Field Sharpening
 

Maybe you guys can help me. How do you field sharpen your knives? What problems do you have? This is not a trick question because you guys are always surprising me with how much you do well. Reaper has already surprised me with a couple field expedient sharpening tricks I'd never heard of. I'm wondering what else I'm missing. Many Thanks, Bill

I carry a small whetstone and a small ceramic rod. Use the whetstone for more extensive work, the ceramic rod to dress an edge.

I have a diamond dust butterfly stone...fine on one side/ dress on the other...
For stuff that is really bad off...a swift river rock with water first has set me in a pinch - then finishing with some CLP, but I have never used this on my "Good Knife"...only a USN issue MK5 and the Survival vest Issue Knife.

Eagle

I am the worse knife sharpener in the world. I usually give mine to somebody that knows what they are doing in exchange for free medical care or something. I wish I could learn how to do it.

Cleaner, Lubricant, Protectant...it's "weapons windex"

Eagle

NDD, I've always said knifemaking is a genetic defect so your in good shape. Reason for my wanting all the response possible on this question is to see if what I know may be valuable to the Quiet Profesionals. My intention is to both write and illustrate a short piece on field sharpening. Goal is to make it useful to as many guys as possible. This will NOT be "how to bench sharpen in a well appointed custom knife making shop". This will be how to sit on the cold wet ground and make a knife that has seen some hard use cut again with stuff that's light enough to be in the pack when needed. Please guys, do not hesitate to jump in. This isn't a test and no judgement is being made. Remember, knifemaking is a genetic defect...and you all evolved past it.

CLP
 

Eagle, Thanks for CLP. I shouldn't forget that.

Okay, guess I will chime in here with my .02.

At home I have a Spyderco Tri-Angle sharpener and a DMT angle sharpener, along with files, a bench grinder, and all of my field sharpening gear.

For the field, I take a pair of DMT Duo-Fold double sided diamond sticks, and a DMT diamond rod for sharpening serrations. I drop the Duo-Fold, or a soft Arkansas stone into the outside pouch of a knife sheath. A machete or an axe really needs a file for the field.

For field expedient use, any flat abrasive surface harder than the steel works, albeit some better than others. Concrete works well in a pinch, as will hardened steel, certain bricks, or even the top of a vehicle window. I have stropped knives and razors on leather belts or the palm of my hand.

As I am sure Mr. Harsey will tell you, sharpening is an effort to remove metal from the edge of a blade to reshape it to a certain angle. Different blades and cutting applications require different angles. IIRC, the desired angles are usually from 35 degrees (blunt chopping tools) to 15 degrees or so (shaving razors). All other factors being equal, the thinner the angle, the quicker it will go away and need sharpening. Some tools have a double bevel on the edge, and some very dull ones can be best sharpened by taking an angle, then trimming it down to a lesser angle. If the blade was sharp on both sides, be sure to sharpen both sides equally in alternating patterns, or you will get a one sided or wire edge which will quickly come off and leave the knife dull again. Some knives are flat on one side and beveled on the other, like a chisel, and require sharpening only on the beveled side.

The harder the steel, the longer it will take to sharpen, and the longer the tool will hold its edge. The worst case is a hard steel tool with a very dull blunted edge being resharpened hair popping sharp. This can be a laborious process. It almost always takes less time to stop and keep the blade relatively sharp than to let it get extremely dull and try to resharpen it then.

And as Forest Gump says, "That's all I have to say about that" Hope that passes on what little I know about the subject and meets Mr. Harsey's intent.

TR

I have a DMT single sided, but I've never tried to use it.

I always had a spyderco ceramic double sided stone taped in it's sheath to my scabbard. Everyone who borrowed it said it worked awesome....I wouldn't know, I sharpen like NDD. :rolleyes:

NDD, I ended up getting a Lansky knife sharpener...that's the ONLY thing I can sharpen a knife with.

I like the spyderco ceramic cuz it doesn't load up that quickly and you can use spit as alubricant. Cleaned up really fast with a toothbrush and some soap.

Sir Reaper, Thanks! That's right on track, you've done this before haven't you? The reason I was thinking about "how to sharpen" was that I've noticed we are now several generations "off the farm and out of the woods" so to speak. I meet young guys now who never had their dad show them how to sharpen. I'll let out more as we go along, have any of you guys watched the ESPN, Stihl Timber Sports? Noticed any chopping with an axe? More on this to come and it has to do with field sharpening.

NOTE: Sharpening knives is dangerous and should not be attempted without adequate professional training and safety gear. Avoid cutting yourself, or others, as well as treasured items. Knives may inflict serious injuries, even when dull. Attempt sharpening at your own risk.

