Abstract: The shank of a self tapping screw has a thread forming section, a threaded section, and a reduced diameter section interconnecting the forming and threaded sections. The thread forming section forms internal threads into a known thread form that has a wedge ramp at its root. The threaded section comprises threads of standard form having the same pitch as the thread forming section. The reduced diameter section is slightly longer than an integer multiple of the pitch so that the threaded section is backset slightly from the forming section.

Abstract: A mine bolt formed of continuous fiber reinforced pultruded rod-like reinforcing element is disclosed. This rod-like element includes at least one helical groove and/or protrusion along its length, with the continuous reinforcing fibers in the protrusions or surrounding grooves generally conforming to the helical pattern of the outer surface of the rod. The bolts formed by the instant invention also have utility in reinforcing such structures as mine roofs or concrete. The bolt of the instant invention comprises the above helically grooved rod fitted with an end cap that fits the helical turns of the grooved rod. The end cap may also serve as the mine roof plate.