Precision torque control positive lock nut

A combination positive locking and prevailing torque fastener system, comprising:

• a fastener nut having a nut proximal end and a nut distal end, a nut bore extending from the nut proximal end into the fastener nut and defining a nut bore axis, a plurality of nut bore threads on at least a portion of the nut bore, and a nut exterior surface having a plurality of nut serrations parallel to the bore axis;
• a helical wire insert formed to create a plurality of insert external threads and a plurality of insert internal threads, wherein a portion of the insert external threads mate with a portion of the nut bore threads in a portion of the nut bore and engage the fastener nut, and the helical wire insert has a tensile strength of at least 200,000 psi and a Rockwell C hardness of 43-50 RWC;
• a nut cap having a cap proximal end and a cap distal end, a nut cap bore extending from the cap proximal end and defining a nut cap bore axis and a nut cap bore interior surface having a plurality of nut cap serrations parallel to the cap bore axis, a nut cap exterior surface having a tool interface portion, and at least four notches extending from the cap distal end toward the cap proximal end, wherein the nut cap bore is sized to receive at least a portion of the fastener nut;
• a cap retainer having a retainer proximal end and a retainer distal end, whereby the cap retainer receives at least a portion of the fastener nut and engages the nut cap;
• a shaft having a cross bore and a plurality of shaft threads that mate with a portion of the insert internal threads such that an insertion torque is required to create relative movement between the shaft threads and the insert internal threads in a first direction, and a removal torque is required to create relative movement between the shaft threads and the insert internal threads in a second direction opposite the first direction;
• and
• a pin sized to pass through the cross bore and at least two notches;
• wherein the nut cap is longitudinally movable from an engaged position to a disengaged position such that in the engaged position the plurality of nut cap serrations cooperate with the plurality of nut serrations so that the fastener nut and the nut cap are rotationally locked, and in the disengaged position the plurality of nut cap serrations are separated from the plurality of nut cap serrations so that the nut cap rotates independent of the fastener nut to align at least two notches with the cross bore and allow the pin to pass through the cross bore and the two notches to thereby prevent relative movement of the fastener nut and the shaft;
• and
• wherein the cap retainer prevents the fastener nut from exiting the retainer proximal end, and the cap retainer engages the nut cap to (a) allow longitudinal movement from the engaged position to the disengaged position, (b) allow rotation of the nut cap relative to the cap retainer, and (c) secure the nut cap to the cap retainer and thereby confine the fastener nut.