| American-type single-spindle screw machine |
A modified automated lathe distinguished by a turret that approaches a workpiece from the axial orientation. |
| automatic bar machine |
A turning machine that continuously cuts a number of parts from a piece of bar stock, one after another. The bar stock advances through the spindle and is held by the collet during the operation. A bar machine is traditionally called a screw machine. |
| axial approach |
A tool approach that runs parallel to the axis of a workpiece. Also called the parallel orientation. |
| bar stock |
Raw material purchased from metal manufacturers in the form of long bars. Bar stock may be round, square, or hexagonal. |
| bar stock magazine |
A chamber that allows the feeding of bar stock, one at a time, into a machine. |
| boring |
The process of using a single-point tool to enlarge a preexisting hole. |
| bushing |
A guide for bar stock on the Swiss-type single-spindle screw machine that enables the creation of very small parts with excellent tolerances. |
| cam |
A circular or cylindrical machine component that converts rotational movement into linear movement. A cam controls the feed rate and depth of cut of cutting tools on the automatic bar machine. |
| chip |
An unwanted piece of metal that is removed from a workpiece. Chips are formed when a tool cuts or grinds metal. |
| chuck |
A device that holds a workpiece in place as it rotates. The chuck commonly has three or four jaws that can be adjusted to fit various sizes of parts. |
| chucking machine |
A general name for any lathe that uses a chuck to hold the part. An operator must load and unload each individual workpiece. |
| CNC turning center |
A sophisticated CNC machine that specializes in turning, boring, drilling, and threading operations, all at the same location. |
| collet |
A slitted device that holds a workpiece in place as it rotates. A collet has a hole through which the workpiece passes, and it is designed to hold specific dimensions. Collets can also be used to hold cutting tools. |
| computer numerical control |
A sophisticated machine tool that uses a computer and special programs to carry out various machining operations. The turning center is an example of a lathe equipped with computer numerical control (CNC). |
| cross slide |
On a lathe, the tool-holding components that allow tools to approach a workpiece from a perpendicular, or radial, orientation. |
| cutoff |
An operation performed on the lathe that uses a cutting tool to separate a finished part from the rest of the stock. |
| cycle time |
The time it takes to make one part. |
| depth of cut |
The amount of material that is removed with one pass of a cutting tool. |
| drilling |
The process of using a multi-point tool to penetrate the surface of a workpiece and make a round hole. |
| drive shaft |
Located in the base of a turning machine, the device that transfers power from the motor to all machine components. |
| engine lathe |
The original and most basic type of lathe. |
| facing |
An operation performed on a lathe that feeds a single-point tool across the end of a cylindrical workpiece to create a flat surface. |
| feed |
The linear movement of a cutting tool into a part to remove material. |
| follower |
A machine component that traces the outline of a cam and thus controls the way a workpiece is cut. |
| form turning |
An operation performed on a lathe that feeds a tool into a workpiece in order to impart the tool's shape in the workpiece. |
| headstock |
The end of a lathe that holds the spindle and the drive that rotates the workpiece. |
| horizontal axis |
An imaginary line that passes through the center of an object and is parallel to the floor. |
| ID grooving |
The process of cutting an internal channel or passageway into a drilled hole. |
| index |
The changing of machine components to a different position. |
| inner-diameter operation |
A cutting operation that takes place on the interior surface of a cylindrical workpiece. |
| lathe |
A machine tool commonly used to create cylindrical parts. A lathe holds a cylindrical workpiece on one or both ends. The cutting tool is gradually passed along the surface of the rotating part. |
| machine motor |
The primary source of power that is located in the base of a lathe. |
| mechanical safety clutch |
A safety device that disengages the drive shaft from the motor. |
| multiple-spindle screw machine |
An automatic bar machine that contains more than one spindle, usually 4, 6, or 8. Multiple spindles allow multiple tools to cut multiple workpieces simultaneously. |
| OD chamfering |
An operation performed on a lathe that feeds a tool to create an angled edge on the workpiece. |
| OD threading |
An operation performed on a lathe that cuts a long, spiraling ridge down the outer surface of a workpiece. |
| outer-diameter operation |
A cutting operation that takes place on the outer surface of a cylindrical workpiece. |
| radial approach |
A tool approach that runs perpendicular to the axis of a workpiece. Also called the perpendicular orientation. |
| reaming |
The process of using a multi-point tool to smooth the interior surface of a hole. |
| screw machine |
An automated turning machine that continuously creates a number of finished parts from bar stock. Bar stock advances through the spindle and is held by a collet. It is also commonly called a bar machine. |
| setup |
Time that is spent setting up the fixtures and tooling, calculating tool offsets, and performing all the necessary tasks to produce the first accurate part. |
| single-point cutting tool |
A cutting tool that uses a single cutting edge to remove material. |
| single-spindle screw machine |
An automatic bar machine that contains one spindle. The spindle rotates one piece of bar stock, which is cut by one tool at any given time. |
| spindle |
The part of the machine tool that spins. On a screw machine, the spindle holds the workpiece. |
| Swiss-type single-spindle screw machine |
A modified automated turret lathe distinguished by a sliding headstock and fixed bushing. Swiss-type machines are capable of creating very small parts with excellent tolerances. |
| tailstock |
A device located at the end of a lathe opposite the headstock that supports the end of longer workpieces. |
| taper turning |
An operation performed on a lathe that feeds a tool at an angle to the length of the workpiece in order to create a conical shape. |
| tapping |
The process of cutting internal threads in a workpiece with a multi-point tool. |
| tolerance |
An unwanted but acceptable deviation from a given dimension. Tolerances indicate the allowable difference between a physical feature and its intended design. |
| turning |
A machining operation used to make cylindrical parts. A single-point cutting tool passes along the outer surface of a cylindrical workpiece as it rotates and gradually removes a layer of material. |
| turret |
The component of a lathe that holds a number of cutting tools. The turret rotates to place tools in the cutting position. |
| turret lathe |
A lathe with a mounted device that holds multiple cutting tools. The turret rotates to position one specific cutting tool in place after another. |
| vertical turning machine |
A turning machine in which the spindle is perpendicular to the ground floor. Vertical turning machines are often used for very large or heavy parts. |
| workholder |
A device used to locate and hold a workpiece in place. |