A cutting tool includes a novel cutting insert retaining and adjusting mechanism. The cutting insert retaining and adjusting mechanism is associated with a recess in the cutting tool and includes a nest slidably mounted in the recess. The nest includes a cutting insert pocket. The cutting insert retaining and adjusting mechanism includes a first wedge adapted to selectively exert pressure on the nest to retain the nest in a desired position in the recess, and a second wedge adapted to selectively exert pressure on a cutting insert positioned in the cutting insert pocket to retain the cutting insert in a desired position. The mechanism further includes an adjustment screw including a first threaded portion and a second threaded portion. The first threaded portion is threadedly disposed in a threaded bore in the cutting tool body, and the second threaded portion is threadedly disposed in a threaded bore in the nest. The first threaded portion has the same handedness but a different thread pitch as the second threaded portion. Rotating the adjustment screw axially slidably advances and retracts the nest in the recess.

A cutting insert for metalworking operations is retained within a cutting insert holder by a resilient tab on the holder that engages a recess on the stem of the insert. The cutting insert and the holder may be fabricated using rapid prototyping techniques such as 3D printing.

A parting tool is in the form of a blade and a replaceable cutting insert, as well as, a key having an eccentric body. The cutting insert may be clamped in a seat under an elastic, resilient clamping finger. In the blade, a keyhole is formed, into which the eccentric body can be inserted. In the keyhole, there are included concave sliding surfaces, which border on a flat stop surface. With these, convex corner surfaces and flat shoulder surfaces on the eccentric body can interact. By the unique design of the keyhole and eccentric body, a gentle interaction between the surfaces is obtained, which guarantees a long service life of the blade, as well as the key.

A holder for grooving work includes a shank portion, and a head portion located on an end portion thereof. The head portion includes an insert attaching space, an upper and lower respectively located above and below the insert attaching space, a slit extending backward from the insert attaching space, an upper and a lower jaw connecting portions divided by the slit, an upper clamp surface on the upper jaw and a lower clamp surface on the lower jaw opposed to the insert attaching space. A column-shaped groove is connected to the deepest end of the slit. The column-shaped groove is formed to reduce the thickness of the upper jaw connecting portion, and extends from the lateral face on the side of the insert attaching space halfway along the deepest end of the slit toward the opposite lateral face. Upon attaching the insert to the holder the cutting tool is obtained.