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What is a CMM machine?

A coordinate measuring machine or CMM is a device that is used to manually measure 3D coordinates of a surface with a lot of accuracy. It is also used for inspecting surfaces to verify geometry, and to measure any deviations from nominal specifications. There are two main types of coordinate measuring machines, the Optical CMM and the Contact CMM. Contact CMMs are machine tools that are specially designed for measuring a workpiece on the machine's table, which has a precision surface. Optical CMMs are not actually machines, but they do measure 3D coordinates. They are computer-controlled and programmable optical instruments that measure the 3D coordinates of a surface by taking a picture of the surface and running the image through a program that analyzes the coordinates. There are three types of Optical CMMs, the Laser Tracker, the 2D Scanner, and the 3D Scanner. The Laser Tracker is a type of Optical CMM that is used for measuring parts that are stationary. The 2D Scanner is a type of Optical CMM that is used for measuring parts that have moving parts. The 3D Scanner is a type of Optical CMM that is used for measuring parts in a non-contact manner.

Contact CMMs are the most accurate of the two types of CMMs. They are designed to measure a workpiece on the machine's table, which is called a "nominal surface." A contact CMM is most accurate when it is measuring a workpiece that is on the surface of the machine's table, so it is not possible to measure a workpiece that is not on a surface. Contact CMMs are not usually used for measuring parts that are too large to fit on the machine's table. Contact CMMs use a probe that is moved in a variety of patterns and measurements are taken very accurately. Optical CMM use a laser or a probe to measure the 3D coordinates of a workpiece. The probe is usually mounted on the CMM's table, which is called a "nominal surface." The probe is usually mounted on the CMM's table, which is called a "nominal surface." This means that the probe is usually not able to measure a workpiece that is not on a surface.

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