I received and built the printer last week but had issue installing the arduino mega on my room's old laptop (vista home premium)
So i tested this week end on a normal win 7 computer.
Guess what ?
Everything went fine until chapter 13.3, page 52 :
Press Home X, then move the x axis back and forth. The axis will only move in positive direction if the Home X button is not pressed.
- Press Home Y, move the y axis back and forth.
- Press Home Z
At first sight, I did not understand what was these steps for, as I had no X,Y nor Extruder motor moving or making any noise at all. Only the Z-axis which was described as tricky was working fine, only down but no wobbles, no noise, perfect as in the videos.
Troubleshoot steps:
0/ I checked cables and connectors: the RAMP Shield was not fully attached to the MEGA Board [ok]
1/ I swapped stepper motors cables to the Z connector: all 3 motors were working fine [ok]
2/ I checked Optosensors and happily swapped the cables (each sensors for each motors), and Z axis could go up and down [ok]
3/ I swapped Y and Z steppers drivers, the Y axis motor worked but Z axis was not responding [ko]
4/ After having browsed the forum and found 2 or 3 identical issues, i decided to set the calibrations screw to one quarter, X an Y motors worked [ok]
5/ X,Y axis were going too far (shining through plastic).Glued some black paper on it [ok]
6/ I tried to test the rest:
fans control [ok],
bed heating [ok],
extruder [ok],
printing the calibration object without PLA : extruder motor works !! [ok]
(Thanks Guillaume to have explained it worked only after having reached a certain temperature)
7/ I tried to change the calibration screw on X, and got strange cyclic vibrations as if the motor was trying to turn while being blocked [ko]
8/I swapped again the X axis stepper driver with the Z axis stepper driver and now the table is moving like a charm, [ok]
9/ Problem, the Z axis is wobbling like hell or not even moving.[ko]
10/ After several tests Z was still not moving, I tried to set the screw to the maximum but the screw is now turning 360° :/ [FAIL]
Can somebody help me ? I would like to get the exact reference of this stepper driver to replace it

Thanks in advance
Stephane