My technique would be to decide what a good angle would be for the knife and look at the gap between the rear of the blade and the stone. Try to maintain the same gap (angle) the entire time. Put the stone on a flat surface or if large enough, in your weak hand. Your thigh will do, if you are experienced and have nowhere else,, and have plenty of whole blood handy. While holding it at that angle and the base of the knife at the near edge of the stone, push the knife away from you (like you are trying to slice a wedge from the stone) while simultaneously sliding it so that the entire blade gets sharpened all the way to the tip. Reverse the blade to the other side and pull it back towards you at the same angle, being careful not to slice yourself in the process. Repeat as needed. If the stone loses its abrasiveness due to steel buildup, stop and wash it with liquid detergent. If you have two different grits, and the knife does not respond quickly to the finest, go back to start with the coarsest. Depending on the knife, the steel, the desired edge, and the cutting ability of the stone, this can take anywhere from a couple of minutes to an hour.

Looking forward to Mr. Harsey, Jr. telling me the correct way and learning something in the process. That is just the way my Dad taught me.

TR

Hey, unsolicited plug here.

I stopped by the DMT booth at the SHOT Show and the owner said that they receive thousands of requests every year for sharpening gear from guys who are deployed.

They have gone as far as adopting units and sending them care packages and sharpeners for free.

If you are passing on goodie lists to civilian support groups, you might add sharpeners like the DMT to the list, it appears that while every soldier has his Jimmy Lile Rambo knife, few thought to bring sharpeners. The Duo-folds are particularly handy.

Hey, NDD, wanna tell your One Eyed Nail story now?

TR

Reaper,
I've never before seen a warning for sharpening. I should post that in the shop here and read it once in a while. I've also never heard of balancing the stone on your thigh before. Like I said, this is where I get surprised, often. Ok now, ARE YOU NUTS? I'm going out in the shop to try that right away. Mishandling of edged tools around here over the years has resulted in stitches, couple trips to the ER and one scheduled surgery. Do as I say, not as I do.

Edited to add years later:
Of course TR is nuts, at a very high level of function. There are more here like him.

Field Sharpening is about getting it done in the field with minimum equipment. I am now going to look at this thread and for reasons of clarity may edit some of my writing as needed.

Somebody must have deleted it, I can't find it.

All I can tell you is that it is about 18% gray in color, it is small (about 3" long by 1" wide) and I work both knife and stone (yeah, I know, not a good technique, but I've always been one of those people who can put an edge on anything - learned in the boyscouts and found it easy).

Greenhat, I wouldn't dream of tampering with what is working. I may have to see the video someday...Sounds like you have a fairly common, good, small stone. That said, you may not easily find the quality of stone you have on the store shelf, don't lose it. Bill

LOL
Mr. Harsey,
Greenhat is what is known in the trade as a FOG. He probably has the stone tied to some part of his anatomy with a piece of green 550 cord.

I have always used a diamond rod about 4 inches long. Hasen't failed me yet. I was even able to put an edge on a splitting maul, not razor sharp but sharp enough to shave the hair on your arm. It took me about 3 hours but I was board as hell. I can't remember the name of the manufactor but I will post some pictures in a few.

Not Reaper quality but you get the idea

Smokin Joe, Those work good. I use the small flat plastic handled diamond sharpeners all the time around here on the bench and in the field. For bench work I can chamfer edges of hardened steel, touch up carbide milling cutters, drill bits and other small jobs by hand. More on that to follow.

On the ceramics, soak them in Clorox or scrub them with a Scotchbrite Pad or toothbrush and Chlorine Scouring Powder (Comet) to clean the metal from the pores. I also found that a plastic bag of clorox suspended in an ultrasonic cleaner really expedited the process.

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!

Re: How I Field Sharpen a knife, PART ONE
 

You see, I learn something new every day.

Thank you Mr. Harsey! Great input to a great thread.

TR

I was biting my lip, thanks Reaper. Just so I have it very clear, you push, then pull without turning the blade over (on the same edge)? Seems that would certainly help maintain the angle. It will also make the Emerson a snap, since the edge is one-sided sort of.

If Mr Harsey made a knife sharpening video I would buy it, I havent got a clue what Im doing and it would probably help me a lot to actually see it being done properly.

I'm in the same boat as Ktek.

Are the lansky sharpeners necessarily bad? It's the only thing I can sharpen a knife with.

My first knife was a Camillus Mk2 KBAR that I got from a SEAL that used it in Vietnam. I did more to ruin that knife with my attempts at sharpening it then anything else. :rolleyes: It's crazy how much metal I took off that thing, and all I did was make it as dull as a butterknife.

FIELD SHARPENING-IN THE FIELD
 

I just remembered, some of you guys pride yourself on being kinda resourceful.
This is a good thing however when I mentioned kerosene for the sharpening stone, I meant plain old lamp oil kerosene. This doesn't mean that I recommend you use the stuff from both the fixed and rotor winged fuel oil dispensers you may be in proximity of.
This stuff has more volatile organic compounds added and is probably not good to breath if you don't have to.


