Hi, this is my first post here.
I'm finish building my first 3d printer (prusa i3).
When I testing my printer manually in pronterface everything works fine.
X axis homing to 0, (min endstopper on the left)
Y axis homing to 0, (min endstopper on the back of the printer)
Z axis homing to 0, (min endstopper on the bottom part of the printer)
So everything seems to be set up right.
But when I start printing something goes wrong;
I load the g code and press print, all 3 axis homing perfectly,but then after homing to 0 the z axis starts moving down, pushing the endstopper down and the extruder into the bed. if i pause the print an move the z axis up to 0 again the rest of the print goes on without a problem.
To be specific the z axis finds home, stops, an then moves 10-11mm in the negative direction, stops and waits for the extruder temp to hit 185(PLA) and then starts printing - the rest of the print goes on without any problem.
Here is the first part of the g code:
; generated by Slic3r 1.0.0RC2 on 2014-08-21 at 12:33:33
; layer_height = 0.3
; perimeters = 3
; top_solid_layers = 3
; bottom_solid_layers = 3
; fill_density = 0.4
; perimeter_speed = 30
; infill_speed = 60
; travel_speed = 130
; nozzle_diameter = 0.4
; filament_diameter = 1.75
; extrusion_multiplier = 1
; perimeters extrusion width = 0.40mm
; infill extrusion width = 0.42mm
; solid infill extrusion width = 0.42mm
; top infill extrusion width = 0.42mm
; first layer extrusion width = 0.80mm
G21 ; set units to millimeters
M107
M104 S185 ; set temperature
G28 ; home all axes
G1 Z0 F5000 ; lift nozzle
M109 S185 ; wait for temperature to be reached
G90 ; use absolute coordinates
G92 E0
M82 ; use absolute distances for extrusion
G1 F1800.000 E-1.00000
G92 E0
G1 Z0.400 F7800.000
G1 X85.920 Y66.270 F7800.000
G1 E1.00000 F1800.000
G1 X86.750 Y65.250 E1.15618 F540.000
G1 X87.770 Y64.420 E1.31236
G1 X88.930 Y63.800 E1.46857
G1 X90.190 Y63.410 E1.62522
G1 X91.500 Y63.290 E1.78145
G1 X96.500 Y63.290 E2.37528
G1 X97.810 Y63.410 E2.53151
G1 X99.070 Y63.800 E2.68816
G1 X100.230 Y64.420 E2.84437
G1 X101.250 Y65.250 E3.00055
G1 X102.080 Y66.270 E3.15673
G1 X102.700 Y67.430 E3.31294
G1 X103.090 Y68.690 E3.46959
G1 X103.210 Y70.000 E3.62582
G1 X103.210 Y75.000 E4.21965
G1 X103.090 Y76.310 E4.37588
G1 X102.700 Y77.570 E4.53253
G1 X102.080 Y78.730 E4.68874
G1 X101.250 Y79.750 E4.84492
G1 X100.230 Y80.580 E5.00110
G1 X99.070 Y81.200 E5.15731
G1 X97.810 Y81.590 E5.31396
G1 X96.500 Y81.710 E5.47020
G1 X91.500 Y81.710 E6.06402
G1 X90.190 Y81.590 E6.22026
G1 X88.930 Y81.200 E6.37690
G1 X87.770 Y80.580 E6.53312
G1 X86.750 Y79.750 E6.68930
G1 X85.920 Y78.730 E6.84547
G1 X85.300 Y77.570 E7.00169
G1 X84.910 Y76.310 E7.15833
G1 X84.790 Y75.000 E7.31457
G1 X84.790 Y70.000 E7.90839
G1 X84.910 Y68.690 E8.06463
G1 X85.300 Y67.430 E8.22128
G1 X85.870 Y66.364 E8.36477
G1 F1800.000 E7.36477
G92 E0
G1 X93.328 Y71.828 F7800.000
G1 E1.00000 F1800.000
G1 X94.672 Y71.828 E1.15954 F540.000
G1 X94.672 Y73.172 E1.31909
G1 X93.328 Y73.172 E1.47863
G1 X93.328 Y71.935 E1.62546
G1 X92.614 Y71.114 F7800.000
G1 X95.386 Y71.114 E1.95464 F540.000
......
And some of the codes in Marlins Configuration.h file I use:
// The pullups are needed if you directly connect a mechanical endswitch between the signal and ground pins.
const bool X_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Y_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Z_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool X_MAX_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Y_MAX_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Z_MAX_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
//#define DISABLE_MAX_ENDSTOPS
//#define DISABLE_MIN_ENDSTOPS
// Disable max endstops for compatibility with endstop checking routine
#if defined(COREXY) && !defined(DISABLE_MAX_ENDSTOPS)
#define DISABLE_MAX_ENDSTOPS
#endif
// For Inverting Stepper Enable Pins (Active Low) use 0, Non Inverting (Active High) use 1
#define X_ENABLE_ON 0
#define Y_ENABLE_ON 0
#define Z_ENABLE_ON 0
#define E_ENABLE_ON 0 // For all extruders
// Disables axis when it's not being used.
#define DISABLE_X false
#define DISABLE_Y false
#define DISABLE_Z false
#define DISABLE_E false // For all extruders
#define INVERT_X_DIR false // for Mendel set to false, for Orca set to true
#define INVERT_Y_DIR false // for Mendel set to true, for Orca set to false
#define INVERT_Z_DIR true // for Mendel set to false, for Orca set to true
#define INVERT_E0_DIR false // for direct drive extruder v9 set to true, for geared extruder set to false
#define INVERT_E1_DIR false // for direct drive extruder v9 set to true, for geared extruder set to false
#define INVERT_E2_DIR false // for direct drive extruder v9 set to true, for geared extruder set to false
// ENDSTOP SETTINGS:
// Sets direction of endstops when homing; 1=MAX, -1=MIN
#define X_HOME_DIR -1
#define Y_HOME_DIR -1
#define Z_HOME_DIR -1
#define min_software_endstops true // If true, axis won't move to coordinates less than HOME_POS.
#define max_software_endstops true // If true, axis won't move to coordinates greater than the defined lengths below.
----
//// MOVEMENT SETTINGS
#define NUM_AXIS 4 // The axis order in all axis related arrays is X, Y, Z, E
#define HOMING_FEEDRATE {50*60, 50*60, 150, 0} // set the homing speeds (mm/min)
// default settings
#define DEFAULT_AXIS_STEPS_PER_UNIT {80,80,4000,70} // default steps per unit for Ultimaker
#define DEFAULT_MAX_FEEDRATE {250, 250, 2, 22} // (mm/sec)
#define DEFAULT_MAX_ACCELERATION {1000,1000,5,1000} // 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 500 // X, Y, Z and E max acceleration in mm/s^2 for printing moves
#define DEFAULT_RETRACT_ACCELERATION 500 // X, Y, Z and E max acceleration in mm/s^2 for retracts
----
I am really stuck here so all help is much appreciated.