Index Homing odd offset

Hi,

I'm running ver 2.7.0 pre6 and I'm experiencing an odd offset after homing the Z on my lathe. The machine home has shifted by ~ 3/4"!
I tried to clear any G92 and I don't see any tool offset values in effect.
I'm still in the initial configuration stages and newbee, so I may be doing something wrong.

The Z home index routine worked initially. I have it setup to pull the Z towards a switch, backs off, looks for the index pulse, continues moving past that .025, stops and set machine home to Z0.

This routine changed after I had a joint following error when I was experimenting bumping up the feed in the ini file. I did not change any values in the homing routine.
Homing after the following error caused it to travel away from the index pulse by around 3/4".
I do know that the dro values changed. I jogged the axis when the drives were powered off, resulting in a positional difference that I was expecting to zero back out by homing.

Assuming the motor shaft, encoder and ballscrew alignment didn't change, what causes the machine zero to shift???
As a result, the soft limits are also off.

I need help restoring the original machine home. Thanks!

I assume that I'm reading in the index off my encoder on the servo. I can read in the signal, so I think that works. I'm not familiar with the software encoder counter.
Is there a setting in the ini file for that? In case I need to turn it off?
I have the ini file set under axis to HOME_USE_INDEX=YES. The search velocity is at .05, latch velocity at -.030 and final velocity at .030. HOME=0.0, HOME_OFFSET=0.02500
The index seems to trigger at the same spot each homing routine. It just no longer stops where it's supposed to.

I will check to see what the actual travel is to see if it's corresponding to any integer multiples of the motor revs.
If the index signal is not read in, is the motor supposed to stop turning after a few revs?

I wanted to keep the search velocity low as I was not certain what to expect on my initial setup. I may or may not bump it up. Thanks for the heads up.

I'm using the 7i85s and 5i25 from mesa to interface my encoders to linuxcnc.
What is the difference between software and hardware encoder counters? Sorry you got to dumb it down...

Just got back from the shop. I tried a few things and it looks like the homing routine just does not work properly.

The machine position values in the dro and position of the slide affects how the homing occurs. If let's say as an example the carriage is positioned at Z-2", and the dro shows Z-3" it will over run the home switch I assume by 1". It will trigger the home switch,reverse, reach the index, then reverse direction and move into my limit switch. It does not seem to zero out the dro.
If the value in the dro is closer to 0" and the position of the slide is -.1" off the home switch, the homing routine works. Carriage moves towards home switch, triggers, moves away from the switch, reads index and continues moving away in the same direction to the same location ~ .1" off the switch.
This seems correct and repeats.
The machine is trying to move to 0 based on the dro abs values regardless of the home/index signals.
Is this a bug?

The machine is creeping slowly towards the switch. I will confirm that I'm getting a clean index and home signal but I'm pretty sure it reads because there is a distinct change in velocity when the index is triggered and the index is always at the same point after hitting the home switch.
I will further reduce the speed to see if anything changes.

Okay, just looked at axis.2.index-enable (pins), z-index-enable(signals), hm2_5i25.0.encoder.02.index-enable(pins), all show a signal.

I can repeat the error. Another example is jogging the axis say into the middle of machine travel, click on home all, I then manually trigger the home switch with my finger, the axis will travel all the way back to the original z0. near the end of travel. I can watch the dro display rewind to 0. Instead of parking around .1" from receiving the signal which in this example would be somewhere in the middle of travel.

Is it dismissing the trigger or not setting the dro to 0 when it gets the signal?

Homing without index zeros the dro and works as expected.