metalreamers

Metalreamers are a type of cutting tool used in machining operations to enlarge and finish existing holes. They are characterized by their multiple cutting edges, which typically number from two to twelve, arranged helically around a cylindrical body. The primary function of a metalreamer is to achieve a precise diameter and a smooth surface finish in a pre-drilled or cored hole. This contrasts with drilling, which creates a hole, or boring, which enlarges a hole but typically with a single point cutter.

The cutting action of a metalreamer is primarily one of shaving rather than removing large amounts of material. As the reamer rotates and is fed into the workpiece, its cutting edges shear off a thin layer of material, refining the hole to its final dimensions. This process results in superior dimensional accuracy and surface finish compared to drilling alone. Metalreamers are available in various forms, including straight-fluted and helical-fluted designs, with the latter being more common due to their ability to provide a smoother cutting action and better chip evacuation, especially in tougher materials.

The materials used for metalreamers vary depending on the application and the workpiece material. High-speed steel (HSS) is a common choice, offering a good balance of hardness and toughness. Carbide-tipped or solid carbide reamers are used for harder materials or for applications requiring extreme wear resistance and longer tool life. The flutes can also be coated with specialized materials to further enhance performance and durability. Proper reaming technique involves using the correct cutting speed, feed rate, and lubrication to prevent tool wear and achieve the desired hole quality.