Guide to Honing and Sharpening
Four Reasons for Honing
on the picture to enlarge
from the Grinder
honing and stropping (microbevel almost invisible)
Re-texturing the ground edge. The coarse abrasives used in
a grinding wheel are necessary for the fast and cool removal of metal.
Fine abrasives would be (a) unproductively slow cutting and (b) would
rub more than they removed, causing heat build-up that ruins the tempered
hardness of a blade. But efficient, coarse cutting wheel does exact
a price. The large particles serrate the tool's working edge into
a weak (microscopic) saw-tooth texture: the strongest possible sharp
edge would be unified (i.e., linear and continuous), not chopped into
separate "teeth," unsupported by adjacent substance. We strengthen
the sharp edge by honing the bevel/edge entity on a series of ultra
fine-abrasive oilstones. Good honing reduces the peaks and valleys
to a virtual straight line, even viewed under very high magnification.
Removal of burr. As metal is ground to thin cross-section (i.e.,
sharpness) it does not form a neat triangular profile: the tissue-thin
edge and attached debris curl over into what is called the "burr"
or "wire." We must abrade or fatigue this microscopic "steel
wool," to expose the underlying solid edge, via the honing process.
This also straightens, burnishes and polishes the edge's component
front and back faces, hence the edge itself.
Second bevel. Honing at a raised angle (5 degrees or so) consolidates,
and strengthens the edge by forming a second (more obtuse) bevel.
This is an option. Old "carpenters'" style allowed a considerable
2nd bevel to accumulate before grinding anew - this is for rugged
work. An effective alternative is the now common micro bevel style
shown in this lesson.
The final, probably commonest reason for honing is simply to restore
an edge moderately dulled by normal use. Grinding is for major
alteration of edge and bevel. Honing is for everyday finessing.