diff --git a/Marlin/Configuration_adv.h b/Marlin/Configuration_adv.h
index 9a378f589a085894532aaf7f46c7f8c20df5f79e..247b6727229a2bd19574a58945a5856c3b7972a5 100644
--- a/Marlin/Configuration_adv.h
+++ b/Marlin/Configuration_adv.h
@@ -592,6 +592,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index b7b4473c9626fdd180bd9e7d96edae3d9b4d3d26..3c6a5c02a6c1596b81c01e2c76f727f49abce6bd 100755
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -7601,7 +7601,24 @@ inline void gcode_M503() {
*/
inline void gcode_M905() {
stepper.synchronize();
- planner.advance_M905(code_seen('K') ? code_value_float() : -1.0);
+
+ const float newK = code_seen('K') ? code_value_float() : -1,
+ newD = code_seen('D') ? code_value_float() : -1,
+ newW = code_seen('W') ? code_value_float() : -1,
+ newH = code_seen('H') ? code_value_float() : -1;
+
+ if (newK >= 0.0) planner.set_extruder_advance_k(newK);
+
+ SERIAL_ECHO_START;
+ SERIAL_ECHOLNPAIR("Advance factor: ", planner.get_extruder_advance_k());
+
+ if (newD >= 0 || newW >= 0 || newH >= 0) {
+ const float ratio = (!newD || !newW || !newH) ? 0 : (newW * newH) / (sq(newD * 0.5) * M_PI);
+ planner.set_advance_ed_ratio(ratio);
+ SERIAL_ECHO_START;
+ SERIAL_ECHOPGM("E/D ratio: ");
+ if (ratio) SERIAL_ECHOLN(ratio); else SERIAL_ECHOLNPGM("Automatic");
+ }
}
#endif
diff --git a/Marlin/example_configurations/Cartesio/Configuration_adv.h b/Marlin/example_configurations/Cartesio/Configuration_adv.h
index e629b7f48c7e277395d56851a8bbb0de9f001fc9..5280af8cd128730081fab1b5af84301962932fbd 100644
--- a/Marlin/example_configurations/Cartesio/Configuration_adv.h
+++ b/Marlin/example_configurations/Cartesio/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/Felix/Configuration_adv.h b/Marlin/example_configurations/Felix/Configuration_adv.h
index 010d2c018d810dc493128b9ac1564a3a9aa51dce..2ebb2f5e4eee781ba038d95af2a148591f95cf0f 100644
--- a/Marlin/example_configurations/Felix/Configuration_adv.h
+++ b/Marlin/example_configurations/Felix/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/Hephestos/Configuration_adv.h b/Marlin/example_configurations/Hephestos/Configuration_adv.h
index 1877ace1bc6b99d4f238252fe2ed62337f544244..65af0e844c33f0adf5552a9ebb4c22da86909028 100644
--- a/Marlin/example_configurations/Hephestos/Configuration_adv.h
+++ b/Marlin/example_configurations/Hephestos/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/Hephestos_2/Configuration_adv.h b/Marlin/example_configurations/Hephestos_2/Configuration_adv.h
index d26300e0e75dab927451a52ed2774321c9a27755..d4adbb60e6dfe82b7a2f5c822b4ee4b866403b20 100644
--- a/Marlin/example_configurations/Hephestos_2/Configuration_adv.h
+++ b/Marlin/example_configurations/Hephestos_2/Configuration_adv.h
@@ -572,6 +572,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/K8200/Configuration_adv.h b/Marlin/example_configurations/K8200/Configuration_adv.h
index aa4db9c689810752b13d283976d3a5ee6cfc678f..fbd4aeff4dd39f134afac1ec217d98af7ee3061e 100644
--- a/Marlin/example_configurations/K8200/Configuration_adv.h
+++ b/Marlin/example_configurations/K8200/Configuration_adv.h
@@ -602,6 +602,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 140 // start value for PLA on K8200
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/K8400/Configuration_adv.h b/Marlin/example_configurations/K8400/Configuration_adv.h
index bb2e1e49e5a87835dce686ec55140db74da928ac..992bab4251b3a2f711394779c99e12b26170f52a 100644
--- a/Marlin/example_configurations/K8400/Configuration_adv.h
+++ b/Marlin/example_configurations/K8400/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/RigidBot/Configuration_adv.h b/Marlin/example_configurations/RigidBot/Configuration_adv.h
index f8eef6f569f9c099227ed9c501eee4cd129a4924..f8f2f0b4c293b1b6fb25e0b11ff810cffd124667 100644
