Help please. Dip switches and mach 3 settings

[cropwell]

Co-incidentally, while I was thinking about a reply during a cut, my Z axis limit switch wire caught, pulled and broke and tripped the limits. Fortunately it was a short job and after disabling the limits, I reran the job successfully. I now have that problem to attend to.

Your problem still sounds like an intermittent disconnect to your Z motor. I don't know what wires you used, but you need high flexibility wires which have many (32 for instance) strands in each conductor and flexible rubber insulation. Another consideration is the bend radius, which must be as large as practicable. The wires to the Z motor move around a lot more than any other stepper.

Also look at your solder joints. Wire at these points become embrittled and any vibration or movement can fracture them. I have all the wires to my motors fixed down with P clips to eliminate movement. Bad solder joints can be notoriously difficult to spot.

Relay clicking ? Can you give us a wiring diagram for your PWM connection? The relay can be disabled by an on board jumper, if you are not using the contacts. My PWM controller uses the BoB PWM output and Port 1 Pin 17 (Normally B axis Direction signal).