Abstract: A cold knife (10) has a handle (12) within which a receiver bore (34) extends longitudinally. A split collet (38) is slidably mounted within the bore (34) and is configured to receive within a shank groove (40), at any desired longitudinal position therein, the shank (14a) of a cutting blade (14). Because the shank (14a) may thus be selectively positioned relative to split collet (38), cutting blade (14) may be positioned in infinitesimally small increments at a desired degree of extension relative to the cold knife (10). Terminal end (14c) of cutting blade (14) may thus be positioned anywhere from and between extreme positions (P1 and P3) when shank (14a) is clamped within split collet (38) by locking lever (22) moving split collet (38) to place the nose portion (38c) thereof into compressed engagement with reduced-diameter stop portion (34c) of the receiver bore (34).