--- a/Marlin/example_configurations/RigidBot/Configuration_adv.h
+++ b/Marlin/example_configurations/RigidBot/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/SCARA/Configuration_adv.h b/Marlin/example_configurations/SCARA/Configuration_adv.h
index 892d2edebc61d85d780e3ada250212e39fa3dfec..63eaedfb4d2c0e000d822c4a900817ad1b3d7b46 100644
--- a/Marlin/example_configurations/SCARA/Configuration_adv.h
+++ b/Marlin/example_configurations/SCARA/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/TAZ4/Configuration_adv.h b/Marlin/example_configurations/TAZ4/Configuration_adv.h
index 86d2737535bad112b3a875c0767a3706e80c876c..d0c2b481b0a2aea0b37f2c85d9ca4ce0abaae142 100644
--- a/Marlin/example_configurations/TAZ4/Configuration_adv.h
+++ b/Marlin/example_configurations/TAZ4/Configuration_adv.h
@@ -597,6 +597,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/WITBOX/Configuration_adv.h b/Marlin/example_configurations/WITBOX/Configuration_adv.h
index 1877ace1bc6b99d4f238252fe2ed62337f544244..65af0e844c33f0adf5552a9ebb4c22da86909028 100644
--- a/Marlin/example_configurations/WITBOX/Configuration_adv.h
+++ b/Marlin/example_configurations/WITBOX/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/delta/generic/Configuration_adv.h b/Marlin/example_configurations/delta/generic/Configuration_adv.h
index 5d75ba3cf504bd6e82dffcd22ffaff37eb914ba5..a2236a9c80e886e41e5cbb27e86f8431c5019e72 100644
--- a/Marlin/example_configurations/delta/generic/Configuration_adv.h
+++ b/Marlin/example_configurations/delta/generic/Configuration_adv.h
@@ -591,6 +591,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/delta/kossel_mini/Configuration_adv.h b/Marlin/example_configurations/delta/kossel_mini/Configuration_adv.h
index 5d75ba3cf504bd6e82dffcd22ffaff37eb914ba5..a2236a9c80e886e41e5cbb27e86f8431c5019e72 100644
--- a/Marlin/example_configurations/delta/kossel_mini/Configuration_adv.h
+++ b/Marlin/example_configurations/delta/kossel_mini/Configuration_adv.h
@@ -591,6 +591,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/delta/kossel_pro/Configuration_adv.h b/Marlin/example_configurations/delta/kossel_pro/Configuration_adv.h
index 9f3a9f3d2f76484cdb14f454f454701e847fcbec..cc39740a3cf9f5c9b2d3ba1939c1654684e82906 100644
--- a/Marlin/example_configurations/delta/kossel_pro/Configuration_adv.h
+++ b/Marlin/example_configurations/delta/kossel_pro/Configuration_adv.h
@@ -596,6 +596,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/delta/kossel_xl/Configuration_adv.h b/Marlin/example_configurations/delta/kossel_xl/Configuration_adv.h
index 78a52f8323fca0af221b1391e28c389451ebb62a..814bcc464af2bb6888e5003256f5a7149b262c0f 100644
--- a/Marlin/example_configurations/delta/kossel_xl/Configuration_adv.h
+++ b/Marlin/example_configurations/delta/kossel_xl/Configuration_adv.h
@@ -591,6 +591,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/makibox/Configuration_adv.h b/Marlin/example_configurations/makibox/Configuration_adv.h
index 87de6007b3b44bd6e2184d8aedc7f034d1468f05..9d06015a8bb12ae5daa525317f36ed7b4b1eceaf 100644
--- a/Marlin/example_configurations/makibox/Configuration_adv.h
+++ b/Marlin/example_configurations/makibox/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/example_configurations/tvrrug/Round2/Configuration_adv.h b/Marlin/example_configurations/tvrrug/Round2/Configuration_adv.h
index a259f420a862731d68a935a51639cfc0e9fe7545..c9601c6c746e3c1334f109c5ba9e58e812f026eb 100644
--- a/Marlin/example_configurations/tvrrug/Round2/Configuration_adv.h
+++ b/Marlin/example_configurations/tvrrug/Round2/Configuration_adv.h
@@ -589,6 +589,31 @@
#if ENABLED(LIN_ADVANCE)
#define LIN_ADVANCE_K 75
+
+ /**
+ * Some Slicers produce Gcode with randomly jumping extrusion widths occasionally.
