diff --git a/Firmware/first_lay_cal.cpp b/Firmware/first_lay_cal.cpp
index 5e61f1f061..7f23431c91 100644
--- a/Firmware/first_lay_cal.cpp
+++ b/Firmware/first_lay_cal.cpp
@@ -37,12 +37,31 @@ static constexpr float spacing(float layer_height, float extrusion_width, float
 static void lay1cal_common_enqueue_loop(const char * const * cmd_sequence, const uint8_t steps) {
     for (uint8_t i = 0; i < steps; ++i)
     {
-        enquecommand_P(static_cast<char*>(pgm_read_ptr(cmd_sequence + i)));
+        void * const pgm_ptr = pgm_read_ptr(cmd_sequence + i);
+
+        // M702 is currently only used with MMU enabled
+        if (pgm_ptr == MSG_M702 && !MMU2::mmu2.Enabled()) {
+            continue;
+        }
+
+        enquecommand_P(static_cast<char*>(pgm_ptr));
     }
 }
 
-static const char extrude_fmt[] PROGMEM = "G1 X%d Y%d E%-.5f";
-static const char zero_extrusion[] PROGMEM = "G92 E0";
+static const char extrude_fmt_X[] PROGMEM = "G1X%.4fE%.4f";
+static const char extrude_fmt_Y[] PROGMEM = "G1Y%.4fE%.4f";
+static const char zero_extrusion[] PROGMEM = "G92E0";
+static const char feedrate_F1080[] PROGMEM = "G1F1080";
+#ifndef NEW_FIRST_LAYER_CAL
+static constexpr int8_t invert = 1;
+static constexpr float short_length = 20;
+static constexpr float square_width = short_length;
+#else
+static constexpr int8_t invert = -1;
+static constexpr float short_length = 13.2812; //max_pos[1]/2 / meander * 2
+static constexpr float square_width = short_length*2;
+#endif //NEW_FIRST_LAYER_CAL
+static constexpr float long_length = 150;
 
 //! @brief Wait for preheat
 void lay1cal_wait_preheat()
@@ -72,8 +91,8 @@ bool lay1cal_load_filament(uint8_t filament)
     if (MMU2::mmu2.Enabled())
     {
         enquecommand_P(MSG_M83);
-        enquecommand_P(PSTR("G1 Y-3 F1000"));
-        enquecommand_P(PSTR("G1 Z0.4 F1000"));
+        enquecommand_P(PSTR("G1Y-3F1000"));
+        enquecommand_P(PSTR("G1Z0.4"));
 
         uint8_t currentTool = MMU2::mmu2.get_current_tool();
         if(currentTool == filament ){
@@ -96,22 +115,19 @@ bool lay1cal_load_filament(uint8_t filament)
 //! @param extrusion_width the width of the extrusion layer
 void lay1cal_intro_line(bool extraPurgeNeeded, float layer_height, float extrusion_width)
 {
-    static const char cmd_intro_mmu_3[] PROGMEM = "G1 X55 E29 F1073";
-    static const char cmd_intro_mmu_4[] PROGMEM = "G1 X5 E29 F1800";
-    static const char cmd_intro_mmu_5[] PROGMEM = "G1 X55 E8 F2000";
-    static const char cmd_intro_mmu_6[] PROGMEM = "G1 Z0.3 F1000";
-    static const char cmd_intro_mmu_8[] PROGMEM = "G1 X240 E25  F2200";
-    static const char cmd_intro_mmu_9[] PROGMEM = "G1 Y-2 F1000";
-    static const char cmd_intro_mmu_10[] PROGMEM = "G1 X55 E25 F1400";
-    static const char cmd_intro_mmu_11[] PROGMEM = "G1 Z0.2 F1000";
-    static const char cmd_intro_mmu_12[] PROGMEM = "G1 X5 E4 F1000";
-
-    static const char * const intro_mmu_cmd[] PROGMEM =
+    static const char cmd_intro_mmu_3[] PROGMEM = "G1X55E29F1073";
+    static const char cmd_intro_mmu_4[] PROGMEM = "G1X5E29F1800";
+    static const char cmd_intro_mmu_5[] PROGMEM = "G1X55E8F2000";
+    static const char cmd_intro_mmu_6[] PROGMEM = "G1Z0.3F1000";
+    static const char cmd_intro_mmu_8[] PROGMEM = "G1X240E25F2200";
+    static const char cmd_intro_mmu_9[] PROGMEM = "G1Y-2F1000";
+    static const char cmd_intro_mmu_10[] PROGMEM = "G1X202.5E8F1400";
+    static const char cmd_intro_mmu_11[] PROGMEM = "G1Z0.2";
+    static const char * const cmd_intro_mmu[] PROGMEM =
     {
         // first 2 items are only relevant if filament was not loaded - i.e. extraPurgeNeeded == true
         cmd_intro_mmu_3,
         cmd_intro_mmu_4,
-
         cmd_intro_mmu_5,
         cmd_intro_mmu_6,
         zero_extrusion,
@@ -119,42 +135,42 @@ void lay1cal_intro_line(bool extraPurgeNeeded, float layer_height, float extrusi
         cmd_intro_mmu_9,
         cmd_intro_mmu_10,
         cmd_intro_mmu_11,
-        cmd_intro_mmu_12,
     };
 
