||05-28-2013 12:40 AM
For a much better explaination that I can give, check out "The Razor Edge Book of Sharpening" for a good discussion on the theory and technique of putting a multi-bevel edge on a knife.
My exact method varies according to the original thickness of the blade, and the angles of the existing bevel(s). However, here's how I usually start.
It will be almost impossible to duplicate the original bevel of most factory edges. Sharpening will involve some minor re-profiling of the blade. Therefore the first sharpening will be the most involved; subsequent touch-ups will take much less effort.
Secure the blade into the clamp (pay attention to the clamp's position -- that is, where the front edge of the clamp is positioned between the edge and the top of the blade. Be consistent with where you clamp, as different positions can slightly change the angle of the grind).
I usually use the second hole from the bottom for my primary bevel (once again, it depends on the individual knife). I generally start out with the medium stone, and make four or five strokes. Then I look and see where the metal is being removed. If this angle goes along with the existing bevel, fine, but usually I am removing metal from the "shoulder" of the existing bevel. If there is a lot of metal to remove, I start out with the course stone, when I am approaching getting a flat "V" bevel, I switch to a medium grit, then fine. With each stone I do about 15-20 strokes on a side, then flip the clamp over and do the same on the other side, then repeat as necessary.
When I have a thin "V" on the edge, put the secondary bevel on by I increasing the angle of the bevel by raising the guide rods one hole (using the third hold from the bottom). I start out with the "fine" grit until I feel a slight burr on the edge. I strop the blade on a piece of leather (I have a couple of razor strops, but the back of a wide leather belt will work) to remove the burr. I then use the ultra fine stone to polish the edge, then strop again.
Others will differ in their techniques, but this is what works for me.