Service Home How To Procedures Mill - Thermal Growth - Test Procedure - AD0815
Last updated: 02/20/2025

Mill - Thermal Growth - Test Procedure

AD0815

Mill - Thermal Growth - Checklist

This test procedure will cover how to run the thermal growth test to help diagnose inaccuracy on Haas Mills. To start, download the checklist below and fill it out. Review the results with your HFO and contact Haas Applications if necessary. 

Mill Thermal Growth Checklist

This video demonstrates how to set up and run the thermal growth test on your Haas Mill.

Note: This service video is for reference only and does not replace the written procedure.

Mill - Thermal Growth - Test Procedure - Setup

Test Program Description:

This test is a standardized cutting program in which the machine will air cut and probe on a vise corner to see changes in probing from thermal growth.

Machine Requirements:

  • Mill NGC Machine
  • WIPS 
  • A vise 
Inch Test Program:

Metric Test Program:

Tools:

  • Tool #1: OMP40-2
  • Tool #2: a tool holder that will spin up to max RPM

Calibrate Tools:

  • Measure the tool offset for the probe as tool #1.
    •  Refer to WIPS - Installation - AD0222  to check the run out on the OMP40-2 and recalibrate the probe before measuring the tool offset.        
  • Measure the tool offset for tool #2

Position of vise:

  • Position the vise near the center of the table/platter

Mill - Thermal Growth - Test Procedure - Work Offsets

G54:

Set G54 on front left corner of vise to have reference for probe measurements.

  • G54 X set on left side of vise [1].
  • G54 Y set on front side of vise [2].
  • G54 Z set on top of vise [3].

G55:

Set G55 to middle of table for air cutting.

  • G55 X set close to the center of X travel.
  • G55 Y set close to the center of Y travel.
  • G55 Z set close to the center of Z travel.

Note: The Z axis offset does not need to be exact and can be adjusted toward the table after running the program to see where the Z axis is starting.

Mill - Thermal Growth - Test Procedure - Run Test Program

Test Program:

The machine will simulate cutting a part high above the table. This will be done with tool two and will simulate contouring, pocketing, drilling and tapping. The machine will then change to tool 1 and come down and check the thermal growth by touching off on the front left corner that was set for G54. The test will then reset to the beginning and repeat until the feed hold and reset button is pushed.

 Note: Make sure the machine is cold and has not warmed up at all, besides by setting the work and tool offsets. 

Run the test program:

Note: Run the program from Memory and not the USB.

Run this program for a minimum of three hours. Record the ambient temperature near the machine every hour while the test is running. 

A DPRINT file will be saved to the User Data folder. Take an error report at this time. Attach the Error Report, DPRINT File, and ambient temperature recordings to a work order for the machine and contact Haas Service.

 Note: If the tool length offset changes by more than .002” between probe hits, you will get a #3000 alarm, to fix this simply restart the program.