just need to set the Z axis part zero using the stock surface after you have measured the tools on the usual measuring surface.

Copyright © 2017 Marc Leonard
Last updated 15-May-2017 MBL