Issues after calibration, CMM locked up?

[[Ja...]]

Well it's definitely going to be a Monday here ...

Last week we had a Zeiss tech in to perform a standard calibration on one of our machines, Duramax with an XXT head. When I came in the morning after calibration was completed to reset up our CMM table, position the stylus holders and reference sphere, and run some qualifying programs, I ran into significant issues.

The CMM seems to boot up as normal but when it goes to its homing position (appears to be exactly where it usually goes) it then locks up. I am unable to use the joysticks to manually move it, it beeps and the error light goes off at the end of homing and a small icon blinks on the controller screen (see attached) that means there is a collision between the stylus shaft and the workpiece but it is up in the homing position not near anything and the stoplight stays green, so it is not acting like there is a typical collision. It does not have the error beep or collision icon if I move the joysticks in the Z- or Y+ position but will not move at all regardless of which directions I try to move it.

I have tried restarting everything multiple times and turning the drives on/off with no success.

Unfortunately since I can’t manually move the CMM I cannot define the stylus system holder locations or the reference sphere location so I am unable to run qualifying programs to even begin to get the machine set back up. We had no issues prior to calibration, something had to have been done or left undone by the tech.

I have opened a support ticket with Zeiss to begin working through whatever this is but was curious if any of you have seen something similar after calibration?

Jogbox Error Icon.jpg

[[No...]]

Not after calibration and no collision icon on the display, but when our O-Inspect is too close to the homing point when homing, it also locks up (i.e. hits the mechanical end stop and refuses to move). I have no idea if this is even remotely similar to what you experience, as I never had a Duramax. Can you move (push/pull) the axes manually when the drives are off?

[[Ja...]]

Thanks for your reply Norbert.

I am able to move the head around when the drives are off by gently pulling in different directions but after doing so when I try to turn the drives back on I am still unable to move it with the joysticks, get the same beeps, error light, and collision icon.

On a hunch I went into the CMM settings and for some reason the homing position was set X 30.00mm / Y -30.00mm / Z -30.00mm, which seemed weird so I reset those values to 0.00 mm, saved, rebooted, and it seems to go the the new homing position without issue at startup and I have control of the joysticks again.

No idea where those weird homing values came from but I appear to be up and running again, going to get everything set back up and before I get too excited though.

Update: I was able to locate and run my qualifications, so it looks like that issue is resolved. I did restart everything and it did a homing crash one more time and the CMM didn't register that it had a stylus loaded initially but I manually added it, did another restart and everything seems to work. Super weird, no idea how this happened but glad to be back up and running.

[[No...]]

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Those are the standard homing values for portal CMMs. Maybe the tech changed them out of habit.
But out of curiosity: Why does the Duramax malfunction with the above values? Is one of the axes reversed?

[[Ke...]]

The values entered there are not for where the machine homes(reference might be a better term than home, honestly), but for where the machine moves after it finishes homing. Generally speaking you do not want to leave them at 0 in any axis, as that can cause issues due to the true Home being at the end limits of the machine, so not moving off home at all can cause the CMM to have End Limit errors. Typically I go with at least 15,-15,-15(mm). Were it me, I would try removing the probe from the probe head and rehoming the machine, to see if there is an error, then repeating the homing after reinserting the probe to see if the error reoccurs.

Norbert,
To the best of my knowledge all Zeiss CMM's use the same axis direction, and I can say with certainty that the Duramax is not reversed

[[No...]]

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That's why I was asking, because that was my impression too. Even the O-Inspect 322, whose table moves physically in the opposite direction in X and Y, is consistent from the viewpoint of the camera. Of course I know that the above values are just the clearance offfsets, but that's the very reason I don't understand why smaller values should make a difference.

[[Ja...]]

Update: The weirdness continues ...

So while my workaround of changing the homing position to zeroes kind of works (it some times takes a several times powering everything down and starting back up and manually inserting the master probe into the XXT head, as it doesn't want to recognize other stylus systems at start up, until I can successfully run a qualification program) after running a diagnostic program that Zeiss tech support sent over and returning the results (no idea what they were) they are now sending another tech out for an onsite visit later this week.

I hope to get whatever is going on resolved at that time. I have had some other issues post-calibration such as file paths being incorrect causing any programs I set up for saving results, which I then typically transfer over to Excel spreadsheets, to "red light" at the end of their run with a pop-up stating "unable to delete directory" that I have not been able to resolve.

Again, prior to the calibration a couple of weeks ago everything was appearing to run smoothly and I had no issues with this CMM, this has been a frustrating head scratcher and I can only think that something happened during calibration.

[[Ja...]]

Final update on this issue, hopefully resolved.

Zeiss service tech was in last week, spent a lot of time in what looked like going over what the previous calibration tech did or didn't do and came up with two things that were contributing to the CMM "crashing" during homing.

The first is a classic case of grease getting on the glass scale, something I probably should have been able to figure it out but I missed a glob of grease at the very extreme end of the scale when I was troubleshooting. Last week's tech said there was an abundance of grease used in the last calibration and it splattered a bit more than he liked to see. So I guess REALLY clean your scales, kids!

The other is one I would not have been able to catch or correct, the calibration tech apparently updated the firmware on our controller to a newer version than what is recommended for our current setup causing intermittent communication issues. So that is fixed now too.

I am still having some weird file path issues when I try to save my actuals to a desktop folder to later transfer to our Excel inspection sheets, and issue I did not have prior to calibration, but that was out of the scope of the tech that was working on our CMM last week and something that I will sort of deal with the hassle of for a bit until I have a chance to call into Zeiss and get someone with a bit more knowledge on that.

Thankfully the CMM is fully operational otherwise, it was going to be a huge deal if we didn't have it up and running the beginning of next month as I'm diving into a government first article.