Most premium cutting tools need to be ground within a tolerance of about five microns. And sometimes even more precisely than this. But how tight is this tolerance in reality?

A micron (μm) is a unit of length equivalent to one-millionth of a meter. For comparison: a single human hair has a diameter of 80 μm and a bacterium is about 3 μm in size.

A micron could be described as “impossibly small”. But machine operators achieve the impossible every day and produce tools and parts with a tolerance of only one or two microns.

Tolerance is the deviation allowed in the dimensional accuracy of a workpiece. Industries such as aerospace demand consistent, uniform parts with very tight tolerances. This is because the parts have to function under extreme conditions. Aircraft parts have to withstand speeds of up to 1000 kilometers per hour. Jets can even reach speeds of over 2000 kilometers per hour. In space travel, the parts must survive re-entry into the earth’s atmosphere and still function properly at temperatures of 3000 degrees Celsius. Here, perfect interaction with the surrounding parts is essential. Aerospace, military, and other industries that install components for use in extreme conditions must consider the cost of reliability and durability. They can only accept perfect parts.

Machinists and grinding specialists thus need the right tools, skills, and machines to supply these industries. This is also an economic factor because imprecise grinding processes lead to scrapped parts.

When grinding shank tools, it is important to minimize the runout – i.e. the deviation of one or more reference features from another reference point when the workpiece is rotated 360° around the reference axis. Put simply, good runout (in this case, runout means concentricity) means that the workpiece exhibits minimal or no “swash” when rotated around a single point. The main cause of poor runout? An improperly set up and maintained workpiece holder. This also leads to higher scrap rates, which leads to dissatisfied customers and monetary losses for the company. In contrast, high-precision chucks keep the tools very straight and ensure excellent concentricity, usually with an accuracy of just a few microns.

In aerospace and other demanding industries, a single micron sometimes decides whether a part can be used or will end up as scrap. High-quality precision grinding machines can achieve microscopic tolerances and help manufacturers meet high customer requirements down to the μm.

As a manufacturer of MÄGERLE, BLOHM, JUNG, STUDER, SCHAUDT, MIKROSA, WALTER, and EWAG machines, UNITED GRINDING machines help you to process parts with micron precision.

We are always glad to answer your questions. Contact us