[TheForge] Re: Oregon fusion blades

[Mike Spencer]

PF wrote:

> ...or maybe, like case hardened knives the harder surface would then
> be self sharpening.

I have this vague recollection of seeing something about a system
where the sharpening process hardened the workpiece at the edge.  Say
you use air-hardening steel for a blade and heat-treat the piece for
maximum toughness.  Then if you (re)sharpen it with a power tool with
just the right grit at just the right speed, you'll bring the edge to
the critical temp and as it air-cools, it will harden. Just at the
very edge where the temp got high enough.

Obviously not for collector knives or luthier's chisels but for mower
blades, pulpwood shredders and such industrial stuff, it might be a
good trick.

I suppose to get the "just right", you'd need a mechanized grinder.
Just whacking it by hand with the angle grinder or flap wheel would
give unpredictable results unless the metallurgy wonks discovered a
very forgiving alloy.

Digression: after seeing what *real* sharpening means, watching a guy
in a paper mill sharpen a 10' paper-shear blade and watching techs in
a hospital research lab sharpen microtome blades, I just sharpen my
pocket knife with a smooth file.  Perfection is just out of my
reach. :-)


- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^