Of all the different Jig assemblies. This is the first one that I have seen that. Works off of the outside of the frame.
Look at it again Jim, the stop blocks (gauging) are on the inside of the end bars. That was not a issue. The issue was the rabbit in both the top and the bottom of the end bars was not centered the same between lots. For hand assembly this doesn't matter but when you automate something you have to control the gauging. In other words every lot must be the same and there is no reason it can't be. It doesn't cost the supplier any more to make it the same it is just that it doesn't matter to hand assemble so they don't bother.
A large manufacture of frames could take this concept and totally automate it if they had the volume to support the cost of automation.
All I did is cobble up a prototype out of wood. The concept is sound.