In a working machine, left and right side walls are erected on a bed, a forward/backward saddle is movable in forward/backward directions, left and right sides of the forward/backward saddle are movably supported with the left and right side walls, a forward/backward drive device is arranged on the left and right side walls, to move the forward/backward saddle in the forward/backward directions, a left/right saddle is arranged on the forward/backward saddle and movable in left/right directions, a left/right drive device is arranged on the forward/backward saddle on each of forward/backward sides of the left/right saddle, to move the left/right saddle in the left/right directions, an up/down slider is movable up and down and arranged on the left/right saddle, a lower portion of the up/down slider is provided with a processing head to which a processing tool for processing a work set on the bed is removably and replaceably attached.

A router power tool including a housing mounted to be moveable with respect to and spaced from a base, said housing including a motor to rotate a shaft which includes, at its free end, a tool holder for a cutting tool, said shaft extending from the housing such that the tool holder is located at or adjacent to the base and said housing is connected to the base by at least one extendable assembly. The power tool is selectively locatable with a guide plate via retaining means. The guide plate includes apertures for the receipt of retaining means to allow the power tool to be engaged therewith and datum tabs to contact with the power tool to ensure the accurate location of the power tool with the guide plate when held in position by the retaining means.