Bilateral Comparison of a 420mm x 420mm CMM ball plate.

Final Report, 5 Oct 2004



The main purpose of this bilateral comparison was to aid the development of an artifact calibration service for CMM at NML Ireland.

During the visit by Jim O’Donnell and Paul Turner from the NML-Enterprise Ireland to Gum-Poland, the calibration of the NML ball plate was demonstrated by GUM. Values obtained from this calibration were compared to measurements made on the ball plate before going to GUM and also on return to Ireland.

The exchange of information on the development of an uncertainty budget for ball plate and other artifact calibration was discussed.

On return to Ireland the calibration of the ball plate was repeated and uncertainty budget determined. During this work contact was maintained with GUM.







GUM to demonstrate the calibration of a 420mm x 420mm ‘ball plate’ to Enterprise Ireland staff. On return to Ireland, the ball plate will be recalibrated in Enterprise Ireland and an evaluation of the results carried out.

Exchange of experience on procedures and methodology in the use of ‘ball plates’.

Exchange of technical information on ‘ball plate’ calibration software.


Length (L)
Howard McQuoid, NSAI NML (Ireland)
Phone: +353 1 808 2609
Fax: +353 1 808 2026
Coordinating Institute
NSAI NML (Ireland)
Participating Partners
GUM (Poland)