Abstract: A plunge cutting device for use with a portable drill, drill press, or other rotary drive source which is capable of cutting irregularly shaped openings or workpieces in a single operation. A drive chain, belt, or other means carries a plurality of cutting teeth along a path defined by a series of chain guides. A lower plate, adjacent the surface being cut serves as a finer resolution guide for the cutting teeth to define their cutting path. The configuration and orientation of the cutting teeth causes them to push inward against the edge of the plate so that they follow its shape closely. A preferred shield encloses the teeth, chain, and drive mechanism for safety and to serve as a vacuum shroud for dust collection. The shield may also act as a guide, holding the teeth in position prior to the start of the cutting operation.

Abstract: A cutting tool having spaced elongate teeth. The tool facilitates 1) the removal of cut particles from the surface to be cut thereby enabling efficient cutting particularly of deeper holes; and, 2) the removal of the center cut out portion from the cutting tool. The tool comprises: a pilot drill bit; an anchoring disk fixed to and around a rear central portion of the drill bit; a plurality of peripherally spaced elongate teeth each having a rear end portion held in the anchoring disk, and a front end portion having a cutting edge; a sliding guide disk slidably positioned around the drill bit and in front of the anchoring disk so that the elongate teeth are radially positioned thereby; bias means to bias the sliding guide disk in a forward position; and, retention means to prevent the guide disk from sliding forwardly on the pilot drill bit beyond the cutting edges of the teeth.

Abstract: The traditional method of carving out an electrical outlet box opening in a log wall consists of chiselling after a series of closely spaced holes are drilled in the log. It is a time consuming and difficult undertaking. An apparatus for quickly and easily cutting a rectangular opening in a log wall is disclosed. The apparatus comprises: a saw jig, having a central opening, for mounting on an upright side of the log wall; a cutting drum having teeth around its periphery; drive means to revolve the cutting drum; and, a guide arm attached to the jig to guide the revolving drum into the central opening. Most preferably the drive means is a chain saw. A method of cutting a rectangular opening in a log wall comprises the following steps: mounting a jig having a central opening and a guide arm, on an upright side of the wall; and, guiding a revolving drum having teeth on its periphery through the central opening into the wall using the guide arm on the jig.

Abstract: There is a need for an efficient cutter to cut openings in drywall for electrical switch and outlet boxes. Existing cutters typically press out an opening and consequently require great hand supplied force and use of a back plate which must be positioned behind the wallboard.

Abstract: An end shaft mounted clutch which is inexpensive to produce, maintain, and install, even on an existing belt driven lawn mower.