**RESOLVED** Z axis oscillation

[BeckettAir]

My Z axis encoder is a Acu-Rite II. I used the line driver chip to obtain the differential output.
I get no errors and the ABS counts up in the ccw direction and the DRO is reading correctly.

If I jog the Z the axis it will start to oscillate up and down about 1" with the Kd set at default (3.00)
Ive raised it slowly all the way to 10.0 but this only reduces the travel and increases the speed of the oscillation untill it is just a up and down vibration but does not eliminate it.

Any help would be great, Thanks Jeff

[cncsnw]

You might try cutting back on Ki (maybe in half or less).

Do you also have a rotary encoder on the motor that you could use, or do you only have the linear scale?

[BeckettAir]

You might try cutting back on Ki (maybe in half or less).

Do you also have a rotary encoder on the motor that you could use, or do you only have the linear scale?

I have a rotory I could install on the motor but I want to be able to read the DRO if The handle is used, and I dont want to have to keep the spindle locked in to the drive for manual milling.

I will try your Ki suggestion thxs.

[BeckettAir]

Ive slowly reduced Ki from .004 to .001, this helps some but the axis is still moving very fast like a pulsation.
Im also getting some heat from the motor.

Is there any documentation on how to tune the motors?

[BeckettAir]

I found this tuning guide Al posted.

Working pretty good after some tuning.

[cncsnw]

What did you end up at with Kp, Ki and Kd?

[BeckettAir]

What did you end up at with Kp, Ki and Kd?

here is what I ended up with for my axis's

X - Kp =.5 Ki=.004 Kd=2.2

Y - Kp=.5 Ki= .004 Kd=2.5

Z - Kp=.3 Ki= .00005 Kd= 2.3