Milling of internal and external threads with a thread-profiled milling tool.
The rotary cutter with a thread profile is passed along the walls of an existing hole or along the surface of a cylindrical blank to create threads.
They are available both as solid tools and as tool bodies with cemented carbide inserts.
Compared with the use of taps for threading holes, thread milling eliminates the risk of the tool getting stuck in the hole due to failure while providing better chip removal which reduces the risk of failure.
Another advantage is that one and the same milling tool can be used to cut different thread diameters.
Spiral shaped outer or inner grooves are usually used for fitting