Thickness is one of the most frequently measured dimensions, and one that’s very easy to understand. So, you might think that someone would come up with a one-style-fits-all measurement approach that’s good for just about every kind of thickness application. But it just isn’t so.

There are many approaches to measuring thickness, depending on the requirements of the part. Some of the most common include micrometers, thickness gauges, air thickness gauges, and motorized gauges with many variations of each. They range in price and complexity from a few hundred dollars for a standard handheld tool to a few thousand dollars for ones that are custom-built for the application. One important consideration that makes each of these solutions different from the others is the way the gauge makes contact with the part.

Whether it’s the thickness of a piece of sheet metal, a silicon wafer, a latex glove, or photographic film, we’re usually talking about measuring the distance between two parallel surfaces. Accurately determining the length of a line that is perpendicular to two parallel surfaces has everything to do with how the gauge makes contact with the part.

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