+ * For example within a 0.4mm perimeter it may produce a single segment of 0.05mm width.
+ * While this is harmless for normal printing (the fluid nature of the filament will
+ * close this very, very tiny gap), it throws off the LIN_ADVANCE pressure adaption.
+ *
+ * For this case LIN_ADVANCE_E_D_RATIO can be used to set the extrusion:distance ratio
+ * to a fixed value. Note that using a fixed ratio will lead to wrong nozzle pressures
+ * if the slicer is using variable widths or layer heights within one print!
+ *
+ * This option sets the default E:D ratio at startup. Use `M905` to override this value.
+ *
+ * Example: `M905 W0.4 H0.2 D1.75`, where:
+ * - W is the extrusion width in mm
+ * - H is the layer height in mm
+ * - D is the filament diameter in mm
+ *
+ * Set to 0 to auto-detect the ratio based on given Gcode G1 print moves.
+ *
+ * Slic3r (including Prusa Slic3r) produces Gcode compatible with the automatic mode.
+ * Cura (as of this writing) may produce Gcode incompatible with the automatic mode.
+ */
+ #define LIN_ADVANCE_E_D_RATIO 0 // The calculated ratio (or 0) according to the formula W * H / ((D / 2) ^ 2 * PI)
+ // Example: 0.4 * 0.2 / ((1.75 / 2) ^ 2 * PI) = 0.033260135
#endif
// @section leveling
diff --git a/Marlin/planner.cpp b/Marlin/planner.cpp
index 459e0b11d58ba4b9b056bad550d7f52346394adb..ec81cd300d753223f17378786ac7a36077e28bef 100644
--- a/Marlin/planner.cpp
+++ b/Marlin/planner.cpp
@@ -142,6 +142,7 @@ float Planner::previous_speed[NUM_AXIS],
#if ENABLED(LIN_ADVANCE)
float Planner::extruder_advance_k = LIN_ADVANCE_K,
+ Planner::advance_ed_ratio = LIN_ADVANCE_E_D_RATIO,
Planner::position_float[NUM_AXIS] = { 0 };
#endif
@@ -1324,7 +1325,12 @@ void Planner::_buffer_line(const float &a, const float &b, const float &c, const
&& (uint32_t)esteps != block->step_event_count
&& de_float > 0.0;
if (block->use_advance_lead)
- block->abs_adv_steps_multiplier8 = lround(extruder_advance_k * (de_float / mm_D_float) * block->nominal_speed / (float)block->nominal_rate * axis_steps_per_mm[E_AXIS_N] * 256.0);
+ block->abs_adv_steps_multiplier8 = lround(
+ extruder_advance_k
+ * (UNEAR_ZERO(advance_ed_ratio) ? de_float / mm_D_float : advance_ed_ratio) // Use the fixed ratio, if set
+ * (block->nominal_speed / (float)block->nominal_rate)
+ * axis_steps_per_mm[E_AXIS_N] * 256.0
+ );
#elif ENABLED(ADVANCE)
@@ -1478,14 +1484,3 @@ void Planner::refresh_positioning() {
}
#endif
-
-#if ENABLED(LIN_ADVANCE)
-
- void Planner::advance_M905(const float &k) {
- if (k >= 0.0) extruder_advance_k = k;
- SERIAL_ECHO_START;
- SERIAL_ECHOPAIR("Advance factor: ", extruder_advance_k);
- SERIAL_EOL;
- }
-
-#endif
diff --git a/Marlin/planner.h b/Marlin/planner.h
index 3e8609a904dff43e3da935258ef901101e6c07d7..c002c9977ba3cc4b30ae08c7b4484d28c418b69f 100644
--- a/Marlin/planner.h
+++ b/Marlin/planner.h
@@ -210,6 +210,7 @@ class Planner {
#if ENABLED(LIN_ADVANCE)
static float position_float[NUM_AXIS];
static float extruder_advance_k;
+ static float advance_ed_ratio;
#endif
#if ENABLED(ULTRA_LCD)
@@ -266,7 +267,9 @@ class Planner {
#endif
#if ENABLED(LIN_ADVANCE)
- void advance_M905(const float &k);
+ static void set_extruder_advance_k(const float &k) { extruder_advance_k = k; };
+ static float get_extruder_advance_k() { return extruder_advance_k; };
+ static void set_advance_ed_ratio(const float &ratio) { advance_ed_ratio = ratio; };
#endif
/**