HBM has launched a hole-drilling
rosette to increase the accuracy of
residual stress measurement. The
new RY61M SG has a patented
structure that uses six measuring
grids to determine the eccentricity of
a hole, a potential source of error.

Measuring grids are arranged
around the drill hole, with each of
the opposite SG pairs being interconnected
so that their signals are
averaged.Measurement error from
drill-hole eccentricity is said to be
reduced by a factor of five because
HBM uses six measuring grids. RY61M
SG is easily connected; grids are
already connected on the carrier foil,
or on a small PCB.