Precision metal fabrication can use many different types of manufacturing procedures. Let’s take a look at the benefits and drawbacks of three different precision metal fabrication processes.

Electrical-Discharge Machining

Electrical-Discharge machining uses an electric spark to remove metal. The electrical arc is used to precisely erode the substance of the metal. This eliminates the need to exert force on the sheet metal during the intricate manipulations required to produce most precision metal products. Commonly used EDM machines are the plunge and the wire-cut types.

Wire cutting EDM is a very accurate and flexible form of precision metal fabrication. An electrically charged wire is passed vertically though the metal material at a variety if angles, resulting in very precise and complex geometric shapes. Wire EDM is often used in conjunction with a CNC machine to improve accuracy and increase ease of production. An operator can change the gauge of the wire used to create even smaller and more complex patterns when necessary. The process is slow when compared to other precision metal fabrication types.

EDM is not cost effective for mass production of dies and molds. It is however, a very affordable option for short run production and start up projects.

High Speed CNC Milling

High speed CNC milling is another popular precision metal fabrication process. This process uses spindles rotating at high rpm to bore into the metal, creating the desired pattern. With many machines, Speeds can reach up to 40,000 rpm and computer guidance produces an accuracy of to ±0.0002. Very complex patterns require frequent chancing of spindles and recalibration of the machine. This makes high speed CNC milling an unlikely choice for very intricate parts.

Metal Injection Molding

Metal injection molding injects liquefied metal into precise molds. It is best suited for parts weighing between 220 mg and 100 grams. Part tolerances are generally ±0.004 in. per inch of part, giving an accurate product, but the high cost of mold production limits the uses of this process. MIM can be used with a variety of different metal alloys. The products endure a period of shrinkage during the MIM production process that can create variations between batches of the same products and cannot be used for projects that require precise uniformity among high volumes of products. It is not suited for high tensile products as the process results in a product that is often brittle when compared to other precision metal products created using other manufacturing processes.