     if (MMU2::mmu2.Enabled())
     {
-        for (uint8_t i = (extraPurgeNeeded ? 0 : 2); i < (sizeof(intro_mmu_cmd)/sizeof(intro_mmu_cmd[0])); ++i)
+        for (uint8_t i = (extraPurgeNeeded ? 0 : 2); i < (sizeof(cmd_intro_mmu)/sizeof(cmd_intro_mmu[0])); ++i)
         {
-            enquecommand_P(static_cast<char*>(pgm_read_ptr(&intro_mmu_cmd[i])));
+            enquecommand_P(static_cast<char*>(pgm_read_ptr(&cmd_intro_mmu[i])));
         }
     }
     else
     {
-        static const char fmt1[] PROGMEM = "G1 X%d E%-.3f F1000";
-        enquecommandf_P(fmt1, 60, count_e(layer_height, extrusion_width * 4.f, 60));
-        enquecommandf_P(fmt1, 100, count_e(layer_height, extrusion_width * 8.f, 40));
+        enquecommand_P(feedrate_F1080); //fixed velocity for the intro line
+        enquecommandf_P(extrude_fmt_X, 60.f, count_e(layer_height, extrusion_width * 4.f, 60));
+        enquecommandf_P(extrude_fmt_X, 202.5f, count_e(layer_height, extrusion_width * 8.f, 142.5));
     }
 }
 
 //! @brief Setup for printing meander
 void lay1cal_before_meander()
 {
-    static const char cmd_pre_meander_2[] PROGMEM = "G90"; //use absolute coordinates
-    static const char cmd_pre_meander_4[] PROGMEM = "G1 E-1.5 F2100";
-    static const char cmd_pre_meander_5[] PROGMEM = "G1 Z5 F7200";
-    static const char cmd_pre_meander_6[] PROGMEM = "M204 S1000"; //set acceleration
-    static const char cmd_pre_meander_7[] PROGMEM = "G1 F4000";
+#ifndef NEW_FIRST_LAYER_CAL
+    static const char cmd_pre_meander_4[] PROGMEM = "G1E-1.5F2100";
+    static const char cmd_pre_meander_5[] PROGMEM = "G1Z5F7200";
+#endif //NEW_FIRST_LAYER_CAL
+    static const char cmd_pre_meander_6[] PROGMEM = "M204S1000"; //set acceleration
 
     static const char * const cmd_pre_meander[] PROGMEM =
     {
             zero_extrusion,
-            cmd_pre_meander_2,
+            MSG_G90,
             MSG_M83, // use relative distances for extrusion
+#ifndef NEW_FIRST_LAYER_CAL
             cmd_pre_meander_4,
             cmd_pre_meander_5,
+#endif //NEW_FIRST_LAYER_CAL
             cmd_pre_meander_6,
-            cmd_pre_meander_7,
     };
 
