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Hardlock

Hardlock

 The primary reason for bolts breaking is a drop from the initial tightening strength (axial force) of the screw, leading to a shortened life span and metal fatigue/breakage. That is to say that a low-cycle fatigue of the bolt is induced, which leads to failure. There are many products in the world that can prevent screws from falling out, but none that prevent them from becoming loose. At the time, there were no self-locking components that could prevent loss in the axial force.
We then focused on the idea of completely eliminating play in screws. Our initial manufacturing concept was a single lock nut that could be produced as inexpensively as possible. No matter how much we brainstormed, however, our assumptions and preconceptions blocked us from thinking outside the envelope because of our initial conditions and focus on the preventing screws from coming out.