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**Bill Harsey** · 02-29-2004, 14:41

My field experience comes from logging, hunting and fishing. All involve activities far from a dry comfortable shop and usually an edged tool is involved.
You guys get a lot farther from the shop than I do so here is PART ONE:- As a knifemaker I have long worked at testing various steels, heat treats and sharpening methods to arrive at what works best for my knife owners. I am not alone in this, much of this testing was with my peers and done in public in front of many in the knife industry. For several years I helped put on the OKCA Knife Steel Seminars each April in conjunction with the Oregon Knife Show and was a featured speaker. Knives get dull, that's a fact of life.
The best steels on this planet can be dulled by something. There is no such thing as a dull proof steel. We use the best steel we can get our hands on but edge work will still be needed at some point.

To understand how to sharpen in the field, let me try to explain how I sharpen under ideal conditions first.
At the bench in the shop I use a Norton two sided stone about 10 inches long. The fine side is Norton Fine India, about 320 mesh aluminum oxide and that's what I use the most. For game work this stone will put an edge on a knife that will both cut the best and last the longest. Under magnification this edge looks like a row of very fine saw teeth coming from each side.
There are many different kinds of sharp and not all of them are good for us. An example of "sharp but not good" is a fine polished true razor edge like on a scalpel. This edge has very high intial sharpness but gets dull very fast because there is no "tooth" to the edge like we get with the 320 mesh stone. This is diminished edge endurance due to structure from finish.
The first thing I do prior to sharpening is anchor the stone to the bench so it doesn't slide while sharpening. Next I find the WD-40 or even better, some kerosene. This is to keep the shavings of steel abraded from the knife from sticking to the stone.
If I have a dull knife, the edge, under the microscope may look smooth, worn, chipped, rolled over and just plain rounded off, depending on how the steel failed. All steel will fail under the right conditions.
As The Reaper said, we have to remove steel to re-establish two clean planes coming together from each side to form the sharpened bevels.
I use both my hands on the knife, one on the back of the blade for pressure. For double edge knives, this means pay extra careful attention or at least keep a stack of real good bandaids nearby.
I set up my angle and push as if I'm trying to take a shaving off the surface of the stone. I do not change angle for the backstroke and return the knife on the stone.
This is an abrasive process and unless we are sharpening straight razors on soft (fast sharpening) stones and strops, cutting on both the push and pull is ok. The key is keeping the same angle without having to relocate the edge for every stroke. When we have taken enough steel off the edge to bring the sharpening bevels back together from each side, this can be perceived by feeling for the "wire edge".
The "wire edge' is steel that is tough enough to not break free of the end of the blade but is no longer part of the solid edge. re-read this last sentence several times
You can feel this by rubbing your finger tip from the master bevel outward off the edge. Do this from each side and you may feel the burr from one side only.

How we remove this burr, or wire edge determines how sharp the knife starts out. Do it again
If you bend the burr back and forth until it breaks off this will make a series of little flat spots on the most outward part of the cutting edge and this is not as sharp as this knife can be!.
I remove the burr by barely increasing the sharpening angle ever so slightly (picking the spine of the blade a bit higher off the stone) and taking a light wispy stroke on the stone, alternating sides. Depending on the alloy of steel and the heat treat this may leave little strands of steel on the stone when the wire edge comes off. This edge should just shave hair and cut difficult materials aggressively.
Greenhat is doing the same thing when he uses the small ceramic stick to finish his knife. ON TO THE FIELD!

02-29-2004, 14:41	#23
Bill Harsey Bladesmith to the Quiet Professionals Join Date: Feb 2004 Location: Oregon, Land of the Silver Grey Sunsets Posts: 3,886	How I Field Sharpen a knife, PART ONE My field experience comes from logging, hunting and fishing. All involve activities far from a dry comfortable shop and usually an edged tool is involved. You guys get a lot farther from the shop than I do so here is PART ONE:- As a knifemaker I have long worked at testing various steels, heat treats and sharpening methods to arrive at what works best for my knife owners. I am not alone in this, much of this testing was with my peers and done in public in front of many in the knife industry. For several years I helped put on the OKCA Knife Steel Seminars each April in conjunction with the Oregon Knife Show and was a featured speaker. Knives get dull, that's a fact of life. The best steels on this planet can be dulled by something. There is no such thing as a dull proof steel. We use the best steel we can get our hands on but edge work will still be needed at some point. To understand how to sharpen in the field, let me try to explain how I sharpen under ideal conditions first. At the bench in the shop I use a Norton two sided stone about 10 inches long. The fine side is Norton Fine India, about 320 mesh aluminum oxide and that's what I use the most. For game work this stone will put an edge on a knife that will both cut the best and last the longest. Under magnification this edge looks like a row of very fine saw teeth coming from each side. There are many different kinds of sharp and not all of them are good for us. An example of "sharp but not good" is a fine polished true razor edge like on a scalpel. This edge has very high intial sharpness but gets dull very fast because there is no "tooth" to the edge like we get with the 320 mesh stone. This is diminished edge endurance due to structure from finish. The first thing I do prior to sharpening is anchor the stone to the bench so it doesn't slide while sharpening. Next I find the WD-40 or even better, some kerosene. This is to keep the shavings of steel abraded from the knife from sticking to the stone. If I have a dull knife, the edge, under the microscope may look smooth, worn, chipped, rolled over and just plain rounded off, depending on how the steel failed. All steel will fail under the right conditions. As The Reaper said, we have to remove steel to re-establish two clean planes coming together from each side to form the sharpened bevels. I use both my hands on the knife, one on the back of the blade for pressure. For double edge knives, this means pay extra careful attention or at least keep a stack of real good bandaids nearby. I set up my angle and push as if I'm trying to take a shaving off the surface of the stone. I do not change angle for the backstroke and return the knife on the stone. This is an abrasive process and unless we are sharpening straight razors on soft (fast sharpening) stones and strops, cutting on both the push and pull is ok. The key is keeping the same angle without having to relocate the edge for every stroke. When we have taken enough steel off the edge to bring the sharpening bevels back together from each side, this can be perceived by feeling for the "wire edge". The "wire edge' is steel that is tough enough to not break free of the end of the blade but is no longer part of the solid edge. re-read this last sentence several times You can feel this by rubbing your finger tip from the master bevel outward off the edge. Do this from each side and you may feel the burr from one side only. How we remove this burr, or wire edge determines how sharp the knife starts out. Do it again If you bend the burr back and forth until it breaks off this will make a series of little flat spots on the most outward part of the cutting edge and this is not as sharp as this knife can be!. I remove the burr by barely increasing the sharpening angle ever so slightly (picking the spine of the blade a bit higher off the stone) and taking a light wispy stroke on the stone, alternating sides. Depending on the alloy of steel and the heat treat this may leave little strands of steel on the stone when the wire edge comes off. This edge should just shave hair and cut difficult materials aggressively. Greenhat is doing the same thing when he uses the small ceramic stick to finish his knife. ON TO THE FIELD! Last edited by Bill Harsey; 12-04-2008 at 19:56.
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