font-awesome-animation/scss/wrench.scss

$faa-wrench-speed: 2.5s;
@keyframes wrench {
  0% {
    transform: rotate(-12deg);
  }
  8% {
    transform: rotate(12deg);
  }
  10%, 28%, 30%, 48%, 50%, 68% {
    transform: rotate(24deg);
  }
  18%, 20%, 38%, 40%, 58%, 60% {
    transform: rotate(-24deg);
  }
  75%,100% {
    transform: rotate(0deg);
  }
}
.faa-wrench.animated,
.faa-wrench.animated-hover:hover,
.faa-parent.animated-hover:hover > .faa-wrench {
  animation: wrench $faa-wrench-speed ease infinite;
  transform-origin-x: 90%;
  transform-origin-y: 35%;
  transform-origin-z: initial;
}
.faa-wrench.animated.faa-fast,
.faa-wrench.animated-hover.faa-fast:hover,
.faa-parent.animated-hover:hover > .faa-wrench.faa-fast {
  animation: wrench ($faa-wrench-speed * $faa-speed-coeff-fast) ease infinite;
}
.faa-wrench.animated.faa-slow,
.faa-wrench.animated-hover.faa-slow:hover,
.faa-parent.animated-hover:hover > .faa-wrench.faa-slow {
  animation: wrench ($faa-wrench-speed * $faa-speed-coeff-slow) ease infinite;
}