     lay1cal_common_enqueue_loop(cmd_pre_meander, (sizeof(cmd_pre_meander)/sizeof(cmd_pre_meander[0])));
@@ -163,88 +179,86 @@ void lay1cal_before_meander()
 //! @brief Print meander start
 void lay1cal_meander_start(float layer_height, float extrusion_width)
 {
-    enquecommand_P(PSTR("G1 X50 Y155"));
-
-    static const char fmt1[] PROGMEM = "G1 Z%-.3f F7200";
+#ifndef NEW_FIRST_LAYER_CAL
+    enquecommand_P(PSTR("G1X50Y155"));
+#endif //_NEW_FIRST_LAYER_CAL
+    static const char fmt1[] PROGMEM = "G1Z%.2f";
     enquecommandf_P(fmt1, layer_height);
-
-    enquecommand_P(PSTR("G1 F1080"));
-
-    enquecommandf_P(extrude_fmt,  75, 155, count_e(layer_height, extrusion_width * 4.f, 25));
-    enquecommandf_P(extrude_fmt, 100, 155, count_e(layer_height, extrusion_width * 2.f, 25));
-    enquecommandf_P(extrude_fmt, 200, 155, count_e(layer_height, extrusion_width, 100));
-    enquecommandf_P(extrude_fmt, 200, 135, count_e(layer_height, extrusion_width, 20));
+    enquecommand_P(feedrate_F1080);
+    enquecommand_P(MSG_G91); //enable relative XYZ
+#ifdef NEW_FIRST_LAYER_CAL
+    enquecommandf_P(extrude_fmt_Y, short_length, count_e(layer_height, extrusion_width, short_length));
+    enquecommandf_P(extrude_fmt_X, long_length*invert, count_e(layer_height, extrusion_width, long_length));
+    enquecommandf_P(extrude_fmt_Y, -short_length*invert, count_e(layer_height, extrusion_width, short_length));
+#else
+    enquecommandf_P(extrude_fmt_X, 25.f*invert, count_e(layer_height, extrusion_width * 4.f, 25));
+    enquecommandf_P(extrude_fmt_X, 25.f*invert, count_e(layer_height, extrusion_width * 2.f, 25));
+    enquecommandf_P(extrude_fmt_X, 100.f*invert, count_e(layer_height, extrusion_width, 100));
+    enquecommandf_P(extrude_fmt_Y, -20.f*invert, count_e(layer_height, extrusion_width, 20));
+#endif //_NEW_FIRST_LAYER_CAL
 }
 
 //! @brief Print meander
 //! @param cmd_buffer character buffer needed to format gcodes
 void lay1cal_meander(float layer_height, float extrusion_width)
 {
-    const float short_length = 20;
-    float long_length = 150;
     const float long_extrusion = count_e(layer_height, extrusion_width, long_length);
     const float short_extrusion = count_e(layer_height, extrusion_width, short_length);
 
-    uint8_t y_pos = 135;
-    uint8_t x_pos = 50;
-    for(uint8_t i = 0; i <= 4; ++i)
+    for(int8_t i = 0, xdir = -invert; i <= 4; i++, xdir = -xdir)
     {
-        enquecommandf_P(extrude_fmt, x_pos, y_pos, long_extrusion);
-
-        y_pos -= short_length;
-
-        enquecommandf_P(extrude_fmt, x_pos, y_pos, short_extrusion);
-
-        x_pos += long_length;
-
-        long_length = -long_length;
+        enquecommandf_P(extrude_fmt_X, xdir * long_length, long_extrusion);
+        enquecommandf_P(extrude_fmt_Y, invert * -short_length, short_extrusion);
     }
+#ifdef NEW_FIRST_LAYER_CAL
+    constexpr float mid_length = 0.5f * long_length - 0.5f * square_width;
+    const float mid_extrusion = count_e(layer_height, extrusion_width, mid_length);
+    enquecommandf_P(extrude_fmt_X, -mid_length, mid_extrusion); //~Middle of bed X125
+    enquecommandf_P(extrude_fmt_Y, short_length, short_extrusion); //~Middle of bed Y105
+#endif //NEW_FIRST_LAYER_CAL
 
