The turret head cannot be shifted in the bed's lateral direction. In certain turret lathes, the turret head may be moved across, i.e. in the lateral direction of the bed. The collet is used to grasp the work on a capstan lathe. A motorized jaw chuck is used to grasp the work in a turret lathe.
Turret heads are used to vary the position of the cutting tool relative to the workpiece. They are also called as "variable turrets". The most common type of turret head is called "external" or "open" turret head. This type of head can be rotated around an axis that is parallel with the spindle centerline. The second type of turret head is called "internal" or "closed" turret head. This type of head cannot be rotated around its own axis. It can only be shifted laterally along the spindle centerline.
An external turret head is attached to the end of the spindle opposite the faceplate. The head can be rotated through 360 degrees and has anywhere from one to six arms depending on the model. Each arm carries a tool holder which can carry either a single-pointed tool such as a drill bit or a two-pointed tool such as a tap/die set. The tools can be changed without removing the head from the spindle.
An internal turret head is mounted on the spindle near the faceplate. It can rotate but not shift laterally along the spindle centerline.
Manual, horizontal. A "capstan lathe" with a turret was patented in Britain in the late 1830s. Semi-automatic. Machines identical to those described above, but having power feeds and automated turret indexing at the end of the return stroke, are sometimes referred to as "semi-automatic turret lathes." Automatic. Numerical control by computer Vertical and Horizontal. See below.
Turret lathes have a rotating head with tools attached that can be swiveled into the path of a cutting tool held by a spindle mounted on the head. The tool is rotated by an arm attached to its rear end. Turret lathes were developed from capstan lathes, which are manual or semi-automatic versions of the machine. In both cases the tool is rotated by an arbor mounted on the front end of the bed or frame. The capstan mechanism in a capstan lathe consists of a loop of cable or chain attached to the arbor and wound around a drum attached to the headstock. When the operator pulls on the cable or chain, it winds up onto the drum, which then rotates the head with respect to the bed or frame.
In modern turret lathes, the head is usually driven by a motor via a ball screw assembly. This replaces the hand crank used in earlier models. However, some manufacturers still offer hand-operated versions for use in applications where noise is not a concern.
The turret lathe is a type of metalworking lathe used for the repetitive manufacturing of duplicate components that are generally interchangeable due to the nature of their cutting process. Turrets were first developed around 1870 by John Wyatt and William Hancock, who sold them under the name "Wyatt & Hancock." Although they are now made by many different companies, the turret design remains true to its original purpose: creating repeatable parts from stock material.
There are two types of turrets: indexing and non-indexing. Indexing turrets have a single axis of rotation and each part cut on the lathe will be at a different location relative to the center point of the spindle. This means that every time you stop the motor, the cutter will come out of the workpiece positioned at a different place. Non-indexing turrets have two axes of rotation and can produce identical parts with no need for re-positioning of the cutter. They are more complex than indexing turrets but can cut faster because there's less chance that the cutter will come out of the workpiece in the wrong position.
Turrets were originally designed for use with wood, but they can also be used on plastic and metal. The quality of the part produced depends on how well the cutter on the turret matches the diameter of the spindle.
A facing tool is used on the lathe to cut a smooth surface perpendicular to the rotating axis of the work item. A facing tool is installed in a tool holder that is supported by the lathe's carriage. As the tool rotates in the chuck's jaws, it will feed perpendicularly across the part's rotational axis. This action will remove material from the face of the part, producing a flat surface.
There are two types of facing tools: single-cut and double-cut. With single-cut tools, each pass of the tool removes a portion of the workpiece. Double-cut tools make two passes before removing material. The first pass cuts away most of the material using a coarse cutting edge, and the second pass finishes smoothing out the remaining details with a fine cutting edge.
Single-cut facing tools are generally more affordable than double-cut, but they can't reach areas where light traffic needs to be avoided such as near the tail of a lamp housing. Double-cut facing tools have larger kerfs and can remove more material per pass but require more frequent replacement of tool bits.
The type of tool used depends on the job at hand and one's budget. If you need to face small items regularly, then double-cut facing tools are ideal because they provide better value for your money.
Facing tools are available in different sizes for grinding various types of materials.
The bed is the foundation of the lathe machine, upon which all of the other key components are placed. Two longitudinal guideways go over the top of the bed. These guideways are designed with accuracy to guarantee that other elements are aligned correctly. These guideways can also be used by the tailstock. The tailstock has a threaded rod that goes into one of these guideways. This rod is then turned by a nut at the end of it, so that the tailstock can be moved up and down.
There are also two transverse or horizontal guideways. One goes under the spindle head, while the other one goes under the chuck. These guideways allow the tool post to be moved in both directions along the axis of the spindle.
Also included are three vertical guideways. One goes inside the body part being worked on, while the other two go on either side of it. These guideways help position the arm and shoulder during the machining process.
Finally, there is one more component that needs to be mentioned here: the brake. The brake is used to stop the spindle quickly when cutting operations are complete. There are two types of brakes used in practice: mechanical and electronic.
Mechanical brakes use friction to slow down the spindle. This type of brake is usually found on small hand-held power tools such as hedge trimmers and grass cutters.