Even with the numerous new and emerging manufacturing techniques on offer, nothing beats the Computer Numerical Controlled (CNC) machining's reliability and efficiency. Every day, machine shops throughout the country produce millions of precision parts in different substrates using one or more of the available CNC machining techniques.
CNC processes are used in a broad range of applications across a spectrum of industries, including industrial, medical, aerospace, oil and gas, firearms, hydraulics, etc. Manufacturers use a variety of materials, including metal, plastics, composites, glass, and wood. Here is a look at the five most common precision CNC machining techniques you can utilize to make high-quality rapid prototypes and production parts.
1: CNC Lathes & Turning Machines
With CNC lathes & turning machines, the materials are turned or rotated during the machining process. Typically, the cutting tools are inserted in a linear motion along the spinning bar stock, extracting material around the circumference until the required diameter and feature are achieved.
A subset of CNC lathes is CNC Swiss lathes that allow the bar of material to rotate and slide axially through a guide bushing(referred to as a holding mechanism) into the machine. As a result, the material gets much better support as the tool machines the part features, providing better, tighter tolerances.
CNC lathes and turning machines often create internal and external features on the part, such as drilled holes, bores, reamed holes, broaches, slots, threads, tapping, and tapers. Common components made on CNC lathes and turning machines include screws, shafts, bolts, poppets, etc.
2: CNC Electrical Discharge Machines(EDM)
CNC EDM (electric discharge machine) uses highly controlled electrical sparks to mold materials into the desired shape. Also known as spark eroding, spark machining, or wire burning, or die sinking, this technique involves placing a component under the electrode wire and programming the machine to emit an electrical discharge from the wire. This produces intense heat (as much as 21,000 degrees Fahrenheit), causing the material to melt or flush away with liquid to produce the desired shape or feature.
EDM is more often used for generating precise micro slots, holes, angled or tapered features, and a variety of complicated features in a component or workpiece. It is appropriate for tough metals that would be hard to machine to the required shape or feature.
3: CNC Plasma Cutting Machines
Although CNC plasma-cutting machines are similarly used to cut materials, they accomplish this operation through high-powered plasma (also known as electronically-ionized gas) torch controlled by a computer. Like a gas-powered torch utilized in welding, plasma torches accomplish up to about 50,000 degrees Fahrenheit. Typically, the plasma torch melts through the component to create a cut in the material. The materials used in plasma cutting machines must be electrically conductive, such as steel, stainless steel, brass, aluminum, and copper.
4: CNC Milling Machines
CNC milling machines are designed to rotate cutting tools while keeping the workpiece or block stationary. These machines can produce different shapes, including face-milled features (flat, shallow surfaces or cavities on the workpiece), as well as peripheral milled features(such as deep cavities, slots, or threads). More often, components produced on CNC milling machines are square or rectangular with a variety of intricate features.
5: CNC Laser Machines
CNC laser machines feature a pointed router with a precisely focused laser beam used to cut, slice, or engrave various materials. Typically, the laser heats up the material and causes it to vaporize or melt, creating a precise cut in the component. The material is usually in a sheet format, and the laser beam hovers back and forth over it to make an accurate cut.
CNC laser engravers are mainly used for part marking or decoration of already machined components. It allows you to easily engrave a logo and company name into your CNC milled or CNC turned component.
Overall, precision CNC machining provides abroad range of production capabilities for parts and finishing in various industries, including manufacturing. Depending on the application environment, needed material, volume, lead time, budget, and desired features, there is always an optimum method that will deliver the desired result. Please don't hesitate to contact us if you have questions about what CNC machining method will best suit your desired features. Our team will be more than glad to review your print and provide timely feedback and input on the specific elements in your design.