A tip for twist drill, comprising a super-hard structure joined to a substrate at an interface boundary coterminous with an end of the substrate, the super-hard structure comprising sintered polycrystalline material comprising super-hard grains, the super-hard structure defining a super-hard end surface opposite the interface boundary and a plurality of cutting edges configured for boring into a body in use; the super-hard end surface including a center point or chisel edge, and comprising a plurality of surface regions configured such that respective planes tangential to each of the surface regions are disposed at substantially different angles from the axis of rotation of the tip in use. Precursor constructions for use in manufacturing the tips as well as methods for making the precursor constructions and the tips are disclosed.

Methods of forming a drill bit or boring tool having a cutting edge that includes a pair of generally smooth curvilinear shaped portions that are positioned near the radial outer portions of the cutting edge and connected to one another by a pair of generally linear portions that traverse a longitudinal centerline of the tool.

A drill bit or boring tool having cutting edge that includes a pair of generally smooth curvilinear shaped portions that are positioned near the radial outer portions of the cutting edge and connected to one another by a pair of generally linear portions that traverse the longitudinal centerline of the tool.

One aspect of the disclosure relates to a cutting tool for forming a final opening in a stack that includes at least two layers and a pilot opening having a pilot-opening dimension and extending through at least one of the at least two layers. The cutting tool includes a shank. The cutting tool also includes a first portion including at least one of a first coating or the first coating and a second coating, wherein the first coating at least partially covers the first portion. The cutting tool also includes a second portion between the shank and the first portion, wherein the second portion includes the second coating, and wherein the second coating at least partially covers the second portion.

A drilling tool for producing drill holes includes a tip and a shaft arranged opposite the tip in a direction of a longitudinal axis of the drilling tool. The drilling tool has at least one geometrically defined cutting edge in the tip area, and has an expanded diameter trailing the tip in a longitudinal direction from the tip. The drilling tool has a first area with a first diameter that precedes the expanded diameter, and a second area with a second diameter, larger than the first diameter, that trails the expanded diameter. The drilling tool is distinguished in that the expanded diameter and/or the second area is/are embodied such that chips are produced in the area of the expanded diameter and/or in the second area when a workpiece is machined, chips consistent with those produced when a workpiece is machined with a geometrically undefined cutting edge.

A rotary cutting tool with an elongate body disposed about a longitudinal axis, the elongate body including a helical flute and a polycrystalline-diamond cutting tip. The cutting tip comprises an inner portion having an inner point angle and an outer portion having an outer point angle different from the inner point angle.

A cleaned component having a polycrystalline structure, a method and apparatus for cleaning a leached component to form the cleaned component, and a method for determining the effectiveness of cleaning the leached component. The cleaned component includes a leached layer that has at least a portion of by-product materials removed. The by-product materials were deposited into the leached layer during a leaching process that formed the leached layer. The apparatus and method for cleaning includes a tank, a cleaning fluid placed within the tank, and at least a portion of the leached layer immersed into the cleaning fluid. Optionally, a transducer emits ultrasonic waves into the leached layer. The method for determining the effectiveness of cleaning includes cleaning the leached component to form the cleaned component, measuring one or more capacitance values of the cleaned component, repeating the cleaning and the measuring until achieving a stable lower limit capacitance value.

A rotary cutting tool comprises an elongate body disposed about a longitudinal axis, the elongate body including a helical flute and a polycrystalline-diamond cutting tip. The cutting tip comprises an inner portion having an inner point angle and an outer portion having an outer point angle different from the inner point angle.