The Z axis go down after "Z home" in CNC mode.
Dear Experts!
My 3D printer is CNC mode now.
When I send "Z home" command, the motor sit down until Z min, after go down approx 40 mm (of course it can't).
If I push the Z min switch earlier, then the Z axis stop, go up and down 5mm (it's OK), but after go down 40mm again.
If Z probe is dissabled then the Z axis works properly.
This is the Z probe code:
My 3D printer is CNC mode now.
When I send "Z home" command, the motor sit down until Z min, after go down approx 40 mm (of course it can't).
If I push the Z min switch earlier, then the Z axis stop, go up and down 5mm (it's OK), but after go down 40mm again.
If Z probe is dissabled then the Z axis works properly.
This is the Z probe code:
#define Z_PROBE_Z_OFFSET 0
#define Z_PROBE_Z_OFFSET_MODE 0
#define UI_BED_COATING 1
#define FEATURE_Z_PROBE 1
#define EXTRUDER_IS_Z_PROBE 0
#define Z_PROBE_DISABLE_HEATERS 0
#define Z_PROBE_BED_DISTANCE 30
#define Z_PROBE_PIN ORIG_Z_MIN_PIN
#define Z_PROBE_PULLUP 0
#define Z_PROBE_ON_HIGH 0
#define Z_PROBE_X_OFFSET 0
#define Z_PROBE_Y_OFFSET 0
#define Z_PROBE_WAIT_BEFORE_TEST 1
#define Z_PROBE_SPEED 2
#define Z_PROBE_XY_SPEED 150
#define Z_PROBE_SWITCHING_DISTANCE 1
#define Z_PROBE_REPETITIONS 1
#define Z_PROBE_USE_MEDIAN 0
#define Z_PROBE_HEIGHT -20
#define Z_PROBE_DELAY 0
#define Z_PROBE_START_SCRIPT ""
#define Z_PROBE_FINISHED_SCRIPT ""
#define Z_PROBE_RUN_AFTER_EVERY_PROBE ""
#define Z_PROBE_REQUIRES_HEATING 0
#define Z_PROBE_MIN_TEMPERATURE 150
#define FEATURE_AUTOLEVEL 0
#define FEATURE_SOFTWARE_LEVELING 0
#define Z_PROBE_X1 20
#define Z_PROBE_Y1 20
#define Z_PROBE_X2 160
#define Z_PROBE_Y2 20
#define Z_PROBE_X3 20
#define Z_PROBE_Y3 160
#define BED_LEVELING_METHOD 0
#define BED_CORRECTION_METHOD 0
#define BED_LEVELING_GRID_SIZE 5
Comments
does not sound good. -20 means it triggers when you rammed the nozzle 20mm into bed. With cnc it is different normally. Does this also measure length of tool so z=0 is the tip of the mill?
I have a special switch for my cnc so it triggers x mm before (height of sensor). In my case nearly 40mm.
Problem is that firmware knows that bed is 40mm deeper. So actually I do not home z axis but I use G30 to home Z axis.
The second variant is what you need to define levels for homing replacement.
Can I upload an image?
This is my idea:
https://drive.google.com/file/d/1zyfqD0u7M9DCGs1s37enWivfk_vqJHI4/view?usp=sharing
Is this correct?
Now it depends a bit how your cnc code looks like. Do you need z=0 at wood top or bottom. This command is a combination of setting real bottom and Z offset as done with G92. So lets say wood has 30mm and you want wood top to be z=0 but allow moving down to z=-30 so you can reach the bottom. If I get it right (please test first with test triggering in free air) you would send:
G30 H50 R20
when z probe height is 0. When z probe height is -20 as in your settings it reduces to less math:
G30 H30 R0
If you want the wood bottom to be 0 it would be
G30 H30 R30
So H is always the height you measured and R is which Z position you want to assign it.
The printer are CNC mode....
Why?
The motor strains, but not place... :-(
Where can I the z max homing switch?