Abstract: The head of a rotary cutting tool has an axially extending slot defining a flat, radially outwardly facing bottom surface and opposite undercut side surfaces, at least one of which makes an acute angle to the bottom surface. A cutter insert has a lower base portion in the slot and a cutting edge on an upper portion. The base portion comprises two wedging elements having opposite complementary tapers in width along their lengths to be relatively lengthwise adjustable for varying the width of the base portion. One wedging element is integral with said upper portion and is releasably maintained under radially outward force to be wedged between the other element and said side surface of the slot, thus holding the cutting edge at a distance from the tool axis determined by the lengthwise adjustment of the wedging elements.

Abstract: A cone hogger unit has axially juxtaposed cutting elements resembling circular saw blades that stepwise increase in diameter from one axial end of the unit. A cutting element intermediate the axial ends of the unit is integral with a body member that has opposite axially projecting hub-like portions, each extending through cutting elements at its axial side of said one cutting element. Circumferentially spaced screws, parallel to the unit axis and at one distance therefrom, pass through the smaller diameter cutting elements and are threaded into said one cutting element. The larger diameter elements are similarly secured by other screws at a greater distance from the unit axis.