[JFritts]

Help!

I purchased a used VM17 and when the machine turns on, after the homing sequence, I go to do a tool change and the spindle height to match the carousel is off. It can be from a 1/4" to 3/4" high or low.

I then have to go into F7 Parameters..... F4 Axis.... To "Tool Change" and adjust the Z# to move the spindle to the correct height. Anyone know of another setting in the machine I'm unaware of needing to be set to avoid this?

The indicators for the Z limit switch shows it works. The value for Z is different after every homing cycle.

In the words of Slim Pickens in Blazing Saddles, "I am deepressed..." Help!

[allen mullis]

One of two things is going on, either your z home switch is on the verge of not making, or the z drive has been changed and someone didn't widen the marker pulse width in the drive. Check the pitch of your z screw, and make marks at where it happens to find it's home on the column, see if the marks aren't a consistent distance apart. consistent such as the same as one revolution of the screw, or sometimes two or three.

[JFritts]

One of two things is going on, either your z home switch is on the verge of not making, or the z drive has been changed and someone didn't widen the marker pulse width in the drive. Check the pitch of your z screw, and make marks at where it happens to find it's home on the column, see if the marks aren't a consistent distance apart. consistent such as the same as one revolution of the screw, or sometimes two or three.

Thanks Allen!
I'll put it through testing Monday and see what transpires.

[ZZZZ]

Also, check the home switch itself. Make sure it is not sticky with built-up gunk or clogged with chips. When the switch re-opens will affect the location when the axis makes the last change-of-direction to look for the marker pulse on the encoder.A sticky switch may not release reliably.
During the Home Sequence, you want the last move the motor makes to be a half of a turn, as close as you can reasonably get, to give you the best chance of finding the marker at the same place in the travel.

[cgmaster]

I was having the same problem as well as homing issues turned out the drive was changed and marker pulse was not set correctly. I went through everything for over a year trying too figure it out.