I built this internal resonator banjo 20 years ago…actually built two. Keeping the other.
The outer rim is 12”, inner rim is 7.5”. 25.5 scale length. 1.25” wide at the nut. Banjo has a rolled brass tone hoop. The bridging material between the rims is a product called garolite, used for circuit boards. This stuff is almost indestructible 1/8” thick. The purpose of an internal resonator is to give a more rounded less spikey sound.
Non-adjustable carbon fiber truss rod, Clawhammer banjos don’t need adjustable truss rods.
You can see I have a PNW inlay them going here.
As you can see I added a decorative lamination to the back of the neck. I used the same red under the fingerboard. I’ve used the same red under most of the fingerboards on my banjos.
This is not my first banjo. I’ve built/sold several. You’ll have a hard time finding a nicer banjo for the money.