Add SKEW_CORRECTION to example configs

Marlin/example_configurations/AlephObjects/TAZ4/Configuration.h

@@ -852,7 +852,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1064,6 +1064,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (8*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/AliExpress/CL-260/Configuration.h

@@ -832,7 +832,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1044,6 +1044,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Anet/A6/Configuration.h

@@ -951,7 +951,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1201,6 +1201,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Anet/A8/Configuration.h

@@ -839,7 +839,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1051,6 +1051,63 @@
 #define HOMING_FEEDRATE_XY (100*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/BQ/Hephestos/Configuration.h

@@ -823,7 +823,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1035,6 +1035,63 @@
 #define HOMING_FEEDRATE_XY 2000
 #define HOMING_FEEDRATE_Z  150
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/BQ/Hephestos_2/Configuration.h

@@ -833,7 +833,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1045,6 +1045,63 @@
 #define HOMING_FEEDRATE_XY (60*60)
 #define HOMING_FEEDRATE_Z  120
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/BQ/WITBOX/Configuration.h

@@ -823,7 +823,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1035,6 +1035,63 @@
 #define HOMING_FEEDRATE_XY (120*60)
 #define HOMING_FEEDRATE_Z  432
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Cartesio/Configuration.h

@@ -831,7 +831,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1043,6 +1043,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (10*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Creality/CR-10/Configuration.h

@@ -842,7 +842,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1054,6 +1054,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Felix/Configuration.h

@@ -814,7 +814,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1026,6 +1026,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Felix/DUAL/Configuration.h

@@ -814,7 +814,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1026,6 +1026,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/FolgerTech/i3-2020/Configuration.h

@@ -835,7 +835,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1049,6 +1049,63 @@
 #define HOMING_FEEDRATE_XY (40*60)
 #define HOMING_FEEDRATE_Z  (55)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Geeetech/GT2560/Configuration.h

@@ -847,7 +847,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1059,6 +1059,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Geeetech/I3_Pro_X-GT2560/Configuration.h

@@ -832,7 +832,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1044,6 +1044,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Infitary/i3-M508/Configuration.h

@@ -836,7 +836,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1048,6 +1048,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Malyan/M150/Configuration.h

@@ -856,7 +856,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1072,6 +1072,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Micromake/C1/basic/Configuration.h

@@ -836,7 +836,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1048,6 +1048,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Micromake/C1/enhanced/Configuration.h

@@ -836,7 +836,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1048,6 +1048,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/RepRapWorld/Megatronics/Configuration.h

@@ -832,7 +832,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1044,6 +1044,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/RigidBot/Configuration.h

@@ -830,7 +830,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1042,6 +1042,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (15*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/SCARA/Configuration.h

@@ -844,7 +844,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1056,6 +1056,63 @@
 #define HOMING_FEEDRATE_XY (40*60)
 #define HOMING_FEEDRATE_Z  (10*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Sanguinololu/Configuration.h

@@ -863,7 +863,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1075,6 +1075,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (6*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/TinyBoy2/Configuration.h

@@ -888,7 +888,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1100,6 +1100,63 @@
 #define HOMING_FEEDRATE_XY (40*60)
 #define HOMING_FEEDRATE_Z  (3*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Velleman/K8200/Configuration.h

@@ -862,7 +862,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1074,6 +1074,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Velleman/K8400/Configuration.h

@@ -832,7 +832,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1044,6 +1044,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (8*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/Velleman/K8400/Dual-head/Configuration.h

@@ -832,7 +832,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1044,6 +1044,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (8*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/adafruit/ST7565/Configuration.h

@@ -832,7 +832,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1044,6 +1044,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/delta/FLSUN/auto_calibrate/Configuration.h

@@ -962,7 +962,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1177,6 +1177,63 @@
 // Delta only homes to Z
 #define HOMING_FEEDRATE_Z  (100*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/delta/FLSUN/kossel_mini/Configuration.h

@@ -962,7 +962,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1171,6 +1171,63 @@
 // Delta only homes to Z
 #define HOMING_FEEDRATE_Z  (45*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/delta/generic/Configuration.h

@@ -949,7 +949,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1166,6 +1166,63 @@
 // Delta only homes to Z
 #define HOMING_FEEDRATE_Z  (200*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/delta/kossel_mini/Configuration.h

