Hi KCSteve
our system for sharpening :(
The way we were taught to shape a flat graver was to grind a curve on the whole bottom of the grave with a grinding wheel then emery papers, trying to keep it flat with a gentle curve or belly, then the face was cut at 45, by hand on a stone. this gave you a heel along the whole length of the graver, so in theory you would never need to sharpen it again, you only have to sharpen the face occasionally.
In practice most of us got the angle wrong, with too high or low lift each with its own problems, especially for a beginner who doesn't know about such things.
Our teacher didn't believe just a flat graver with a small heel would work, and believed a square graver would not work as well, one of the advantages of being an older student, I just tried it any way. All the later plates were engraved with these newer engravers
Still I treated it all as a learning exercise
Paul