The invention relates to a method, a tool receptacle (13), and an apparatus for turning a face of a workpiece (2, 102) with a tool (3), wherein the workpiece (2, 102) is held in a workpiece receptacle (12) rotating about an axis of rotation (100) of a workpiece spindle, wherein, for producing and/or machining a workpiece contour having convex and/or concave portions on the face (20) that extend over defined angles of rotation, the tool (3) and the workpiece (2, 102) are moved back and forth relative to one another in an axial movement along the axis of rotation (100) of the workpiece spindle, said axis being synchronized with the rotational movement of the workpiece (2, 102), and wherein a blade (30) of the tool (3) is aligned at least in the cutting direction and/or transverse to the cutting direction opposite to the surface normals (N) of the workpiece contour to be produced and/or machined, in such a way that an effective clearance angle (α) and an effective cutting angle (γ) remain at least virtually constant opposite to the surface normals (N). The invention relates to a workpiece (2, 102) having a turned face.

Methods of determining movement data representing the movement of a machining tool of an optical lens lathing device for machining one or more optical surfaces or parts thereof of a set of optical surfaces are described. The methods comprise a greatest radial slope amplitude determining step during which the greatest radial slope amplitude of the optical surfaces of the set of optical surfaces is determined. The methods also comprise a machining tool selecting step during which a machining tool having a window angle greater than or equal to the greatest radial slope amplitude of the optical surfaces of the set of surfaces to be manufactured is selected. The methods further comprise a movement data determining step during which movement data representing the movement of the selected machining tool are determined and synchronized with the angular position of the optical surface driven in rotation.

Methods of determining movement data representing the movement of a machining tool of an optical lens lathing device for machining one or more optical surfaces or parts thereof of a set of optical surfaces are described. The methods comprise a greatest radial slope amplitude determining step during which the greatest radial slope amplitude of the optical surfaces of the set of optical surfaces is determined. The methods also comprise a machining tool selecting step during which a machining tool having a window angle greater than or equal to the greatest radial slope amplitude of the optical surfaces of the set of surfaces to be manufactured is selected. The methods further comprise a movement data determining step during which movement data representing the movement of the selected machining tool are determined and synchronized with the angular position of the optical surface driven in rotation.

A method for producing a ceramic honeycomb body having large numbers of longitudinal cells partitioned by cell walls, with its peripheral portion removed by machining, includes rotatably holding the ceramic honeycomb body on a main axis of a lathe, and rotating the ceramic honeycomb body around the main axis, to remove its peripheral portion by machining with a tool; the lathe comprising a first fixing jig on the main axis, and a second fixing jig substantially opposing the first fixing jig; each of the first and second fixing jigs having an abutting end portion opposing each other, the abutting end portion having a smaller outer shape than that of the end surface of the ceramic honeycomb body, and the abutting portion having a substantially flat abutting end surface perpendicular to the main axis.

A method for producing a ceramic honeycomb body having large numbers of longitudinal cells partitioned by cell walls, with its peripheral portion removed by machining, includes rotatably holding the ceramic honeycomb body on a main axis of a lathe, and rotating the ceramic honeycomb body around the main axis, to remove its peripheral portion by machining with a tool; the lathe comprising a first fixing jig on the main axis, and a second fixing jig substantially opposing the first fixing jig; each of the first and second fixing jigs having an abutting end portion opposing each other, the abutting end portion having a smaller outer shape than that of the end surface of the ceramic honeycomb body, and the abutting portion having a substantially flat abutting end surface perpendicular to the main axis.

A turning tool has a cutting element for a lathe that uses metal-cutting technology, wherein the cutting element has a tool blade, wherein the tool blade of the cutting element has a curvature, in a top view, in which the tool blade intersects a tool axis of the cutting element at a perpendicular angle, in which the cutting element has an opening angle with reference to a center point, wherein the cutting element has asymmetry, in such a manner that the tool axis intersects the opening angle outside the center, and in which, in a top view of the cutting element, the curvature of the tool blade has a constant change in radius.