@Repetier, Thank you again for your support and continued patience with an obvious newby. As I have said, and will continue to say, receiving support this responsive, detailed, and timely, one-on-one from another country is, in my opinion, astoundingly good.(1) Your last reply provides very interesting and helpful information. I suspected, from your previous discussions on this forum, that my issue was crosstalk and examining the log verified this problem. I now set out to correct it....(2) I am using mechanical endstops, standard PCB containing microswitches. Triggering a Ymin endstop by hand, M119 (today) shows:15:41:38.268 : endstops hit: x_min:L y_min:H z_max:H Z-probe state:H
However, upon examination I find the Signal pin on the endstop goes to GND when triggered. Assuming the standard RAMPS 1.4 and the standard endstop PCB work together to provide this signal to the Arduino and the firmware sees the signal and (normally) behaves properly, is there a recommended way to invert this hard wired logic since you say (above) this is not a reliable method?(3) As I said, I replaced the Ymin cable with a shielded cable. That is, all 4 wires are physically wrapped with a metallic shield, which is wired to GND on both ends of the cable. While I have attempted to physically separate the endstop wires from the motor wires, they come in close proximity when connecting everything to the RAMPS PCB itself.(4) I am using a <font color="#0066cc">WYZworks Regulated Power Supply 12v 30a 360w</font> for the system, and tried adjust the Y motor pot. I have not found a setting for this pot which makes the bed difficult to move by hand, which suggests to me that I need more current to the Y motor? I have not the equipment to measure the voltage during motor movements, current to the motor during pulses, or capture and observe transient voltage spikes. I also reduced acceleration parameters (to 600) and yesterday's test resulted in only a few dropped Y movements. I consider this progress but still unacceptable as the print was significantly flawed.Since you so easily and correctly diagnosed this problem, there surely must be a solution because so many people are 3D printing successfully. Again, I appreciate your attention and continue to believe in your product!
