Master CMM Sphere

[[Sc...]]

I could not find my original post which I believed it was on old Zeiss metrology forum platform.

What is the best practice? Should master sphere be send off to 3rd party for calibration every x years or never send it out?

As I recall from old post that some users won't send it out because it was already certified by Zeiss. Zeiss calibration technician always ask me for the sphere, so they calibrate their stylus and use "Black Book" for certification data.

The real issue I am having is the 3rd party calibration turnaround is about 6 MONTHS! I must have the sphere at all times especially stylus configuration and probe replacement. I am trying to tell my company not to send the sphere out.

Your input would be greatly appreciated.

[[Wo...]]

I never send the spheres out for calibration, but if you absolutely need to, I would just get a second sphere and rotate them - when one is out for calibration use the spare on the machine and when the original comes back send out the spare for calibration and so on.

As far as I know the stylus calibration is based on the Masterprobe, so you can have multiple spheres and one Masterprobe.
I use different diameter spheres all the time and as long as they are referenced with the same Masterprobe everything should work.
The only thing I've never got a straight answer for is the "Update Stylus data" setting in reference sphere management.

I've never had a question about reference sphere calibration during an audit, but we're just basic ISO9001 shop so that doesn't mean much. I bet with the more stringent standards the auditors are more inquisitive.

Thanks,
Wojciech

[[Je...]]

ZEISS no longer offers recertification of REF spheres due to the cost benefit for our customers. It is cheaper and easier for our customers to purchase new. I can't speak to any additional reasoning but that in itself is usually enough justification to the accountants and engineers.

Cost of 3rd party certification meets or, more often, exceeds that of a brand new sphere. Lead times are quite excessive. If you require a certification on your REF sphere at specified intervals for your Quality standards, we typically advise purchase of a new REF sphere and updating serial number records rather than attempting recertification of existing through a DakkS/NIST certified company.

New REF spheres are available as in-stock items in the Webshop