What are Coach Screws?
Coach screws are heavy duty screws designed for metal to timber connections, or to join heavy timbers. Coach screws are also known as lag bolts or lag screws, and they have a square or hexagonal head engineered to be used with a wrench, spanner, or pliers. Coach screws come in a wide range of sizes, from the very small ones packed with furniture designed to be assembled by the consumer to extremely big ones used in large scale construction projects. Coach screws consist of an externally threaded cylindrical shaft that tapers to a point, with a head at the other end. When coach screws are driven into timber, the threads bite into the wood, while the head stops the screw from going all the way through as it provides compression. The essential form of the screw has been in existence for over 2,000 years, although metal screws for construction and woodworking have only been in use since it became possible to mass-manufacture them in the late 19th century. It was not until the Second World