 }
 
 //! @brief Print square
 //!
-//! This function needs to be called 4 times with step of 0,4,8,12
+//! This function enqueues 4 lines of the square, so it needs to be called multiple times
 //!
 //! @param cmd_buffer character buffer needed to format gcodes
-//! @param i iteration
-void lay1cal_square(uint8_t step, float layer_height, float extrusion_width)
+void lay1cal_square(float layer_height, float extrusion_width)
 {
-    const float long_length = 20;
-    const float short_length = spacing(layer_height, extrusion_width);
-    const float long_extrusion = count_e(layer_height, extrusion_width, long_length);
-    const float short_extrusion = count_e(layer_height, extrusion_width, short_length);
-    static const char fmt1[] PROGMEM = "G1 X%d Y%-.2f E%-.3f";
+    const float Y_spacing = spacing(layer_height, extrusion_width);
+    const float long_extrusion = count_e(layer_height, extrusion_width, square_width);
+    const float short_extrusion = count_e(layer_height, extrusion_width, Y_spacing);
 
-    for (uint8_t i = step; i < step+4; ++i)
+    for (uint8_t i = 0; i < 4; i++)
     {
-        enquecommandf_P(fmt1, 70, (35 - i*short_length * 2), long_extrusion);
-        enquecommandf_P(fmt1, 70, (35 - (2 * i + 1)*short_length), short_extrusion);
-        enquecommandf_P(fmt1, 50, (35 - (2 * i + 1)*short_length), long_extrusion);
-        enquecommandf_P(fmt1, 50, (35 - (i + 1)*short_length * 2), short_extrusion);
+        enquecommandf_P(extrude_fmt_X, square_width*invert, long_extrusion);
+        enquecommandf_P(extrude_fmt_Y, -Y_spacing*invert, short_extrusion);
+        enquecommandf_P(extrude_fmt_X, -square_width*invert, long_extrusion);
+        enquecommandf_P(extrude_fmt_Y, -Y_spacing*invert, short_extrusion);
     }
 }
 
-void lay1cal_finish(bool mmu_enabled)
+void lay1cal_finish()
 {
-    static const char cmd_cal_finish_1[] PROGMEM = "G1 E-0.075 F2100"; //retract
-    static const char cmd_cal_finish_2[] PROGMEM = "M104 S0"; // turn off temperature
-    static const char cmd_cal_finish_3[] PROGMEM = "M140 S0"; // turn off heatbed
-    static const char cmd_cal_finish_4[] PROGMEM = "G1 Z10 F1300"; //lift Z
-    static const char cmd_cal_finish_5[] PROGMEM = "G1 X10 Y180 F4000"; //Go to parking position
+    static const char cmd_cal_finish_3[] PROGMEM = "G1E-0.075F2100"; // Retract
+    static const char cmd_cal_finish_4[] PROGMEM = "M140S0";         // Turn off bed heater
+    static const char cmd_cal_finish_5[] PROGMEM = "G1Z10F1300";     // Lift Z
+    static const char cmd_cal_finish_6[] PROGMEM = "G1X10Y180F4000"; // Go to parking position
+    static const char cmd_cal_finish_8[] PROGMEM = "M104S0";         // Turn off hotend heater
 
     static const char * const cmd_cal_finish[] PROGMEM =
     {
-            MSG_M107, // turn off printer fan
-            cmd_cal_finish_1,
-            cmd_cal_finish_2,
-            cmd_cal_finish_3,
-            cmd_cal_finish_4,
-            cmd_cal_finish_5
+        MSG_G90,          // Set to Absolute Positioning
+        MSG_M107,         // Turn off printer fan
+        cmd_cal_finish_3, // Retract
+        cmd_cal_finish_4, // Turn off bed heater
+        cmd_cal_finish_5, // Lift Z
+        cmd_cal_finish_6, // Go to parking position
+        MSG_M702,         // Unload filament (MMU only)
+        cmd_cal_finish_8, // Turn off hotend heater
+        MSG_M84           // Disable stepper motors
     };
 
     lay1cal_common_enqueue_loop(cmd_cal_finish, (sizeof(cmd_cal_finish)/sizeof(cmd_cal_finish[0])));
-
-    if (mmu_enabled) enquecommand_P(MSG_M702); //unload from nozzle
-    enquecommand_P(MSG_M84);// disable motors
 }
diff --git a/Firmware/first_lay_cal.h b/Firmware/first_lay_cal.h
index 1e2dd624a0..7a2b80f803 100644
--- a/Firmware/first_lay_cal.h
+++ b/Firmware/first_lay_cal.h
@@ -12,7 +12,7 @@ void lay1cal_intro_line(bool skipExtraPurge, float layer_height, float extrusion
 void lay1cal_before_meander();
 void lay1cal_meander_start(float layer_height, float extrusion_width);
 void lay1cal_meander(float layer_height, float extrusion_width);
-void lay1cal_square(uint8_t step, float layer_height, float extrusion_width);
-void lay1cal_finish(bool mmu_enabled);
+void lay1cal_square(float layer_height, float extrusion_width);
+void lay1cal_finish();
 
