Stepper motors Z axis move very very slow (3 replies)

Hello all ,

I have a slight problem with my stepper motors of the z axis , they turn very very very slow when the axis goes down or up ( it takes 8 sec to move 10mm ) . There's no banding in the rod's , when i connect the motors on the x and y connections they work just fine . I just upgraded to these lead screws and all worked fine before , i have replaced the stepper driver but that did not help , i checked my configuration.h file but i cant see it there .Sorry for my english but i hope some one can help me out here . I post my configuration.h file to . I hope it is not the ramps board.


/**
* Default Axis Steps Per Unit (steps/mm)
* Override with M92
* X, Y, Z, E0 [, E1[, E2[, E3]]]
*/
#define DEFAULT_AXIS_STEPS_PER_UNIT { 158.6357, 158.6357, 800, 239.077 }

/**
* Default Max Feed Rate (mm/s)
* Override with M203
* X, Y, Z, E0 [, E1[, E2[, E3]]]
*/
#define DEFAULT_MAX_FEEDRATE {300, 300, 3.5, 25 }

/**
* Default Max Acceleration (change/s) change = mm/s
* (Maximum start speed for accelerated moves)
* Override with M201
* X, Y, Z, E0 [, E1[, E2[, E3]]]
*/
#define DEFAULT_MAX_ACCELERATION { 1500,1500,100,1000 }

/**
* Default Acceleration (change/s) change = mm/s
* Override with M204
*
* M204 P Acceleration
* M204 R Retract Acceleration
* M204 T Travel Acceleration
*/
#define DEFAULT_ACCELERATION 1000 // X, Y, Z and E acceleration for printing moves
#define DEFAULT_RETRACT_ACCELERATION 3000 // E acceleration for retracts
#define DEFAULT_TRAVEL_ACCELERATION 3000 // X, Y, Z acceleration for travel (non printing) moves

/**
* Default Jerk (mm/s)
*
* "Jerk" specifies the minimum speed change that requires acceleration.
* When changing speed and direction, if the difference is less than the
* value set here, it may happen instantaneously.
*/
#define DEFAULT_XJERK 10.0
#define DEFAULT_YJERK 10.0
#define DEFAULT_ZJERK 0.4
#define DEFAULT_EJERK 5.0