@@ -952,7 +952,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1169,6 +1169,63 @@
 // Delta only homes to Z
 #define HOMING_FEEDRATE_Z  (200*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/delta/kossel_pro/Configuration.h

@@ -952,7 +952,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1169,6 +1169,63 @@
 // Delta only homes to Z
 #define HOMING_FEEDRATE_Z  (200*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/delta/kossel_xl/Configuration.h

@@ -961,7 +961,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1178,6 +1178,63 @@
 // Delta only homes to Z
 #define HOMING_FEEDRATE_Z  (60*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/gCreate/gMax1.5+/Configuration.h

@@ -846,7 +846,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1058,6 +1058,63 @@
 #define HOMING_FEEDRATE_XY (60*60)
 #define HOMING_FEEDRATE_Z  (14*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/makibox/Configuration.h

@@ -835,7 +835,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1047,6 +1047,63 @@
 #define HOMING_FEEDRATE_XY 1500
 #define HOMING_FEEDRATE_Z  (2*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/tvrrug/Round2/Configuration.h

@@ -827,7 +827,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1039,6 +1039,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================

Marlin/example_configurations/wt150/Configuration.h

@@ -837,7 +837,7 @@
 //===========================================================================
 //=============================== Bed Leveling ==============================
 //===========================================================================
-// @section bedlevel
+// @section calibrate
 
 /**
  * Choose one of the options below to enable G29 Bed Leveling. The parameters
@@ -1049,6 +1049,63 @@
 #define HOMING_FEEDRATE_XY (50*60)
 #define HOMING_FEEDRATE_Z  (4*60)
 
+// @section calibrate
+
+/**
+ * Bed Skew Compensation
+ *
+ * This feature corrects for misalignment in the XYZ axes.
+ *
+ * Take the following steps to get the bed skew in the XY plane:
+ *  1. Print a test square (e.g., https://www.thingiverse.com/thing:2563185)
+ *  2. For XY_DIAG_AC measure the diagonal A to C
+ *  3. For XY_DIAG_BD measure the diagonal B to D
+ *  4. For XY_SIDE_AD measure the edge A to D
+ *
+ * Marlin automatically computes skew factors from these measurements.
+ * Skew factors may also be computed and set manually:
+ *
+ *  - Compute AB     : SQRT(2*AC*AC+2*BD*BD-4*AD*AD)/2
+ *  - XY_SKEW_FACTOR : TAN(PI/2-ACOS((AC*AC-AB*AB-AD*AD)/(2*AB*AD)))
+ *
+ * If desired, follow the same procedure for XZ and YZ.
+ * Use these diagrams for reference:
+ *
+ *    Y                     Z                     Z
+ *    ^     B-------C       ^     B-------C       ^     B-------C
+ *    |    /       /        |    /       /        |    /       /
+ *    |   /       /         |   /       /         |   /       /
+ *    |  A-------D          |  A-------D          |  A-------D
+ *    +-------------->X     +-------------->X     +-------------->Y
+ *     XY_SKEW_FACTOR        XZ_SKEW_FACTOR        YZ_SKEW_FACTOR
+ */
+//#define SKEW_CORRECTION
+
+#if ENABLED(SKEW_CORRECTION)
+  // Input all length measurements here:
+  #define XY_DIAG_AC 282.8427124746
+  #define XY_DIAG_BD 282.8427124746
+  #define XY_SIDE_AD 200
+
+  // Or, set the default skew factors directly here
+  // to override the above measurements:
+  #define XY_SKEW_FACTOR 0.0
+
+  //#define SKEW_CORRECTION_FOR_Z
+  #if ENABLED(SKEW_CORRECTION_FOR_Z)
+    #define XZ_DIAG_AC 282.8427124746
+    #define XZ_DIAG_BD 282.8427124746
+    #define YZ_DIAG_AC 282.8427124746
+    #define YZ_DIAG_BD 282.8427124746
+    #define YZ_SIDE_AD 200
+    #define XZ_SKEW_FACTOR 0.0
+    #define YZ_SKEW_FACTOR 0.0
+  #endif
+
+  // Enable this option for M852 to set skew at runtime
+  //#define SKEW_CORRECTION_GCODE
+#endif
+
 //=============================================================================
 //============================= Additional Features ===========================
 //=============================================================================