From Ken Lawrence:
Last year Sonic Imagery Labs introduced the Precision U.S. Specialty
Multi-Gauge, which has become a standard product. Its theoretical accuracy
is about equal to the Linn's Multi-Gauge, but unlike the Linn's and BSG
gauges, the image is not printed on the bottom, and its film is thicker
than both of those, so it can introduce a parallax problem in reading the
measurement. Also, its long-term dimensional stability is unknown.
From Richard Doporto:
The Rev 3 Sonic Imagery Labs Precision Multi-Gauge combined the
Specialist style perf gauge, added and analog style gauge, grill gauge and
7 other tools in one device. Several years was spend researching
technologies for manufacturing this Gauge as we wanted to make a
technology leap instead of making a variation on existing products and
technologies. The technology finally chosen is based on Credit Card
Manufacturing ANSI Standard X4.13-1983. This standard resolves many if not
all technical issues that Ken Lawrence mentions ... In a nutshell, the Rev
3 and the current Rev 4 Gauges are a triple laminate composite. The image
is on the top of the lower third layer. The composite molecular grain
layers are opposing to limit or cancel thermal expansion effects (per ANSI
standard mention above) and to eliminate the image from scratching off. In
response to Ken's comment on Parallax, which is a very valid one. The
image in the Gauge is .004 inches above the stamp to be measured if the
stamp is under the Gauge. In this case the Parallax error is a fraction of
a percent.
