Hello ,

We received a brand new UMC 500 SS 10 days ago.
First look very good , very powerful machine B and C axis had probably 0,001 deg backlash. I didn't expected such accurate rotaries, probably because of the scales.
After working on the machine a few days I noticed unrepeatable tool offsets. And I mean by 0.05mm up and down during the day. For me this is huge number.
I spoke a few days with the technicians to try to figure out the problem but all the variable we could imagine were not the cause of this problem.
I did a special warm up cycle routine, my factory is climate controlled so the temperature variance is not the problem.
Between a cold and warmed up spindle the difference is about 0,01mm which for this kind of machine I think is acceptable.
MRZP calibration was done several times - major differences in Z , very small in x-y.

We made a 50cm concrete foundation especially for the machine about 2 months before arrival. ( plenty time to cure ).
The machine is not anchored.

After a week of headbanging I understood that another local customer who received the same machine in the same shipment has the same issues ....
Now we wait a response between HAAS and our HFO.

The only thing we could think about is a mechanical or software issue... Backlash in Z is bellow 5 microns. X-Y have a little bit bigger backlash but bushing bores I interpolated were spot ON.
So mechanics seems to be fine.

Any other UMC owners with same issue ?