Precision machining is the process of creating intricate and precise parts, components and objects that are used in our everyday lives. Precision machining creates parts according to tight tolerances so that they fit specifically and precisely into the object or machine they are made for. Because precision machining needs to be so accurate, the materials and machining equipment used for precision machining must be very specific. Here we look at some of the most common machining equipment used in precision engineering.
OVERVIEW OF PRECISION MACHINING TASKS
In general terms, precision machining tasks can be divided into milling, turning and boring. Precision machinery focuses on creating a part or object by subtracting material, as opposed to adding material to create the right shape. In some cases, cutting machinery is also included under precision engineering.
Milling processes involve using cutting and grinding tools to remove material to create a part. Turning machines rotate the material and use cutting tools to shape and modify the part. Boring machinery functions by drilling holes in the material using precise rotating cutting tools. The following precision machining tools each fit into one of the above categories.
Swiss machines provide accurate and precise function according to specific instruction encoded by CNC (computer numerical control). Swiss machines were originally used to create parts for Swiss watches and can compose tiny components from just 0.75 inches in diameter. Swiss machines are very effective at machining small parts and long, slender parts without causing displacement or vibration. The Swiss machine provides control by holding the workpiece in place, while the tool rotates around it. Swiss machines can also be modified to accurately shape and compose your unique part. Swiss machines can process on 7-axis, up to 9-axis for more complex and intricate parts.
Lathes are a precision machining tool that rotates the workpiece against a cutting tool. Lathes can also be controlled by a computer that allows for intricate designs to be created from Computer Numerical Control. In most precision machining workshops, lathes can have varying capabilities with up to 5 axis machining, producing parts with diameters from 0.062 to 22.00 inches. Lathes can often be customized to provide varied functions according to your specific needs. With the assistance of Computer Aided Manufacturing, design files can be directly imported to the lathe function to more accurately and quickly manufacture the parts.
Milling machines can be vertical or horizontal, depending on the spindle, and are generally used to cut, shape and grind materials to size. In a milling machine, both the workpiece and the tool may move to create the shape and dimensions that are required. Because heat and friction can be generated in the functioning of a precision milling machine, cutting fluids, lubricant and coolant may be used to generate the most precise and even machining. Spindle chillers may also be used to help maintain machine accuracy despite temperature fluctuations or heat generation.
ELECTRICAL DISCHARGE MACHINES
Electrical Discharge Machines (EDM) is used to cut metals that are electrically conductive. The EDM machine uses an electrically charged wire or electrode to cut or punch the metal. There are two main EDM machine types – wire electrical discharge machining and sinker electrical discharge machining. The wire EDM machine uses a wire to cut through metal to obtain the desired shape. In sinker EDM machining, a power supply produces a spark between the electrode and the metal, which cuts the metal. Electrodes can be designed and manufactured in house by precision machining companies to achieve the precise requirements needed.
Laser engraving is another way to make precise marks and cuts on metal for precision machining. A laser is installed on a rotary attachment, which allows flexible functionality for etching or engraving a part. Laser engraving may be used for aluminum or plastics and can be used to make marks on medical tools. Laser engraving can also add an essential aspect to precision engineering by allowing custom logos, serialization, and QR codes to be imprinted on parts or products.
While many tools may be used by precision machining companies to produce precise and accurate parts, the list above includes some of the precision machining equipment most commonly used by precision machining companies.