CMM Probe Calibration

[R. C. Hinds]

Hello all.

 

We have a Ziess CMM. The probes are calibrated every morning, thus the device is unavailable for a good hour of production time. There is some disagreement as to whether daily calibration is necessary. What do you folks do? Calibrate daily or...

 

MCAM X6 MU1

Solids,Port Expert, Multi Axis, etc., etc.

[Pilot Plant Supervisor]

We do a re-qual on a fixed sphere and run a quick check program on a standard. The standard is a 2" and a 3" gage block set at angles in a fixture. If the machine measures the blocks within .0002 of nominal, we are good to go. The inspection report is filed and copies are included with part certification. The whole process, if everything measures out good, takes about 10 minutes.

[kh012]

We calibrate all the probes at all orientations biweekly, but our cmm is in a climate controled room

that stays at 68 deg. The cal. takes about 2 hours to run. We will cal. more often if needed ie. dirty

probe or inconcistant results.

If you don't have a stable temp. or are probing dirty parts then you may want to do it more often,

but usually just a quick cal. on the first or primary probe in the morning will be ok.

 

HTH Ken,

[Brad St.]

What requirements are you looking to meet? are you looking to simply verify the interim measurements then you could possibly do an interim artifact check at various times to prove validity of your measurements instead of a full calibration.

 

That brings you back to is the artifact checks equal to the measurements you are taking or needing?

 

What process and control are you going to use for the artifacts?

 

You could ideally run them as a sub program if conditions are ideal in your setups also with if then statements or scripting to generate the reporting you would like for your process.

[Joe788]

I calibrate the probe whenever I get readings I don't like.

 

I've never run a Zeiss machine, but with PC-DMIS, I'll just calibrate the locations that we're going to use. Obviously, this won't work for you if you use a brazillion orientations every day - but for us, it's a 10 minute process or so.

[R. C. Hinds]

Thanks to all of you. By the way, it is usually the CMM that gives us dimensions that one does not like.