International comparison of high-accuracy roundness measurements – M. Frennberg and A. Sacconi

Abstract.

An international comparison of roundness measurements at the highest level of accuracy has been
carried out between eight European laboratories. Three roundness standards with different designs and roundness
deviations were measured. One standard was a commercially available type, two standards were developed for the
purpose of this comparison. The agreement between the laboratories was within +/-20nm for the standard with the
smallest roundness deviation. The comparison was sponsored by the Commission of the European Communities.