 #endif /* FIRMWARE_FIRST_LAY_CAL_H_ */
diff --git a/Firmware/messages.cpp b/Firmware/messages.cpp
index 75303059b8..1c5a31c309 100644
--- a/Firmware/messages.cpp
+++ b/Firmware/messages.cpp
@@ -428,6 +428,8 @@ const char MSG_FILAMENT_RUNOUT_DETECTED[] PROGMEM_N1 = "Filament runout detected
 // Common G-gcodes
 const char G1_E_F2700[] PROGMEM_N1 = "G1 E%-.3f F2700";
 const char G28W[] PROGMEM_N1 = "G28 W";
+const char MSG_G90[] PROGMEM_N1 = "G90";
+const char MSG_G91[] PROGMEM_N1 = "G91";
 const char MSG_M23[] PROGMEM_N1 = "M23 %s";
 const char MSG_M24[] PROGMEM_N1 = "M24";
 const char MSG_M83[] PROGMEM_N1 = "M83";
diff --git a/Firmware/messages.h b/Firmware/messages.h
index 4d1e6c99e7..8ce0568406 100644
--- a/Firmware/messages.h
+++ b/Firmware/messages.h
@@ -430,6 +430,8 @@ extern const char MSG_FILAMENT_RUNOUT_DETECTED[];
 // Common G-gcodes
 extern const char G1_E_F2700[];
 extern const char G28W[];
+extern const char MSG_G90[];
+extern const char MSG_G91[];
 extern const char MSG_M23[];
 extern const char MSG_M24[];
 extern const char MSG_M83[];
diff --git a/Firmware/ultralcd.cpp b/Firmware/ultralcd.cpp
index df78267ee3..0faec8a907 100644
--- a/Firmware/ultralcd.cpp
+++ b/Firmware/ultralcd.cpp
@@ -857,19 +857,13 @@ void lcd_commands()
                 lay1cal_meander(layer_height, extrusion_width);
                 break;
             case 6:
-                lay1cal_square(0, layer_height, extrusion_width);
-                break;
             case 5:
-                lay1cal_square(4, layer_height, extrusion_width);
-                break;
             case 4:
-                lay1cal_square(8, layer_height, extrusion_width);
-                break;
             case 3:
-                lay1cal_square(12, layer_height, extrusion_width);
+                lay1cal_square(layer_height, extrusion_width);
                 break;
             case 2:
-                lay1cal_finish(MMU2::mmu2.Enabled());
+                lay1cal_finish();
                 break;
             case 1:
                 lcd_setstatuspgm(MSG_WELCOME);
diff --git a/Firmware/variants/MK25-RAMBo10a.h b/Firmware/variants/MK25-RAMBo10a.h
index 4e02bf14f0..77cced0bed 100644
--- a/Firmware/variants/MK25-RAMBo10a.h
+++ b/Firmware/variants/MK25-RAMBo10a.h
@@ -24,6 +24,7 @@
 
 #define HEATBED_V2
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define TACH0PULLUP
 
 // Uncomment the below for the E3D PT100 temperature sensor (with or without PT100 Amplifier)
diff --git a/Firmware/variants/MK25-RAMBo13a.h b/Firmware/variants/MK25-RAMBo13a.h
index 3b7a81408c..9f081885f5 100644
--- a/Firmware/variants/MK25-RAMBo13a.h
+++ b/Firmware/variants/MK25-RAMBo13a.h
@@ -24,6 +24,7 @@
 
 #define HEATBED_V2
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define TACH0PULLUP
 
