This is very frustrating. I know I can print if I can get the calibration sorted out. I don't see my way through this without outside intervention (I'll speak to Quentin tomorrow, it's Friday evening so I won't bother him...)
I have discovered the following: I'm not the first to experience these type of problems. On the builders forum (on Quentins website) there are more people describing similar issues. One common cause seems to be reversed wiring on the steppers, and one case of reversed X and Y motor connections.
My X and Y motors are connected right way round. The four wires per motor might be the wrong way round, the document I followed (referenced in an early RAMPS post) has got the wiring the other way round than the RepRapWiki RAMPS wiring page. Mine is connected with the black wires towards the USB connector.
The Z-axis works properly (going DOWN when homing). The homing works perfectly (rotating counterclockwise from a position over the bed, to the home position). The extruder is however the wrong way round (I have to push the REVERSE button on Pronterface to feed the filament towards the print head). This might just be a case of the new extruder large drive gear having its teeth towards the inside of the wheel reversing the rotation direction than the original extruder the software was written for.
Just to make sure, I reversed the wiring order on the X and Y motors, and then the printer tries to home CLOCKWISE (as I expected), which physically it cannot do. So I'm still stumped.
Check if your endstops are on the correct pins on your RAMPS.
ReplyDeleteX is the top wheel and Y the bottom.
On my RAMPS, X is on the inside of the board, 2nd row of pins.