MIMF

I have been working on a design for a one piece aluminum bracing system for the back of a dreadnaught style guitar. Does anyone know of anything done before in this area of design/building? My thoughts are using a 3D drawing to print on a 3D printer. Basically it would be a forward X bracing style for a starter and then a Kasha style similar to the work by Steve Klein. Someone must have made a bracing system that is rigid one piece. Maybe back after WW2.

I haven't heard of metal bracing but there was a company making a one piece injection molded plastic frame for acoustic guitar body. The frame became the binding and wood panels were installed on the frame. I wasn't impressed with the sound the guitars produced but once you have a system all you need to do is improve on it until it is a great product. Right?

I've never heard of a 3D printer that works with aluminium as a medium. I can think of a couple of ways it could be achieved, but it would be very expensive and not very practical.
I think what you should be looking into would be milling or casting.

Some additive manufacturing (3D printing) is being done with lasers and metal powders. So far I have heard of turbine blades for jet engines being made and used successfully. More power to anyone going that way. Just imagine orbiting robot printers printing a space station! It could happen.

Most 3D printers that are accessible to civilian mortals are using some form of plastic as the medium to form objects, though the future is coming soon.