The stainless steel frame-joining bracket is fitted into the inner face of the treble frame, where it presents three keyhole slots which in turn engage three SHSC screws on the opposed inner surface of the bass frame. The inner surface of the bracket behind each keyhole is sloped, so that after the head of each joining screw has entered its opposed frame keyhole, the two halves of the frame are slid against each other about a half inch, with the joining screw depths adjusted so that at the end of the half-inch excursion, the frames are locked tightly together.


This image shows a horizontal cross-section through the guitars body along the midline of the joining bracket and screws. The joining screws mounted in the bass frame are colored blue.

In this cross-section detail of the middle bracket, the various features can be seen. Threaded inserts for screws are shown in yellow and brown. The flathead machine screws holding the bracket in place are white, and the bracket itself is faintly blue. The cavity behind the keyhole is highlighted in light blue where the sloped tensioning surface can be seen. The joining screw is blue.  Its fine thread enables extremely precise adjustment for optimum joining force.

And then take away the guitar:

And then the full kit and caboodle.

This Ridgewing bracket is essentially identical to the bracket used in the Chrysalis guitar, as it proved to be an optimum design, except that the Ridgewing bracket was made with metric dimensions.

While this bracket does an excellent job of locking the two frames horizontally against each other, racking the neck horizontally can cause the joinery screws to slide longitudinally ever so slightly in their keyholes, causing the strings to not be centered on the neck.  To fix this, a separate "frame-lock" mechanism is added to the inner frames, locking them longitudinally.