threadmilling

Threadmilling is a machining process used to create internal or external threads. It employs a rotating milling cutter that moves in a helical path around the workpiece. This path precisely follows the diameter and pitch of the desired thread. The cutter, often a specialized form milling tool, has multiple cutting edges that engage the material in small increments. As the cutter moves along the helical path, it gradually removes material, forming the thread profile.

This method offers several advantages over traditional thread cutting or tapping. Threadmilling can produce threads in materials that are difficult to tap, such as hardened steels or exotic alloys. It also allows for the creation of threads in materials with interrupted surfaces, like those with keyways or cross-holes, where a tap might snag. The process generates less cutting force compared to tapping, reducing stress on the workpiece and the machine. This can lead to improved thread accuracy and surface finish.

Furthermore, threadmilling is well-suited for creating threads in deep holes, as it avoids the risk of tap breakage that can occur when a tap reaches the bottom of a deep cavity. The tool path can be programmed to control chip formation, leading to more manageable chip evacuation. The process is typically performed on CNC milling machines, allowing for precise control over the helical motion and cutter engagement. It's a versatile technique for manufacturing various thread types, including standard metric and inch threads, as well as specialized forms.