A "bent bolt" having the unthreaded end reverse bent to approximately a semicircle.
A machine screw with a small oval head. (Trimmed oval head).
(1.) A second nut forced or jammed against the main nut to prevent loosening.
(2.) A thin nut.
A small block or wedge inserted between shaft and hub to prevent circumferential movement.
The recess cut for Woodruff keys produced by sinking a milling cutter of the right diameter and width into a shaft.
A groove or slot cut to fit a key. A key fits into a key seat and slides into a keyway.
A roughened surface produced by contact with a wheel which forces metal above the surface while making indentations below the surface.
A fastener having a square head, with a gimlet or cone point, and a thin, sharp, coarse-pitch thread, designed for insertion in wood or other resilient materials and producing its own mating thread.
A variation in the distance between the threads of a screw.
A thread is a left-hand thread, if, when viewed axially, it winds in a counter-clockwise and receding direction. All left-hand threads are designated LH.
Length of Fastener
The length of a flat bearing surface fastener is the distance, in a line parallel to the axis, from the bearing surface to the extreme point. The length of a countersunk head fastener is the distance, in a line parallel to the axis, from the largest diameter of the bearing surface to the extreme point.
Lentil Head Screw
Obsolete term for oval head screw.
A metal finishing process by forcing a stream of liquid, in which a very fine abrasive is suspended, against the surface to be finished.
A nut which, in addition to serving the purposes of an ordinary nut, has a special means for gripping a threaded member so that a relative rotation between the nut and the threaded companion member is prevented in use.