CLICK HERE FOR INDEX PAGE | ||
MACHINE SCREW, NUTS AND WASHERS | ||
V.Ryan © 2019 | ||
PDF FILE - CLICK HERE FOR PRINTABLE WORKSHEET | ||
|
||
MACHINE SCREW / BOLT NUTS | ||
DOME NUT: Supplied with most machine screws / bolts are nuts, to lock the bolt in position. They are supplied in a range of types and sizes. Dome nuts are regarded as both functional and decorative. They are often chromed as a finish or are manufactured from brass or stainless steel. |
||
HEX NYLON LOCK NUT (left) Lock nuts are used when it is vital that the ‘nut and bolt’, does not rattle loose. Some have a nylon insert, that the machine screws thread cuts into when being tightened. The nylon provides and necessary friction required to prevent ‘loosening’ on the nut. Other lock nuts have a built-in friction ring, which serves the same purpose. |
||
A Castle nut and Split Pin can be used to ‘lock’ a ‘nut’ in place, as shown in the diagram below. The split pin pushes through a hole in the bolt and is deformed through the castle nut, preventing it from loosening. | ||
WASHERS FOR MACHINE SCREWS AND BOLTS | ||
PLAIN WASHER: Washers for machine screws and bolts provide the surface on which the nut or head of the bolt are tightened. When tightened, the force applied to the bolt / nut is distributed evening across the area of the washer. This prevents the area around the head of the bolt and nut from being damaged. | ||
CUP WASHER: These are used in conjunction with countersunk screws (wood screws and machine screws). The machine screw head fits neatly into the cup, providing a professional finish. They are often decorative and can be seen on knockdown furniture and are often brass or chrome finished. | ||
SPRING WASHER (LOCKING WASHER) AND STAR WASHER: A spring washer (also called a helical spring) is designed to prevent a nut from loosening. The ‘spring’ exerts a force against the bolt head / nut, making it less likely that the nut and bolt will loosen. A star washer has the same function, in that it helps to prevent nuts and bolts becoming loose, through vibration or shaking. |
||
RUBBER FLUTED WASHER: A rubber fluted washer provides a waterproof seal for exterior work, such as felting a shed room, when roofing screws are used. The example opposite, shows the rubber fluted washer ‘compressed’ under the force applied through the screw, creating a seal. |
||
CLICK HERE FOR MATERIALS INDEX PAGE | ||
|