In this article, I wanted to go beyond the simple go/no go measurements that most air gaging is used for. Air gaging is a highly effective and efficient way for measuring these simple diameter requirements. It is also extremely repeatable on tight tolerances, but for this article, I wanted to focus on using air gaging to measure form requirements such as roundness, flatness, perpendicularity/squareness, taper, straightness, matching, and others. 

Recently, an automotive parts manufacturer was searching for a system to measure over 4,000 individually machined components a day. 

Screw thread inserts (STI) require the threaded hole to be inspected prior to inserting the threaded insert or coil. The dimensions and tolerances for the gages used to inspect these threads have been a bit confusing over the past 30 years. 

The first time it happened was in 2009. I was about to take the helm of a 34-foot catamaran in the British Virgin Islands as captain, my baptism into the world of “bareboat” sailing. “You’re good to go,” said the dockhand. 

This is an area of gage making that takes something simple like a go/nogo plain plug gage and adds another feature for another check, such as hole depth.

Quality control measurement continues to evolve, especially as coordinate measuring machines (CMMs), 3-D measurement tools and other inspection innovations gain popularity.