Glossary

Boring
A machining process that produces a round straight hole using a single point tool.

Chamfer
Usually a 45 degree angle machined on the start of a bore or a shaft to allow for ease of assembly.

Computer numerical control (CNC)
The control of a machine tool using coded instructions from a programmer or an operator.

Counterbore
Enlarging the end of a previously created hole.

Countersink
Creating a tapered hole on the end of an existing hole to accommodate a tapered head screw.

Drill press
A machine used to produce holes in workpieces; reaming, tapping, spot facing and countersinking can also be performed on drill presses.

Grinder
A machine that removes material from workpieces using abrasive wheels.

Heat treatment
The heating and cooling of metals to modify their mechanical properties.

Knurling
Using a tool to produce a pattern on the diameter of a workpiece in a lathe.

Lathe
A machine that holds and rotates the workpiece; a cutting tool is moved on slideways to cut cylindrical, tapered or threaded features on a workpiece.

Machinery’s handbook
A reference book used by the mechanical engineering disciplines such as engineers, toolmakers and machinists.

Mill
A machine that holds the workpiece while a rotating cutter with single or multiple cutting edges cut surfaces and contours.

Saw
A machine commonly used to cut off workpieces from bar stock using a multi-tooth blade.

Spot facing
A machining operation that creates a flat surface at 90° to a hole.

Tapping
Cutting threads within a hole using a cutting tool called a tap.

Traverse grinding
Grinding using an automatic feed.

Trepanning
Cutting a groove in the form of a circle or boring or cutting a hole by removing the center or core in one piece.