Hi Tom,

I've been reading up a bit on Kflop, looks interesting if challenging but a solid contender to put on my CNC router, currently controlled by WINCNC.

I've not been too happy with Win CNC / my router recently, although the problems that make me unhappy may only be marginally related to wincnc itself, other areas could be the machine's aging mechanics and possibly poorly tuning of servos.

The machine is a 2001-2002 CNT motion systems and uses a win-cnc control and technic servo drives and motors, AC I believe, with step and direction drivers. It started out as a dos machine and has always been a little less than desirable in it's accuracy and smoothness of cut, though a 14 year workhorse despite all that. I have a smaller techno-isel that I always used for more precise parts.

The problem I had is that the drives are mounted on the machine gantry back, and if a power wire has a intermittently broken connection, as my spindle fan did, it sent spurious step signals to the drives before the loop was closed. Thus, my "closed loop" system was loosing position and squareness until it torqued out and the drive faulted. Very hard to troubleshoot, but once I did so, I realized ANY setup similar could have the same weakness. Drives in the cabinet and proper wired and shielded is a different matter but to get there, that's pretty much a total rebuild anyways, new cabinet, new cables and everything moved over. And, even then, I don't think I could close the loop to wincnc anyways.

So, looking at my options, all kinds of options, I came across Kflop. Closing the loop back to the control sounds great, but I'm unsure of how it would work with the step and direction drives that are so common now. I assume those drives *need* the feedback loop internal or else they will fault (or runaway maybe too). So, I am wondering how exactly a setup would look like if I was closing the loop to both the drive and the kflop board (or daughter board if needed for the type of encoder I have). Would I simply put wires from the drive back to kflop, so the signal went to the drive but continued on to kflop......if kflop detected an movement error it could send a few extra step commands to get the motor back on track? Or, would I have to run two sets of wires from the encoder?

Would I use Kmotion to tune the servo driver, or set the driver to basically allow kflop / kmotion to handle the tuning aspects?

I have not searched thoroughly other threads for this issue, save for some on Gecko 320s that are a similar closed-loop in the driver setup, so my apologies if this has been covered elsewhere. Having had this uncommon problem, I'd like to be able to solve it 100%

Thanks, Greg