To create an internal thread with a lathe, a cutting tool must be used. This specialized tool is carefully attached to the headstock, where it is directed by the spinning spindle of the machine. Most frequently, lathes are equipped with a straight fluted component. This straightened protrusion has been honed to the exact measurement needed to form the thread.
After your workpiece is securely nestled in a three-jaw chuck, ensuring it is perfectly aligned with the spindle of the lathe, you can begin cutting internal threads. The tool that comes into use here is the internal threading tool, which you’ll need to install in the headstock of the lathe. Once that’s taken care of, you can begin threading.
To begin, the RPM of the lathe’s spindle must be adjusted to the required level for the type of thread being cut. Usually, when it comes to internal threading, the cutting speed is lower compared to other kinds of lathe operations. That’s simply because the whole length of the spiral thread is being cut, so a slower speed enables the tool to ascend without snapping.
The cutting tool on the lathe is provided with the opportunity for efficiency and accuracy, as long as the speed is set properly. Once that is ensured, the appropriate depth of the cutting tool can be achieved by using the cross-feed handle. This small, yet important step involves adjusting the handle until it slightly grazes the workpiece, followed by moving the carriage until the desired level of depth is accessed.
Activating the lathe, the cutting tool is then navigated into the workpiece, guided by a precise depth and rate of travel. As it continues to slice through the material, the tool is kept on course until it reaches the required length of thread before ceasing its progress.
The threading tool is withdrawn from the workpiece and the lathe ceases its operation. The piece is then taken from the lathe and checked if the internal thread is up to standard. If this has not been accomplished, the cycle must be resumed until an appropriate thread has been formed.