Hardened steel self-tapping screws do not require pre-drilled pilot holes, even in hardwoods and laminated boards. Joints between other material thicknesses will retain a similar degree of strength and tightness and can be further reinforced by inserting pocket screws from opposing faces. The optimum material thickness is 19mm ensuring that the exit point of the screw is centred across the thickness (i.e. The first position is used to accommodate material between 16 and 18mm, the second between 18 and 38mm. To accommodate material thicknesses of between 16 and 38mm, there are two alternative toggle clamp-mounting positions on the base plate and an adjustable clamping pad. The minimum material width accommodated by the jig is 38mm. jointing screw centres) to be adjusted between 29 and 63mm. The column-clamping rod allows the distance between the drill guide centres (i.e. These bushes are set at a precise angle to achieve the correct skew angle for the joint fixing screws. Two hardened steel bushes are set into each of two vertical aluminium columns clamped to the base plate via a clamping rod and vertical end stop. The Pocket hole jig consists of an aluminium base plate fitted with a horizontal action toggle clamp. Trend T12 & T14 2300w Variable Speed 1/2' Plunge Routers.