Well I just bought a Spyderco Native Chief in REX 45. I guess I'll send it out to be re sharpened, requires diamond stones. I'm not spending $56 a pop for diamond stones for my edge pro!
Bench grinder with wire brushes instead of stones, one brush stiff the other softer. Give it an all over brushing then attach some buffing wheels and work over using progressively finer compounds. Should clean up pretty well. Then work on some scales.