I made a frame for my Mom last Christmas out of sapele mahogany using splined miters. The miters look like they were glued yesterday, and the best part is - no fasteners!
Splines were 3/16" thick, 1 1/2" wide and cut to protrude from either end of the joint. After the glue cured I cut them flush with a dovetail saw.
invented this "nail" about 80 years ago or so. My mom told me about them and we had some in a box. That was 60 years ago. I wish I still had some to mess around with. It seems like a great idea. Here's the site: http://clampnailco.com/
Professional frame shops use V nails. It's not always possible to use splines, half laps or keys unless you are just making flat board frames. This supplier has hardened V nails that can be driven with a hammer. http://www.grignonsart.com/Learning_...e%20frames.htm