Abstract: A cutting insert (20) for a machine tool comprising a flat blade formed from polycrystalline diamond material and having a front face (21) thereon formed from the PCD phase (23) with at least one cutting edge (22) thereon, and a rear face formed from the second phase substrate (24), the rear face having serrations (25) therein formed within the second phase substrate (24), preferably substantially normal to each cutting edge.

Abstract: A tube cleaning assembly (10) comprising a cylindrical housing (11) having a bore (20) with a coaxial strut (27) therein, capable of both axial and rotation movement relative to the housing (11). One end of the strut (27) extends through an aperture (29) in an end wall (21) of the housing (11) and is connected to a cleaning brush (17), the other end of the strut (27) being adjacent a piston (26) reciprocable within the bore (11) to move the strut axially, the axial movement of the strut (27) being translated into rotational movement around its axis and rotating both strut and brush.

Abstract: A cutting blade 16, and a method of securing the blade 16 in a reamer 11 having an axial recess 19 in the body 13 of the reamer. The cutting blade 16 has parallel serrations 35 in its rear face 37 extending normally of each cutting edge 34 and is clamped to mutually interengagable parallel serrations 36 on the reamer 11 which extend radially thereof. The cutting edge 34 of the blade 16 is adjusted to a new position by movement of the blade along the radial serrations 36 using a single adjuster means 42.

Abstract: A cutting blade 16, and a method of securing the blade 16 in a reamer 11 having an axial recess 19 in the body 13 of the reamer. The cutting blade 16 has parallel serrations 35 in its rear face 37 extending normally of each cutting edge 34 and is clamped to mutually interengagable parallel serrations 36 on the reamer 11 which extend radially thereof. The cutting edge 34 of the blade 16 is adjusted to a new position by movement of the blade along the radial serrations 36 using a single adjuster means 42.

Abstract: A cutting insert for a borer or reamer comprising a flat blade having a front face with at least one cutting edge, the front face having at least one depression, or dimple, having clamping faces therein which are frustoconical and which in use engage a clamping screw whereby the blade is held in the reamer. The clamping faces extend in a direction parallel to the cutting edge, and the depth of the depression changing continuously in longitudinal cross-section.