How to Cut Threads on a Lathe? – Easy Thread Cutting Guide

If you are a non-techno person and have zero knowledge about the threads and lathe machine, then firstly, let me clear that here the threads are metal threads. They need a precise feed rate to pitch and cut with accuracy. The nose radius varies from your need to cut the thread, and it is strictly limited too. There are various methods used by people for cutting the thread, and in the early days, people used to cut the threads with a manual lathe and not the machine once that we use today.
How to Cut Threads on a Lathe?
So, if you are interested and want to know how to cut threads on a lathe, then keep reading, and you will know the easy thread cutting methods. Four infeed methods can be used for cutting threads on a lathe. They are listed below:
Flank infeed
The flank infeed method has parallel thread flanks, and this direction means that it has a 30-degree line feed. The parallel framed chip provides conventional turning. It is easier to form than other infeed methods and also offers better dissipation. The trailing edge of the lathe here rubs the flank instead of cutting it that burnishes the metal thread. This may create an inferior surface and be weaker, too, though the results are good to go.
Modified Flank infeed
Generally, modified flank infeed is almost similar to the flank infeed method. The only difference is the angle. It has a lower angle than 30 degrees. Here the advantage of using this method is that it eliminates the risk of inserting the thread to the trailing edges. After the study and research, it is acceptable and guaranteed to get the best results of cutting thread with this method. It has 29½ degree angle infeed that practices the best way to cut the thread between 25 to 29½ angles.
Alternating Flank infeed
In an alternating flank method, both the thread flanks are required, and they are inserted alternately. Thus this method is known as an alternating flank infeed method. When you cut the thread with this method, it gains a longer tool life. This method also delivers excellent results due to the two side usage of the nose. The only issue here with alternating flank infeed is that it may result in chip flow issues and may affect the surface of the tool, too, although alternating flank infeed method is used to form threads like Acme and Trapeze.
Radial infeed
The radial infeed method is one of the most common ways that is used to produce threads, and thus it is not recommended thoroughly. Here the tool is placed perpendicular to the workpiece and center. In the radial infeed method, the metal is removed from both the sides of the flanks and thus gives a V-shaped chip in the result. The v-shaped chip is always difficult to break and therefore, might have a flow problem. The tool life with radial infeed method is shorter than other methods. They are less durable due to high heat and pressure on both sides of the nose.
Technology improves every now and then. The best way to cope with modern culture is to keep trying the methods. All of these methods are evolved and used, keeping different end results in mind. Earlier, only a manual lathe method was used to cut the thread, and it was really tiresome. The manual lathe method didn’t always give the perfect cut thread and is also considered risky to handle. Usually, there are always some or the other technical problems that every manufacturer faces while using these methods. Thus regular up-gradation of the method is done to gain the best results possible. Handle your machine with care, and you can handle all the threads too.