I think you would waste a lot of blade material by milling. The problem
that I have is that the tips of the blades wear away faster than the rest of
the cutting surface. So one straight cut won't do it. I have 2 old Cub
Cadets with 3 blades each to sharpen. I simply use an old 6" bench grinder.
That way, I can sharpen the worn tip by following the worn edge by eye.
BTW, if I am feeling particularly cheap, I heat the tip and forge material
from the back side of the tip toward the front to give me an extra year or
two of use--- just like they used to do to "sharpen" a plow share.

Pete Stanaitis
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