A lathe is an engineering marvel that can be used for performing a plethora of operations, such as cutting, drilling, sanding, knurling and deformation. The machine is designed to spin the workpiece around an axis of rotation, and can even be fitted with suitable attachments to help cut external threads on the same.
The main elements of a lathe are the headstock, the tailstock and the bed. Located atop the bed, the headstock houses a motor that rotates a spindle – a piece which holds the workpiece. On the other end of the bed lies the tailstock – offering support to one end of the workpiece while anchored to the floor. The bed’s main function is simply to hold the headstock and tailstock in their respective positions.
Variety in the lathing process is found through the utilization of different types of lathes. Of the most common are engine, turret and computer numerical control (CNC) lathes. Engine lathes are known for their capability to cut cylindrical, tapered and threaded parts. But a variation on engine lathes, turret lathes include a special component containing multiple tools that permit one to conduct multiple operations on the same piece without needing to relocate it. Going beyond engine and turret lathes, CNCs take the process a step further having computer-based abilities that enable them to do highly complex operations.
To produce threads on the outside of a lathe, one relies upon a taps and dies set. Held within the arsenal of this set is a tap, responsible for cutting the inner threads, as well as a die designed to carve out the external ones.
The tap is an object equipped with an ordered array of threads along its circumference, while the die is slick and round with a single cavity occupying its center. This space is ever so slightly bigger than the exterior of the tap.
The cutting of internal threads begins when the tap is inserted into the predrilled hole in the workpiece before turning it. As the tap is rotated, it chips away at the edges of the hole, forming threads that run its interior.
The method of creating an external thread is achieved by rotating a die over the end of the workpiece. As it rotates, the die carefully carves a thread into the material.
To ensure precise and accurate drilling, the taps and dies set is equipped with a tap wrench and die holder. The tap wrench allows you to grip the tap securely while it’s inserted and rotated. The die holder, on the other hand, enables you to securely grasp the die, so it can be rotated to form threads for hole forming.
A single-point cutting tool can be utilized to produce external threads. This type of tool is securely attached to the lathe spindle and then fed into the object to cut its thread.
While taps and dies sets are straightforward to use, single-point cutting tools are more demanding and require more expertise. Despite the increased difficulty, these cutting tools boast versatility, affording users the capability to cut a range of various thread types.
Thread-creation on a lathe is simplified with the implementation of taps and dies sets. The tools required to achieve such a task are widely available and allow for the manufacture of precise, pristine threads with minimal effort.