The quality of the result depends on the instrument and the care with which the operator handles the procedure.

Many standard off-the-shelf gages no longer provide the right solution for today’s parts. That’s where custom gages come in.

Most of the time form measure-ment looks at basic geometrical shapes: how round something is, how straight or even how flat it is. You measure a cylinder and make a trace up the side to see if it’s straight; you take a polar trace to see if it’s round; you combine a number of these traces to see if it’s cylindrical.

Depth gages are among the simplest of gages, typically consisting of an indicating device mounted through a reference bar or plate.

A manufacturer of orthopedic implants needed to improve measurement and documentation proficiency of parts with literally hundreds of configurations. Air gaging was desired because it can quickly and accurately measure precision tapers.

Most gages on the shop floor provide a specified level of accuracy in conditions for which they were designed. But in the production environment, where tight tolerances are a way of life, it’s critical to think about gaging requirements before putting instruments out there and possibly having them not meet expectations.

The term “shaft measurement system” is standard industry parlance today, but to think of these gages as measuring only shafts is too limiting. For the most part, anything created as a turned part on a lathe is probably well suited for these devices. If there are features such as diameters, lengths, groove widths, fillet radii or chamfers on the part then it is well suited for measurement by a shaft measurement system.

A manufacturer of sub-surface oil well pump barrels needed a better way to check the inside of their barrels for wear. The barrels, some up to 30 feet long, must be periodically removed from the well and checked for excessive wear due to constant plunger motion.

Mahr is a specialist in production quality assurance for turbochargers. The tolerances of the various components of a turbocharger can be safely and accurately checked with Mahr’s measuring solutions.

Traditionally the length of a production run was a key factor in the selection of a dimensional gaging system. Typically, the higher the production run, the more cost effective a dedicated or customized gaging system was likely to be, while shorter runs would require greater flexibility and versatility in gaging. A dedicated gage would be faster, more accurate, and least subject to operator influence, but would also likely be more expensive.

It is perfectly natural that machinists should have an affinity for mechanical gages. To a machinist, the working of a mechanical gage is both straightforward and pleasing. Air gages, on the other hand, rely on the action of a fluid mate-rial, the dynamics of which are hard to (shall we say?) grasp.

These standards may have a significant impact on how some companies specify, measure and manufacture parts.