A rotary cutting tool or end mill is provided, the tool comprising a plurality of pairs of diametrically-opposed, symmetrical, helical flutes formed in a cutting portion of the tool body, wherein the pitch between at least one pair of adjacent helical flutes is less than or greater than the pitch of at least one other pair of adjacent helical flutes in at least one radial plane along the axial length of the flutes, a plurality of peripheral cutting edges, wherein at least one of the peripheral cutting edges has a radial rake angle different from radial rake angle of a peripheral cutting edge of a different helical flute.

A cutting tool system is designed to have a combined sinusoidal-shaped and helical-shaped cutting edge formed by an assembly of aligned common cutting inserts each having a sinusoidal and helical cutting edge.

A cutting tool system is designed to have a combined sinusoidal-shaped and helical-shaped cutting edge formed by an assembly of aligned common cutting inserts each having a sinusoidal and helical cutting edge.

A method for manufacturing a cutting tool includes a rake face forming of forming a rake face in a substrate serving as a base of the cutting tool, a flank face forming of forming a flank face in the substrate serving as the base of the cutting tool, a rounded face forming of forming a rounded face between the rake face and the flank face, and an R-value calculating of calculating an R-value which is a value of a radius of the rounded face to be formed in the rounded face forming.

A method for manufacturing a cutting tool includes a rake face forming of forming a rake face in a substrate serving as a base of the cutting tool, a flank face forming of forming a flank face in the substrate serving as the base of the cutting tool, a rounded face forming of forming a rounded face between the rake face and the flank face, and an R-value calculating of calculating an R-value which is a value of a radius of the rounded face to be formed in the rounded face forming.

An adzer bit includes a support member that defines a through hole that is configured to receive a fastener. The support member includes a cutting segment cap portion and a base portion. The support member also defines an annular slot that is axially disposed between the cutting segment cap portion and the base portion. A plurality of cutting segments are received and secured in the annular slot. The material of the plurality of cutting segments is harder than the material of the support member.

A method of making a super-hard article comprising a super-hard structure (14) bonded to a substrate (18), the super-hard structure comprising a sintered plurality of super-hard grains. The method includes providing raw material powder suitable for sintering the super-hard structure. The raw material powder is combined with organic binder material in a liquid medium to form paste. The content of the raw material powder is more than 60 and less than 85 mass per cent of the paste and the composition of the paste is such that it has a shear rate of at most 25 inverse second (s-.sup.1). A substrate assembly is provided, which comprises the substrate, having a formation surface area configured for forming a boundary of the super-hard structure, the substrate comprising a recess coterminous with the formation surface area. The paste is extruded into contact with the formation surface area to provide a paste assembly. The paste assembly is heat treated to remove the binder material and provide a pre-sinter assembly. The pre-sinter assembly is subjected to a pressure and temperature sufficient to sinter the raw material powder and transform it into the super-hard structure bonded to the substrate at a boundary coterminous with the formation surface area. The super-hard material is diamond or cubic boron nitride.

A method of making a construction comprising a polycrystalline super-hard structure joined to a side surface of an elongate substrate. The method includes: providing a vessel configured for an ultra-high pressure, high temperature furnace, the vessel having an elongate cavity for containing a pre-sinter assembly and defining a longitudinal axis, the cavity having opposite ends connected by a cavity wall. The pre-sinter assembly comprises the substrate, an aggregation comprising a plurality of super-hard grains arranged over at least a part of the side surface of the substrate, and a spacer structure configured for spacing the substrate apart from the cavity wall. The spacer structure comprises material having a Young's modulus of at least 300 GPa. The method further includes inserting the pre-sinter assembly into the cavity, the substrate being substantially longitudinally aligned and the spacer structure arranged between the side surface of the substrate and the cavity wall; applying a force to the pre-sinter assembly and heating it to a temperature, the force being sufficient to generate a pressure within the vessel for sintering the aggregation at the temperature, and providing the construction.

A method of making a construction comprising a polycrystalline super-hard structure joined to a side surface of an elongate substrate. The method includes: providing a vessel configured for an ultra-high pressure, high temperature furnace, the vessel having an elongate cavity for containing a pre-sinter assembly and defining a longitudinal axis, the cavity having opposite ends connected by a cavity wall. The pre-sinter assembly comprises the substrate, an aggregation comprising a plurality of super-hard grains arranged over at least a part of the side surface of the substrate, and a spacer structure configured for spacing the substrate apart from the cavity wall. The spacer structure comprises material having a Young's modulus of at least 300 GPa. The method further includes inserting the pre-sinter assembly into the cavity, the substrate being substantially longitudinally aligned and the spacer structure arranged between the side surface of the substrate and the cavity wall; applying a force to the pre-sinter assembly and heating it to a temperature, the force being sufficient to generate a pressure within the vessel for sintering the aggregation at the temperature, and providing the construction.

A micro end mill includes a shank made of a first material and a cutting tip made of a second, different material that is bonded to the shank. The first material can be, for example, carbide or high speed steel (HSS), and the second material can be, for example, cubic boron nitride (CBN), polycrystalline cubic boron nitride (PCBN), ceramic or polycrystalline diamond (PCD). The micro end mill is manufactured by producing a billet made of Superhard material using laser radiation, bonding the billet to a shank of the end mill, and removing material from the billet using laser radiation to produce a cutting tip made of the Superhard material. The laser radiation may comprise a laser beam encased in a water jet or a laser beam with a non-Gaussian intensity profile.