The Ridgewing guitar body frames each possess a pattern of 13 M3 threaded brass inserts around their outer perimeter for attaching arbitrary “body inserts”, which is a generic term for anything that connects the bridge to the guitar body.  Carbon fiber grills were the original body inserts, but it soon proved irresistible to experiment with other types of inserts – solid wood planks, rosewood and spruce veneers mimicking traditional guitar construction, solid aluminum grills, etc. Whatever came into your head that day, each design using some subset of the available attachment holes.  By holding things together with a large pattern of screws, a number of these can be stripped, out-of-position, loose, or just missing, and it doesn’t matter. Just keep playing. The Ridgewing is intentionally what engineers call a “fault-tolerant” design.

If you make your own body frames, you will need to get the hole pattern put in around the back side of the outer perimeter. To do this on our prototype instruments, this Plexiglas drill guide was made using a basic band saw and hand drill. The hole pattern was printed off and taped onto the Plexiglas blanks, and the hole centers were marked by hand with an awl and then drilled through. The upper bout hole patterns required their own separate islands held in proper alignment with bolted-on “bridges”, so the entire hole pattern for both sides could be laid in place at the same time. Starter holes were then made in the frames using a hand drill at each hole in the Plexiglas pattern. In the final step, the jig was removed and final holes were hand-drilled for the M3 threaded brass expansion inserts.

If you are a machinist, I expect you are cringing at the thought of using raw Plexiglas for a drill guide, but it works well enough, which is what matters most. Taking fault-tolerance further, the hole pattern for body inserts can all be a little off, the bridge attachment to the body inserts can be a little off, just about everything can be a little of, but it is OK. At the end, when you finally string this animal  up, the string tension pulls all of the various components into rigid alignment, similar to how a new guitar string has to be tugged a few times to get all the slack out before it can be tuned precisely. Even if the final configuration of all the cobbled together components ends up being a little crooked, the three micrometer set screws on the hard points where the neck and body meet can be dialed in with extraordinary precision to get the neck alignment, intonation and action just right.