Dies

A high-quality, reliable threading tool is essential for workshops and industrial businesses that require threads measured to an exact metric thread size, which will give the pitch of the thread in millimetres (mm). At RS, we have thread dies made from both standard steel and high-speed steel (HSS) available, meaning there is a choice of material to best suit your requirements. Our available products cover a range of metric sizes and pitches.

What is a thread die and what are they used for?

Thread dies are special tools used in the manufacturing industry to create the threads on screws, bolts, nuts and other male fixing items. Over time, threads can become damaged and may need rethreading, which dies can also be used for. There are cavities to remove chips and debris as the thread is cut, however, it is recommended to use a chaser for cleaning debris from threads as dies will remove additional material each time they are used on a male thread. This will cause the locking of male and female portions to weaken.

In order to ensure proper alignment during threading, die stocks are often used to hold the die in place and ensure the threading is uniform. The diameter of a die stock can be adjusted slightly to allow for different sized round and hex dies and are tightened to fit the chosen die.

What types of thread die are there?

The external shape of the thread die can be round, square, hexagon or tubular and can be further classified as solid, split or separable. Round dies are the most common and, depending on their size, have three or more serrated cutting edges and geometrically represent the nut thread. There are also left-hand thread dies for applications in which a right-hand thread would cause the male portion to loosen, such as the left-hand pedal on a bicycle.