Threads on nuts, bolts, pipes, and other hardware and equipment hold our world together. And a machinist makes sure those threads are correct so everything will stay together longer. Threads make the use of our lathes, micrometers, as well as other machines and machinist tools possible. External male threads need internal female threads to mate or fasten objects together. The screw is made of two simple machines – the inclined plane and the wedge - so that it can move forward while also holding objects together so that the threads are unable to slip from their position. Image courtesy of FLYD The varied uses of threads, thread angles, ridge pitch, coarse and fine threads, thread depth and diameter, and other variations make each thread unique for its use. Each of these variations plays a major role in how the threads can be used without stripping. So, you can see how important it is to get your measurements correct when making these types of parts that require threads. Of course, I