Coach Screws
Coach screws are a heavy-duty method of fixing timbers together or for fixing metal sections or ironmongery to timber. The main differences between a coach screw and a woodscrew is that where woodscrews range in sizes between 3mm and 6mm thickness, coach screws range from 6mm to 12mm diameter thickness so they are a much heavier duty fixing.
The hexagon head means that more torque can be applied with either a spanner or an impact wrench.
Washers can be used with the coach screws to give a flat surface for the bolt to fix against and also to reduce the chance of the timber splitting as the screws is tightened. At Fastco we have repair washers ranging in sizes between 20mm and 50mm in diameter.
It is advisable to drill a pilot hole in the timber before fixing as this will reduce the chances of splitting the timber, particularly when working close to the edge.
For certain types of wood such as oak it is better to use stainless steel coach screws as the acid in this variety of timber corrodes carbon steel coach screws.
Coach screws can also be used to fix to concrete, brick, stone and block when used with plastic wall plugs, giving a neat hexagon finish. At Fastco we have a wide range of standard wall plugs and speciality wall plugs by Fischer for more demanding applications as well as fixing into cavities.
See our blog - Coach Screws: Your complete Guide