Lathe Turning Metal Lathe Turning Metal
If you are interested in lathe turning, there are a few basics you should know about lathes and the turning process.
Types of Metal Turning Lathes
The three most common types of lathes are the engine lathe, which is the kind most often used by machinists and hobbyists, the toolroom lathe, which is more expensive and usually consists of better parts for the most accurate usage, and the turret lathe, which allows for multiple cutting operations to be performed in rapid succession.
Lathes are made with many variable components. Some lathes are more complicated than others, but most contain the same basic parts. Generally, lathes consist of a headstock to house the main spindle, change gears and speed mechanism, and a bed, which serves as a base for the headstock and allows for parallel alignment of the carriage and tailstock with the spindle. The carriage is the part of the lathe that holds and moves the tool bit for turning and facing, and the tailstock is located directly opposite from the headstock on the spindle axis and also houses tools.
Turning refers to cutting a cylindrical workpiece by rotating it against a fixed, single-edged tool, which must be parallel to the axis of rotation. Turning performed on the interior of a workpiece by a lathe is more commonly known as “boring”.
Facing is often the first and last operation involved in preparing a workpiece. This process is used to flatten off the end of a workpiece by removing excess metal. In facing, the cutting tool is placed at a right angle to the axis of rotation to produce a clean, straight edge through the application of lateral force.
In grooving, small notches or grooves are cut into the workpiece at specific depths with the use of a blade-like tool. Grooves can be made internally, externally or on the face of a workpiece.
Parting is similar to grooving. During this operation, deep grooves are made to sever a portion of the workpiece from a larger piece. Parting is most often used to remove a completed or semi-completed component from the bar stock. It can also be used for other miscellaneous purposes, such as cutting off the head of a bolt.
Drilling is the process in which drill bits, held in a fixed position by the tool turret or tail stock of the lathe, are used to remove the metal from the inside of a workpiece. Before drilling, you will need to start the hole off with a center drill, otherwise the hole will likely go off center.
Threading refers to all types of interior and exterior thread cutting. This is among the most demanding of all the lathe turning operations for several reasons. One of these is that the cutting force is usually higher in threading, while the radius of the insert is smaller and weaker, making mistakes much more difficult to avoid.