My machine has been running for some time now happily without any electrical noise issues. Everything is grounded to a common star ground point in my electrical cabinet, and this includes the shielded cable running from my stepper motors to the enclosure. From the connectors on the enclosure to the stepper drives, the same shielded cable is used, and the shielding is grounded to the big heatsink that the stepper drives are mounted to. My Kflop is grounded via the USB cable (I am assuming).

A few weeks ago I installed a Kanalog so that I could hook up my proximity sensors and therefore have a reliable means of zeroing and squaring up my machine. Because of this switch, I had to change how I connected to my Kflop, using JP5 instead of JP7. To make this connection, I cut a short length of I bought a RJ45-->Serial adaptor (similar to this: RJ45 to DB9 Female Modular Adapter - Black) , and then stuck the pins into one end of a Pheonix Contact that I had laying aorund.. similar to this: (1803675 Phoenix Contact | Mouser).

Everything works as I expect it to, however I now have a consistent issue with my motors clicking slightly while the machine is at rest. Sometimes when I'm running a file I can hear a clunk, which to sounds to me as if I have just lost steps (this is what my old machine used to sound like when it lost steps). Sure enough, when I go to check my 0,0 point that I have marked for reference on the table, it is slightly off. (the last little file I ran I ended up being .011 off in x and .02 off in Y)

Messing around with my stepper motor cabling, I have been able to induce noise by shaking them around, and so I have paid a lot of attention to ensuring that I have a good metal to metal connection between the shielded microphone connectors that I am using to connect the cable to the cabinet with. This morning I ground away all of the paint surrounding the connectors to be sure I was getting decent contact. I tested each connector with a continuity tester, and I have continuity between the all the the connectors and the box, and thus the main ground. This seems to make the clicking go away for the most part, but it still occurs after a while. I'm not sure where to go from here as far as dealing with this, and I'm wondering if maybe there is something I can do on the Kflop end to mitigate this?

Any ideas are greatly appreciated.

-Spank