Why Is CNC Precision Machining a Good Fit in Manufacturing?

Sep 17, 2023

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Much of the machining done in manufacturing today is accomplished on precision CNC machine tools. This precision machining usually involves the processes of turning, milling, or a combination of the two.

CNC precision machining involves shaping (metal removal) the raw material (workpiece) into a specific form with exacting dimensions and tolerances. Most, but not all, of these part shapes are derived from CAD (computer aided design) and CAM (computer aided machining) generated programs.

Creating CNC precision machined components relies on the use of high-level machining technology. Advanced computerized machine tools are required to achieve tight tolerances and create complex geometric shapes. The parts require a high degree of repeatability and accuracy. This is achieved through the use of automated computer numerical control (CNC) machine tools.

The marketplace for almost all products is driven by product improvement. A constant scrutiny of the end product determines its value in the market. This value-driven process can make CNC precision components very competitive.

With every technical advancement and introduction of new products, be it aerospace, electrical, automotive, industrial, or medical, there is a need and demand for improved parts. The component improvement process results in greater efficiencies and reliability of the end product.

CNC precision machining is capable of delivering very tight tolerance parts, typically ranging from ±0.0002" (±0.00508 mm) to ±0.0005" (±0.0127 mm), with a high degree of part complexity. In addition to providing tight repeatable tolerances, exceptionally smooth surface finishes can be achieved. Much of the accuracies and finer surface finishes are achieved because of the advances made in servo control technology.

Precision CNC machine tool accuracy is measured against how precisely its axes can follow intended tool paths to commanded end points while under load. Repeatability is measured by how precisely it can duplicate commanded motions.

Thanks to the advances in faster processors coupled with the latest generations of servo technologies, greater CNC precision can be achieved. As a point of reference, a modern CNC lathe has a positioning accuracy of 0.0004" (0.010mm) and repeatability of 0.00008" (0.002mm).

Being able to produce highly accurate CNC precision parts means a reduction in waste. This, in turn, helps reduce production costs.

The very design of precision CNC machines lends itself to modern manufacturing. Today is an age of "custom" production. In the past, much of manufacturing was driven by high production, with little emphasis on customizing the end product. In contrast, much of today's production is geared toward a higher level of customization.

This manufacturing philosophy requires a high degree of flexibility. Precision CNC equipment is designed for higher repeatable precision, shorter setups, shorter lead times, lower inventories, and less elaborate fixturing. This type of equipment is used in the manufacturing of components for almost all modern markets. It is also well suited for the adaptation of automation for higher-level production.

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