Bridgeport EZ Trak axis problems

[ZootCapri101]

Have a couple year old EZ Trak vert. mill and have a problem that I can't diagnosis. Operator fouled part while using the manual pulse coder on the operator's panel. When moving X of Y it would be unstable and inconsistent in the direction of requested movement. When you would change directions using the manual knob if would actually jump the table about 1/2". Y axis was the worst. No faults in drives or op. screen.
I suspected the pot itself seeing it is common to both axis and the machine homes out fine and would go + - in the jog mode with no trouble. Installed new pot, no help. Read the manual and these signals go through the BMDC pcb, swapped with another working mill, no help. Rang out all wiring, connectors, I/O pcb to no avail. Successfully downloaded the original operating system thinking something might of gotten corrupt, no help. Even swapped out another servo drive and the problem is still there.
Sad to say, I am now getting a DAC underflow and overflow alarm now when I move Y axiz at any decent feed rate now. Not sure if its something I've induced or is this the original problem getting worse.
Not sure where to go from here. Thank God the mills not needed now or this would a real nail biter. Thought of tuning the drives, but the
problem was there with a subsitute, and its something that effects both axis.
Anyone got a thought out there? Thanks

[machintek]

You may need a 15 second repair.
At the main screen, press the * key.
A box should pop up asking for a code.
code is 11235
followed by ENTER twice.
Check your machine parameters that pop up.
Machine series, amount of travel, etc.

Pay attention to the backlash and pitch error comp values. I believe that is why the table is jumping when you reverse direction.

George

[ZootCapri101]

George, Thanks for the help. Couple of the parameters were waaay off, measured backlash error, input figures and the mills smooth and responsive. Have no idea how these #s were ever entered and how it ever ran with them.

Thanks, Dan

[machintek]

What version of software are you running?
Version 7 if shut down in metric will boot up in inch but the machine parameters will still be in metric. Messy.

George