 // Uncomment the below for the E3D PT100 temperature sensor (with or without PT100 Amplifier)
diff --git a/Firmware/variants/MK25S-RAMBo10a.h b/Firmware/variants/MK25S-RAMBo10a.h
index 906ba6859c..b047cb00d3 100644
--- a/Firmware/variants/MK25S-RAMBo10a.h
+++ b/Firmware/variants/MK25S-RAMBo10a.h
@@ -24,6 +24,7 @@
 
 #define HEATBED_V2
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define TACH0PULLUP
 
 // Uncomment the below for the E3D PT100 temperature sensor (with or without PT100 Amplifier)
diff --git a/Firmware/variants/MK25S-RAMBo13a.h b/Firmware/variants/MK25S-RAMBo13a.h
index bb3ad41af9..9ef7f3bd7b 100644
--- a/Firmware/variants/MK25S-RAMBo13a.h
+++ b/Firmware/variants/MK25S-RAMBo13a.h
@@ -24,6 +24,7 @@
 
 #define HEATBED_V2
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define TACH0PULLUP
 
 // Uncomment the below for the E3D PT100 temperature sensor (with or without PT100 Amplifier)
diff --git a/Firmware/variants/MK3-E3DREVO.h b/Firmware/variants/MK3-E3DREVO.h
index 9efb587ddc..9232f84627 100644
--- a/Firmware/variants/MK3-E3DREVO.h
+++ b/Firmware/variants/MK3-E3DREVO.h
@@ -23,6 +23,7 @@
 // Electronics
 #define MOTHERBOARD BOARD_EINSY_1_0a
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define HAS_SECOND_SERIAL_PORT
 
 
diff --git a/Firmware/variants/MK3-E3DREVO_HF_60W.h b/Firmware/variants/MK3-E3DREVO_HF_60W.h
index 5ec1bdb8db..ace4553d55 100644
--- a/Firmware/variants/MK3-E3DREVO_HF_60W.h
+++ b/Firmware/variants/MK3-E3DREVO_HF_60W.h
@@ -23,6 +23,7 @@
 // Electronics
 #define MOTHERBOARD BOARD_EINSY_1_0a
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define HAS_SECOND_SERIAL_PORT
 
 
diff --git a/Firmware/variants/MK3.h b/Firmware/variants/MK3.h
index b9ab1ed3c0..8b0651f257 100644
--- a/Firmware/variants/MK3.h
+++ b/Firmware/variants/MK3.h
@@ -23,6 +23,7 @@
 // Electronics
 #define MOTHERBOARD BOARD_EINSY_1_0a
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define HAS_SECOND_SERIAL_PORT
 
 
diff --git a/Firmware/variants/MK3S-E3DREVO.h b/Firmware/variants/MK3S-E3DREVO.h
index d426d7d7de..70aef3d4d2 100644
--- a/Firmware/variants/MK3S-E3DREVO.h
+++ b/Firmware/variants/MK3S-E3DREVO.h
@@ -22,6 +22,7 @@
 // Electronics
 #define MOTHERBOARD BOARD_EINSY_1_0a
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define HAS_SECOND_SERIAL_PORT
 
 // PSU
diff --git a/Firmware/variants/MK3S-E3DREVO_HF_60W.h b/Firmware/variants/MK3S-E3DREVO_HF_60W.h
index de86f6c027..cf576d82da 100644
--- a/Firmware/variants/MK3S-E3DREVO_HF_60W.h
+++ b/Firmware/variants/MK3S-E3DREVO_HF_60W.h
@@ -22,6 +22,7 @@
 // Electronics
 #define MOTHERBOARD BOARD_EINSY_1_0a
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define HAS_SECOND_SERIAL_PORT
 
 // PSU
diff --git a/Firmware/variants/MK3S.h b/Firmware/variants/MK3S.h
index 32ca987b02..6d2027671f 100644
--- a/Firmware/variants/MK3S.h
+++ b/Firmware/variants/MK3S.h
@@ -22,6 +22,7 @@
 // Electronics
 #define MOTHERBOARD BOARD_EINSY_1_0a
 #define STEEL_SHEET
+//#define NEW_FIRST_LAYER_CAL //from front to back
 #define HAS_SECOND_SERIAL_PORT
 
 // PSU