Weird Auto Bed Level - Y Axis

Guys,

I need some help.

I managed to setup Auto level with a Servo. Everything seem to be good and it was working.

Some issue with homing where it doesn't raise high enough for the probe and eventually broke it.

I repair the probe and did a new calculation

1. Move the Extruder to a dot
2. G92 X0 Y0 Z0
3. Raise the Extruder and lower the probe using M280 P0 S0
4. Do the normal and the use M119 to get the info
5. Put those information back into Marlin and upload the new firmware.

After I have done that

1. I still have issue with homing. It doesn't raise the extruder if I issue G28 or press the homing button in the Repetier

2. I am at the G28 position(home). I issue a G29.

It start to detect the bed information

Point 1 : It probe the Home location

ISSUE happen here - Point 2 : it is suppose to move the Y - Axis. But it is not. it probe the same point as point 1

Point 3: it will move to the right and probe X=168 but Y=0

Once the probe it done, in the repetier, the Y somehow become Y=165

Please help.

If I do not do G28. Assuming I issue the G29 comment at the last spot above, then it will move to the correct probe location

18:32:18.969 : Bed x: 30 y: 165 z: 8.31
18:32:27.090 : Bed x: 30 y: 30 z: 8.30
18:32:37.592 : Bed x: 165 y: 30 z: 7.28
18:32:37.597 : echo:endstops hit: X:0.00 Y:165.00 Z:7.28
18:35:42.038 : Bed x: 30 y: 165 z: 7.34
18:35:51.951 : Bed x: 30 y: 30 z: 8.07
18:36:02.449 : Bed x: 165 y: 30 z: 7.06
18:36:02.457 : echo:endstops hit: X:-2.93 Y:30.15 Z:7.06


*******************************************************************************************************************************************************

#define ENABLE_AUTO_BED_LEVELING // Delete the comment to enable (remove // at the start of the line)

#ifdef ENABLE_AUTO_BED_LEVELING

// these are the positions on the bed to do the probing
#define LEFT_PROBE_BED_POSITION 30
#define RIGHT_PROBE_BED_POSITION 165
#define BACK_PROBE_BED_POSITION 165
#define FRONT_PROBE_BED_POSITION 30

// these are the offsets to the prob relative to the extruder tip (Hotend - Probe)
#define X_PROBE_OFFSET_FROM_EXTRUDER 33
#define Y_PROBE_OFFSET_FROM_EXTRUDER -0
#define Z_PROBE_OFFSET_FROM_EXTRUDER -8.39

#define Z_RAISE_BEFORE_HOMING 10 // (in mm) Raise Z before homing (G28) for Probe Clearance.
// Be sure you have this distance over your Z_MAX_POS in case

#define XY_TRAVEL_SPEED 4000 // X and Y axis travel speed between probes, in mm/min

#define Z_RAISE_BEFORE_PROBING 15 //How much the extruder will be raised before traveling to the first probing point.
#define Z_RAISE_BETWEEN_PROBINGS 10 //How much the extruder will be raised when traveling from between next probing points


//If defined, the Probe servo will be turned on only during movement and then turned off to avoid jerk
//The value is the delay to turn the servo off after powered on - depends on the servo speed; 300ms is good value, but you can try lower it.
// You MUST HAVE the SERVO_ENDSTOPS defined to use here a value higher than zero otherwise your code will not compile.

// #define PROBE_SERVO_DEACTIVATION_DELAY 300

#endif

//
#define NUM_SERVOS 1 // Servo index starts with 0 for M280 command

// Servo Endstops
//
// This allows for servo actuated endstops, primary usage is for the Z Axis to eliminate calibration or bed height changes.
// Use M206 command to correct for switch height offset to actual nozzle height. Store that setting with M500.
//
#define SERVO_ENDSTOPS {-1, -1, 0} // Servo index for X, Y, Z. Disable with -1
#define SERVO_ENDSTOP_ANGLES {0,0, 0,0, 3,70} // X,Y,Z Axis Extend and Retract angles

Is your home at the front left or back right? Also your probe offset is bigger than your grid size by 3 mm which I know has caused other people problems. Not sure if it makes a difference but maybe remove the - before 0 in y offset. Not sure if it treats 0 and -0 the same.

All,

I found the problem.

X_PROBE_OFFSET_FROM_EXTRUDER < LEFT_PROBE_BED_POSITION

If you do like mine below, it will cause a -X value in the G29 code.

Hope this help.

#define LEFT_PROBE_BED_POSITION 30
#define RIGHT_PROBE_BED_POSITION 165
#define BACK_PROBE_BED_POSITION 165
#define FRONT_PROBE_BED_POSITION 30

// these are the offsets to the prob relative to the extruder tip (Hotend - Probe)
#define X_PROBE_OFFSET_FROM_EXTRUDER 33
#define Y_PROBE_OFFSET_FROM_EXTRUDER -0
#define Z_PROBE_OFFSET_FROM_EXTRUDER -8.39

So exactly what I said then.