The present invention provides a material for built up edge formation having a resin block containing a high molecular weight compound having a weight average molecular weight of 5×10.sup.4 or higher and 1×10.sup.6 or lower, a medium molecular weight compound having a weight average molecular weight of 1×10.sup.3 or higher and lower than 5×10.sup.4, and a carbon.

The drill of the invention has: two cutting edges, each having a main cutting edge and a thinned cutting edge, wherein two relief surfaces formed symmetrically around rotation axis, first and second margin portions are formed, the first margin portions have a forward-end small-diameter portion with diameter smaller than the drill diameter, that is formed from the side of the drill forward-end toward the drill rearward-end, the second margin portions have a second forward-end small-diameter portion with diameter smaller than the first forward-end small-diameter portion, that is formed from the side of the drill forward-end toward the side of the drill rearward-end, the first forward-end small-diameter portion and the second forward-end small-diameter portion have inclination portions, the diameters of which gradually increase from the side of the drill forward-end toward the side of the drill rearward-end, and the inclination portions of the first forward-end small-diameter portion have relief surfaces.

According to one implementation, a drill includes the first cutting edges, the second cutting edges and a deflection reducer. The first cutting edges drill a prepared hole to a workpiece. The first cutting edges are formed in a tip side of the drill. The first point angle and each first relief angle of the first cutting edges continuously or intermittently decrease from the tip side toward a rear end side of the drill. The second cutting edges ream the prepared hole. The second cutting edges are formed at positions away in the rear end side from the first cutting edges. The second cutting edges have the second relief angles at a maximum diameter position. The deflection reducer reduces deflection of the second cutting edges. The deflection reducer is formed between the first cutting edges and the second cutting edges. The deflection reducer is inserted into the prepared hole.

A system and method for drilling a hole in a vehicle structure and installing a fastener in the hole. A drill plate having openings and associated machine-readable elements is positioned on the structure. A drill gun is positioned in a particular opening and reads hole information from the associated element, and a computer determines whether the drill gun is properly set-up to drill the hole. A fastener insertion gun is positioned in the particular opening and reads fastener information from the element, and the computer determines whether the hole has been drilled and, if so, whether the fastener insertion gun is properly set-up to insert the fastener. A fastener delivery subsystem stores, tracks, and delivers fasteners to the fastener insertion gun. A system computer monitors the drilling of every hole, the insertion of every fastener, and the overall operation of the fastener delivery subsystem.

A device for machining a work piece creates an electrical potential between an electrode and the work piece or another conducting body proximate to the work piece. The electrical potential establishes an electrical field within the work piece that is expected to repel electrons and create a region of positively charged ions which repel one another. This region is expected to be weakened and material is expected to be removable from this region of the work piece using less force and energy than when machined by traditional machining techniques.

According to one implementation, a drill includes the first cutting edges, the second cutting edges and a deflection reducer. The first cutting edges drill a prepared hole to a workpiece. The first cutting edges are formed in a tip side of the drill. The first point angle and each first relief angle of the first cutting edges continuously or intermittently decrease from the tip side toward a rear end side of the drill. The second cutting edges finish the prepared hole. The second cutting edges are formed at positions away in the rear end side from the first cutting edges. The second cutting edges have the second relief angles at a maximum diameter position. The deflection reducer reduces deflection of the second cutting edges. The deflection reducer is formed between the first cutting edges and the second cutting edges. The deflection reducer is inserted into the prepared hole.

A vibration assisted drilling system is presented. The vibration assisted drilling system comprises a drill feed motion system having a drill feed axis, an oscillation motion system having an oscillation axis, a drill spindle having a drill bit, and a mounting system configured to connect the drill spindle to the oscillation motion system. The drill feed axis is substantially parallel to and offset from the oscillation axis.

A method for hole cutting in a workpiece made of CFRP with a cutting tool including at least one cutting edge is provided. Further, a hole cutting assisting apparatus and an apparatus for hole cutting includes a cutting tool, a drive for rotating the cutting tool, and a heating element configured for heating at least a portion of the cutting edge of the cutting tool.

Provided are a hole formation method enabling the formation of a high-quality hole even when a workpiece material is a difficult-to-machining metal material or a fiber-reinforced composite material and a drill bit used in the method. A drill bit includes at least one cutting edge and a face (a leading flank and a trailing flank) positioned in the vicinity of the cutting edge, and on the face, a recess exhibiting a prescribed planar shape (groove) is provided. A hole formation method includes a hole formation step of machining a portion to be processed of a workpiece material by means of drilling to form a hole while a lubricant material for assisting machining process is in contact with the portion to be processed, and in the hole formation step, the drill bit is used.

A vibration assisted drilling system is presented. The vibration assisted drilling system comprises a drill feed motion system having a drill feed axis, an oscillation motion system having an oscillation axis, a drill spindle having a drill bit, and a mounting system configured to connect the drill spindle to the oscillation motion system. The drill feed axis is substantially parallel to and offset from the oscillation axis.