Abstract: The apparatus comprises a crank arm in a crank-arm press with a curved tool at the end of the crank arm being constrained to move so the curved tool makes rolling contact across a flat, stationary substrate. The crankshaft rotates about an axis, the crank arm is rotatably mounted at one end to the crankshaft, a curved tool is mounted at the other end of the crank arm, a line on the surface of the curved tool and parallel to the crankshaft axis of rotation is constrained to move perpendicular to a plane while the curved tool is in rolling contact with the substrate, said plane being the plane of the flat stationary substrate, the radius of curvature of the curved tool being greater than the length of the crank arm; and with the radius of the curved tool, the length of the crank arm, and the eccentric radius of rotation of the crankshaft being selected to maintain the contact line of the curved tool in the substrate plane during the rolling contact.