A folding mounting base is provided to convert a portable hand tool such as a portable band saw into a fixed tool which may be used on a workbench. The mounting base has upper and lower cradles, the upper cradle folding down next to the lower cradle for storage. In use, the handle of the portable tool in placed in the upper and lower cradles, and held in position by a toggle clamp. The toggle clamp engages the hand tool trigger to maintain the tool in an operating condition.