Running servos in position mode instead of analog

Torque mode is harder than velocity to tune and in some cases requires two separate PID loops.
Never used DMM stuff, but from what i read online they are very good, so:
-are the motors mounted on the machine and how are they coupled?
-after mounting them in place, make sure they have at least space for +-5 revolutions forward and backward, meaning position them manually at the middle of the table
-use the DMM software to auto tune the drives, during this the motors will start to move slowly back and forth and the speed will gradually rise till it is tuned
-repeat that procedure for each axis
-set the drives to velocity mode, check if there are timings that affect the input lag, not sure how they are named in the DMM software
-only after all the above, set the drives to velocity mode and proceed to tuning in LinuxCNC.
Same applies for position mode, only tuning in LinuxCNC should be much easier in the position mode.

The servos are mounted to the machine and are coupled via htd8 20mm belts. Originally 40 to 40 but reduced that to 40 to 24(screw to motor) as I didn't need the extra speed. Motors are 1.3kw x/y and 1.8kw z which brings all the torque numbers to about double what the originals were. Also keeping the speeds to what the original machine was designed to so I am not trying to run a ballscrew or linear rail faster than it was designed.

Everything else you mentioned was done. Which basically means of the 5 parameters the drive has, 3 are turned off completely (torque filter, acceleration filter and integration gain). The remaining main gain and speed gain were adjusted with auto tune and then reverified with help from DMM tech support that they are correct. When asked about the 5ms delay DMM said it was because of the acceleration filter and advised to turn it off, which it already was. These settings also cause the drives to fault accelerating at 400ipm which is about 2/3 of rated speed.
One last thing I will be trying is running the motors under rs232 up to max speed, which I am sure they can do on there own since the drive will be using all of its filtering to create smooth motion.

Hey this is a bit alarming to read, I have had a projects in the works with dmm servos and Mesa analog control.... not running yet! Wondering if I should consider trying to sell these and buy another brand? What is known to work well in analog mode that doesn't break the bank?

From a personal standpoint I would like to see if yours have similar issues in speed mode as mine. I can walk you through the parameters and setup in the drives, got really good at that. The DMM manual has some typos and inconsistency, there are a couple settings that are easy to miss.

The bulk of problems revolved around the delayed response of the encoder feedback. I set them up in position mode open loop the other day and they work great and are accurate. Running a 6000lb vmc at 500ipm and an acceleration setting of 45ips/s. By Friday I should have them in position mode and closed loop with linuxcnc. See if the encoders still have delay.

As far as options I settled on yaskawa if I end up changing out from DMM. About $5000.... I have also heard good things about delta as well. I have used a Chinese servo as a spindle and that was no fun with little support.

In my research across many forums I didn't find any posts where someone had success with DMM in speed mode. I found a couple in torque mode but at least on I read had an encoder delay issue. Hope this helps.

Yea I have not powered the drives yet, but the motors are installed. I have an empty cabinet on my bridgeport boss, a couple dyn4 drives siting in there.

Mesa hardware never plugged into anything.....

I wonder how much of this I can return? Had it for a while but never used.

I won't have it operational for probably 6 moths, but I said the same thing this time last year. I've been designing and enclosure for the mill and until I finish that, and start fab I won't have the electronics mounted. Picked up a "working" chnc lathe a few weeks ago.... I have a thread in cnc machines section where I am troubleshooting poor servo performance and resolver issues.

Anyways I could probably wire up one servo on bench and configure my Mesa hardware to test this. My oscilloscope is old so it may be tricky to capture this delay and measure it... no recording or freezing a frame here.

Linuxcnc has a built in halscope that you can use to capture the inputs and outputs.

DMM customer service was very helpful but denied their drives could have a delay despite being shown the scope plot. They also allowed me to return a 1 year old motor in exchange for one with a brake.

I would set everything up on the bench and see if it works and how well. Shouldn't take much time.