A fastener includes a shank having a first end and a second end. The fastener also includes a thread provided on the shank, the thread including a first region having a first thread angle and a second region with a second thread angle, at least a portion of the thread having said first thread angle. The fastener also includes an arcuate detent region in the shank between respective turns of the thread.

Various embodiments provide a post-to-beam fastener including a head, a tip, and a threaded shank connected to the head at a first end and the tip and a second end. In various embodiments, threaded shank includes a longitudinal axis extending from the head to the tip, and the tip includes a recess operable to removably receive a drill bit to the fastener.

A self-tapping fastener or screw is provided including a head, a cutting tip, and a body portion. The cutting tip includes a first cutting surface. The body portion extends from the head along a central axis to the cutting tip. The body portion includes a proximal threaded portion having a proximal thread size; a distal threaded portion having a distal thread size, the distal thread size being smaller than the proximal thread size; and an intermediate portion, the intermediate portion of the body portion disposed between the proximal threaded portion and the distal threaded portion.

A fastener includes a head with a top face and a conical bottom face, and a shank with a threaded portion spiraling thereon and a drilling portion. The head includes a plurality of cutting portions and cutting ribs formed on the bottom face to thereby cut and shave fibers and accommodate chips. Each cutting portion extends towards the shank and includes a projecting blade formed circumferentially of the top face, and an adjoining wall and a flank wall respectively connected to the projecting blade and meeting at a cutting edge. The cutting ribs extend radially relative to the shank. The cutting portions and the cutting ribs cooperate to continue cutting and press remnants and the bulge down so that the head fits flush with the surface of the workpiece to thereby increase the evenness and the fastening effect after the head is fastened in position.

A self-drilling, self-tapping bone screw is described in which the bone screw has a drill tip free of threads and having a length at least as great as about the thickness of a proximal cortical bone layer, with the drill tip having opposed lands and a helical flute between each of the lands with each of the lands having a cutting edge configured to cut bone as the drill tip is rotated into the bone with the flutes conveying the bone debris away from the drill tip, where a lead thread begins to self-tap internal threads in the proximal cortical bone layer after the drill tip has drilled through the proximal cortical bone layer so as to avoid stripping the threads formed in the bone layer. A method of installation is also disclosed.

An anchor fastener is described. The anchor fastener includes a head, a generally cylindrical shaft extending from the head, a base at a distal end of the shaft, and at least one frangible portion configured to frangibly connect the shaft to the base. The shaft includes a helical thread that extends along an outer surface of the shaft towards the distal end of the shaft. The frangible portions are separable from the base and the shaft under application of a force to the shaft. The base includes a distal surface and an engagement portion configured to engage an object to be anchored to a mounting surface and configured to hold the anchor fastener to the object before installation of the shaft through the object and into the mounting surface. The base includes a thread guide configured to support the helical thread during installation of the shaft.

A cold formed anchor for use in an insulated cavity wall includes a unitary body formed with a driver portion and having large and small diameter portions. The driver portion may be formed with structure for connecting a veneer tie to the anchor. A method of making the cold formed anchor includes cold forming a driver portion and a reduced diameter portion from a blank.

A self-drilling screw, particularly for use in a security screen employing leveraged clamping. The self-drilling screw comprises a head and a shank. A drill bit is formed at one end of the shank away from the head with a thread extending along the full length of the shank, including the drill bit. The thread on the drill bit increases holding strength.

A cement board screw a high thread that begins on the tapered end, extends onto the shank and terminates at a first axial location along the shank. The high thread defines a high peripheral edge, where a leading flank and a trailing flank meet at the high peripheral edge and together define a high thread angle that is between about thirty degrees and about fifty-five degrees. A low thread begins on the tapered end, extends onto the shank and terminates substantially at the first axial location along the shank such that an axial length of the low thread is substantially the same as and contiguous with an axial length of the high thread. The low thread includes a leading flank and a trailing flank that meet at a low peripheral edge and together define a low thread angle that is between about fifty degrees and about seventy degrees.

The invention provides a self-drilling screw structure and a manufacturing method thereof, wherein the manufacturing method includes: providing screw body, forming drill tail screw rod section, forming concave neck portion, forming drill tail cutting edge and forming thread. The self-drilling screw structure including a screw head portion and a screw rod portion, the screw rod portion is sequentially provided with a threaded screw rod section, a drill tail screw rod section and a drill bit screw rod section, the drill tail screw rod section has a rod diameter of drill tail, a plurality of drill tail cutting edges and a plurality of drill tail chip discharge grooves, the drill bit screw rod section is provided with a concave neck portion, and the drill bit screw rod section is protruded to form a plurality of drill bit cutting edges and the plurality of drill bit chip discharge grooves.