This invention relates to improvements in hand-held portable sanding machines of the type having a power driven reciprocable shoe carrier to which a sanding shoe is attachable.  More particularly, the invention is directed to the provision of an improved sanding shoe for such machines. 
A feature of the improved shoe of the present invention lies in the organized arrangement of its components, and in the structure for securing a sheet of sandpaper to the shoe. 
Another feature lies in the structure of the shoe whereby the tendency of the sandpaper to tear at its ends is reduced. 
A further feature lies in the structure of clamping mechanism whereby the sandpaper is securely held in place against slipping or pulling free and whereby the clamping mechanism is restrained from being forced during operation of the tool to a released condition. 
A still further feature lies in structure whereby an overcenter type lever for actuating the clamping mechanism is restrained from obtaining a possible jammed condition relative to its pivot support; and other means is provided for locking the lever in its actuated condition against being released by vibration of the tool. 
In accordance with the invention, there is provided in a portable sanding machine including a reciprocable carrier plate, a sanding shoe attachable to the carrier plate for reciprocation with the latter, the sanding shoe comprising a rectangular base plate provided with upstanding studs for mounting it to the carrier plate, opposite ends of the base plate having a smooth surfaced bulbous formation over each of which an end of a sheet of sandpaper is adapted to be extended, and manipulative clamping means mounted upon each of the end surface areas proximate the bulbous ends of the base plate for clamping corresponding ends of the sandpaper to the shoe, the clamping means comprising a lower jaw fixed upon the base plate, an upper jaw angularly movable relative to the lower jaw having an integral back extension of spring material fixed to the base plate normally biasing the upper jaw to an open condition relative to the lower jaw, and a manipulative camming lever pivotally supported upon the base plate having cooperation with the back extension of the upper jaw when pivoted in a predetermined direction to cam the upper jaw angularly downward into the clamping relation with the lower jaw.