Need help with GCODE for tool changer probe

[3DStyle]

I saw the BitSetter by Carbide 3D and wanted to implement it into the RS-CNC.



I have a momentary button switch and I 3D printed a holder for it.
I am able to do probes with it, but I'm stuck with writing a GCODE for making it to work properly.

I will appreciate if someone can help me to write a GCODE that will do the following:
1. Stop the job for changing to new tool.
2. Home Z axis to change tool.
3. Go to a fixed XY location where the Z probe is at.
4. Initialise Z probing cycle.
- Until here I feel confident with my GCODE script I wrote, but from now on I'm lost -
5. Calculate and compensate the new tool height and go back to the right Z highest where the workpiece is at - this is where I'm stuck.

[Steve H]

I appretiate this isnt quite the same but have you taken a look at the instructions on the CNC32 for implementing a z probe. This may help you get started at least.
https://www.makerfr.com/en/cnc/grbl-32- ... oi-du-tft/

G91 G21 ; (Relative position in mm.)
G38.2 Z-30 F100 ;(Search of the probe on 30 mm. speed 100, if not found after 30 mm. Alarm GRBL)
G0 Z1 ; (back 1mm.)
G38.2 Z-1 F10 ; (Searching the probe for 1 mm, slower, speed 10)
G92 Z20 ; (Adjustment of the Z offset according to the thickness of the probe, 20 mm in this case)
G0 Z3 ; (back 3mm.)

[3DStyle]

I tried to get some help from this GCODE but the problem is that the BitSetter, as you said, is not the same.
The Z probe that you refered to is working with a known height of the Z plate. With a BitSetter, the machine needs to know the tool Z offset from two tools that have been changed. I'm not sure how to do that.

[RoMaker]

Hi,
I don't know how the machine can gess the height of your material to mill with your system if the probe is on the side of the machine ..! the probe must be on the piece to mill.
Each job is different, the lenght of the endmill, the height of the material to mill... Maybe i'm dumb, but i really don't see how to do with your system of probe.

[3DStyle]

Please refer to the BitSetter product page from Carbide 3D.

The BitSetter is an automatic tool offset probe. The BitSetter measures the length of the cutter in your spindle and, combined with Carbide Motion, automatically resets your Z-axis zero point to reflect the new length, making tool changes simple and straight forward.

From my understanding, this works by first probing Z axis using the BitSetter with the first tool of your milling job.
Then, you zero the Z axis height to your workpiece. When you change the endmill to a different one (M6 command), the machine
will probe the Z axis using the BitSetter again to measure the new tool and will calculate the differences in length from the previous tool that was used.
Finally the machine will go back to the workpiece and will know the correct Z axis height of the workpiece in order to continue the milling job.

You can see how it works in this video.