The G38.6 command is used for digitising parts using a touch probe or similar device. It is typically used to create a point cloud capture of a three-dimensional object or to map uneven material surfaces for engraving applications when used with auto-levelling software.

When a G38.6 command is executed, the specified axis will move until the probe input is triggered.

When a probe touch is detected, the X, Y, and Z working coordinates of the touch point are recorded in a file named "MASSO Probe data.txt".

If the "MASSO Probe data.txt" file does not exist, MASSO will automatically create a new file. If the file already exists, the new probe data will be appended to the end of the existing file.

If the probe does not trigger before reaching the specified position, a “Probing error at:” entry is written to the "MASSO Probe data.txt" file, the program will stop, and a Probing Error alarm will be displayed on the screen.

All coordinates used with the G38.6 command are working coordinates, and all recorded values written to the "MASSO Probe data.txt" file are also working coordinates.

To use the G38.6 command, a probe input must be assigned. The probe input must change state from Low to High when the probe is triggered.

Syntax & Parameters

The X, Y, or Z value specifies the axis to be used for probing and the working coordinate position to move towards.

The F value defines the feed rate at which the probing movement will occur.

Example Program

N10 G1 X20 Y10 F1000
N20 G38.6 Z-3 F100
N30 G0 Z2

In this example, the machine first moves to X20 Y10.

The Z axis then probes down towards the working coordinate Z-3. If the probe detects a touch before reaching this position, the motion stops and the X, Y, and Z working coordinates are recorded in the "MASSO Probe data.txt" file.

If the probe does not trigger before reaching Z-3, the machine stops and records the following entry in the data file:

Probing error at: 20.00000, 10.00000

Sample Data File

0.00000, 0.00000, -0.88750

0.13310, 0.00000, -0.90749

0.26619, 0.00000, -0.91750

0.38597, 0.00000, -0.92249

Probing error at: 0.00000, -0.92000

Sample Digitized Item