a devise used to hold a work piece or a cutting tool within the spindle of a lathe or milling machine. The lathe collet standard is the C5 type collet shown left. The milling collet standard is an R8 type shown right. So popular have these configurations become that many other tools which are not collets have adapted their shanks to fit the collet spindles.
Device used to hold engraving tools at the bottom of the spindle. Can prevent tool drift and shake due to vibration; particularly effective when using a rotary spindle to work with harder substrates, such as stainless steel.
A special kind of chuck that holds the bit more completely around, but has a more limited range, for example 1/8" +/- 1/32" or 1/4" +/-1/16" Most often used when bits are prepared in specific shaft sizes and precision of holding is needed. Router bits commonly come in 1/4" or 3/8" and a router may be supplied with matching collets or only one.
A collet is a holding device that forms a collar around the object to be held and exerts a strong clamping force on the object when it is tightened. It may be used to hold a workpiece or a tool. Collets generally have a narrow clamping range which means a large number are required to hold a given range of materials, unlike a chuck that will generally cover the full range that the machine is designed for.