A high-speed, hand-held attachment for flex rotor shafts of power rotary tools, and also for direct attachment to power rotary tools without flex rotor shafts, that converts rotary motion to
reciprocating motion for precision control of
cutting,
carving, sawing, chiseling, filing, sanding, and
engraving on delicate work pieces. The attachment is one
assembly comprising a one-piece front one-piece
enclosure (20), a rear one-piece
enclosure (30), a high-speed bearing (22), a one-piece rotating piece (40) with integral
cam groove, a one-piece reciprocating piece (50) with an integral
cam follower on one end and with its other, exposed end accomodating the attachment of a chuck or
collet and with geometry to prevent rotation, and a thumbscrew (32). Rotating piece (40) attaches directly to the rotary power source and provides the
cam action drive to reciprocating piece (50). Bearing (22) provides rotative support for the other end of rotating piece (40). Reciprocating piece (50) slidably mounts in front one-piece
enclosure (20). Front one-piece enclosure (20) and rear one-piece enclosure (30) are attached to each other and maintain proper alignment for rotating piece (40), bearing (22), and reciprocating piece (50). Thumbscrew (32) secures the attachment to the flex rotor shaft of a power rotary tool. A
tool holder /
collet is attached to the exposed end of reciprocating piece (50) whereby numerous types of
cutting tools may be utilized. Alternative versions of the rear one-piece enclosure, (30A) and (30B), described herein, allow for attachment directly to power rotary tools without flex rotor shafts. Alternative versions of the reciprocating piece, (50A), (50B), and (50C), and of the rotating piece, (40A), are also described herein.