Adjusted the maximum acceleration of the Z axis to a sensible value

for the MK2 printer.

Firmware/variants/1_75mm_MK2-RAMBo10a-E3Dv6full.h

@@ -51,7 +51,7 @@ const bool Z_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic o
 #define NUM_AXIS 4 // The axis order in all axis related arrays is X, Y, Z, E
 #define HOMING_FEEDRATE {3000, 3000, 800, 0}  // set the homing speeds (mm/min)
 
-#define DEFAULT_MAX_FEEDRATE          {500, 500, 1000, 25}    // (mm/sec)
+#define DEFAULT_MAX_FEEDRATE          {500, 500, 24, 25}    // (mm/sec)
 #define DEFAULT_MAX_ACCELERATION      {9000,9000,1000,10000}    // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for Skeinforge 40+, for older versions raise them a lot.
 
 #define DEFAULT_ACCELERATION          3000    // X, Y, Z and E max acceleration in mm/s^2 for printing moves

Firmware/variants/1_75mm_MK2-RAMBo13a-E3Dv6full.h

@@ -51,7 +51,7 @@ const bool Z_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic o
 #define NUM_AXIS 4 // The axis order in all axis related arrays is X, Y, Z, E
 #define HOMING_FEEDRATE {3000, 3000, 800, 0}  // set the homing speeds (mm/min)
 
-#define DEFAULT_MAX_FEEDRATE          {500, 500, 1000, 25}    // (mm/sec)
+#define DEFAULT_MAX_FEEDRATE          {500, 500, 24, 25}    // (mm/sec)
 #define DEFAULT_MAX_ACCELERATION      {9000,9000,1000,10000}    // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for Skeinforge 40+, for older versions raise them a lot.
 
 #define DEFAULT_ACCELERATION          3000    // X, Y, Z and E max acceleration in mm/s^2 for printing moves