So my father-in-law has played guitar off and on since his twenties and he's now 65. He's also has woodworking for a hobby so he decided to take the plunge and build his own guitars.
He started with a 12 string somewhat Rickenbacker-ish semi-hollow body. He bought the neck and hardware but build the body from scratch out of mahogany and maple I think.
I know these aren't really "metal" guitars but thought you may enjoy anyway.
On his second one, he made his own thin neck laminating white korina with mahogany, a book matched mahogany body with a white korina top, and tung oil finished. It plays like a dream.
He even made his own coffin case.