Abstract: A tool has a tool body which defines a first seat into which is secured an anvil. The anvil and the tool body define a second seat into which a backup plate is located. The backup plate has a longitudinally extending groove which is used to locate a form tool cutting insert. A first clamp assembly exerts a clamping force on the insert and backup plate against the anvil in a first direction. A second clamp assembly exerts a clamping force on the insert and backup plate against the anvil in a second direction, the second direction being approximately 90.degree. to the first direction. The insert has a cutting surface of a predetermined configuration on two opposite sides such that indexing of the cutting insert 180.degree. will position the opposite cutting surface in the machining ready position. The backup plate has a complementary predetermined configuration to support each of the cutting surfaces of the insert. The clamping of the insert and backup plate against the anvil in two directions approximately 90.