Vises

A vise (American English) or vice (British English) is a mechanical apparatus used to secure an object to allow work to be performed on it. Vices have two parallel jaws, one fixed and the other movable, threaded in and out by a screw and lever.

Woodworking vices are attached to a workbench, typically flush with its work surface. Their jaws are made of wood or metal, the latter usually faced with wood, called cheeks, to avoid marring the work. The movable jaw may include a retractable dog to hold work against a bench dog.

"Quick-release" vices employ a split nut that allows the screw to engage or disengage with a half-turn of the handle. When disengaged the movable jaw may be moved in or out throughout its entire range of motion, vastly speeding up the process of adjustment. Common thread types are Acme and buttress.

Traditional workbench vices are commonly either face vices, attached to the front of the workbench, near the left end (for a right-handed worker) or end vices, attached to or forming part of the right end of the bench.

One common variety of face vice is the leg vice, which has a long extension down to the floor, with a provision to adjust the spacing of the bottom of the leg, to keep the clamping surfaces of the jaws approximately parallel, even though the work to be clamped may be of various thicknesses.

An engineer's vice, also known as a metalworking vice or machinist's vice, is used to clamp metal instead of wood. It is used to hold metal when filing or cutting. It is sometimes made of cast steel or malleable cast iron, but most are made of cast iron. However, most heavy duty vices are 55,000 psi cast steel or 65,000 psi ductile iron. Some vices have a cast iron body but a steel channel bar. Cast iron is popular because it is typically 30 ksi grey iron which is rigid, strong and inexpensive. The jaws are often separate and replaceable, usually engraved with serrated or diamond teeth. Soft jaw covers made of aluminum, copper, wood (for woodworking) or plastic may be used to protect delicate work. The jaw opening of an engineer's vice is almost always the same size as the jaw width, if not bigger.

...
Wikipedia