FOR FIELD SHARPENING I change gears pretty fast. I to use a different approach than in the shop to get the same result, much as many of you already do. I use the now common diamond sharpeners that are small and lightweight.
Here is how I sharpen when away from the shop.

Hold the knife stationary and move the sharpening stone. Seated is best so I can brace my knife holding arm on a leg. Do not stick knife in leg.

I work the edge of the knife with the diamond stone like I am using a file. The important step here is to look and see what the stone is doing on the edge.

Your sharpening stone usually makes a slightly brighter fresh mark on the edge when you start. This is when you make the adjustments by feel to set up the angle you want to sharpen at.

You can see where your sharpening while your working. At the bench we have to stop, take the knife off the stone and turn it over to see what was done. Advantage, Field Sharpening.

When sharpening you have to keep the same angle to get a knife sharp. This means doing the same thing until it's done, not changing the angle of stone until it sharpens the edge.

This is why thicker knives are harder to sharpen than thin knives- there is more steel to remove.

NousDefionsDoc,
You got it, I push and pull the blade a number of times on one side only, then turn the knife over and do the other side. This gets a lot of work done fast. I have to be smart enough to watch and feel what I'm doing so I don't do too much.
WOOBIE MASTER-
Lansky's are great, some of the sharpest edges I've ever seen customers do are with these. you could do surgical instruments with them if you could get the jig clamped on. I have one around here somewhere but it's too slow for me to set up and use and seems hard to do big blades with.
The reason I'm talking about hand held diamond stones for "field" use is they are very small and light, and don't care how hard the steel is.

If possible, carry at least Medium and Fine Diamond "stick". Using the Medium will save time by getting more done faster, then finish with the Fine. For hard work, you have a using edge using just the Medium.

Take for example the steel CPM S-30V, it has enough vanadium to form vanadium carbides. These vanadium carbides are harder than the aluminum oxide used to make sharpening stones but are valuable in that they add measurably to the edge holding when cutting tough materials.

Chris Reeve and I focused the heat treat on the Yarborough knife for maximum toughness with good edge holding. This knife is produced from the CPM S-30V.
This way we can sharpen the Yarborough knife on a normal stone and still have the edge holding abrasive resistance gained with the vanadium carbides.

I just tried your field technique on my Leatherman blade with the DMT pocket butterfly thing. I actually sharpened my knife! I will continue to practice (I have an old Gerber Mark II that has never been sharpened) before I start thinking I have it down, but you might have just achieved a miracle!

Thanks so much.

Announcer - "Tired of blistering your hands trying to cut tape with a dull knife? Think you're the only 43 year-old medic that can't sharpen a knife better than your kid? Been stabbed by Gs with more knives than you've managed to sharpen? Call the Bill Harsey Distance Learning Center and ask for 'Knife Sharpening for Dummies'! Call now! Call now!"

A testimonial from a satisfied student:
"Now I don't have to be embarrassed in front of my friends by having to saw on a piece of 550 cord to cut it. Thanks to the Bill Harsey Knife Sharpening School for Dummies, I can make people believe I actually know what I'm doing!"

LOL

Thanks!!!!!!! That just made my whole year. Bill

Thanks Bill.


I actually carried small medic scissors in my gear to avoid the embarrassment of trying to saw through stuff with a dull blade.

Prolly why I like spydercos so much!! :p

Lol NDD, that endorsement was priceless!:D

Bill,

When you say the wire edge...do you mean were the edge has rolled over or is burred?

No wonder I can't use a sharpening stone to save my life.

I always thought I had a piece of crap stone, also why I always used a diamond stone.

I always used a standard stone with a drop of CLP (A.K.A. break free) and circle montion starting from hilt moving to tip. Then flip the blade over and move from tip to hilt, but I could never get a good edge until I used a diamond stone.

Thanks Sir. I just did all my wife's Henckel kitchen knives. I was much more successful at keeping a constant angle with your described forward/backward without switching sides of the blade technique. Old dad never taught me I could do it that way back in the day...

I was knife sharpening disfunctional as well. I had to buy the lansky diamond kit because of it.

Great thread.

This is a great thread. I need to do my kitchen knives.

Mr. Harsey,

How do I sharpen a partially serated edge in the field?

Jawbreaker Sir, Great job sharpening! Nothing wrong with the Lansky, it's an awesome rig. You guys are making me proud because your going out and trying. My usual advice to folks who want to try a new way to sharpen is, start with your least favorite knives first, dig deep in the kitchen drawer and you'll find something. Sharpening is a learned skill and you'll just get better each time you do it again. I sharpen standing in the same place at the same bench with the same stone. Judging blade angle becomes natural because I don't have to adjust for other factors. Bill

To: Ird
 

Dear lrd, You asked a great question, How to sharpen a partially serrated blade in the field.
First please know I'll answer this question and you will get a very serviceable sharp edge back but it won't be quite as acutely sharp as most of them come from the factory but it will have better edge endurance.
Spyderco is the modern re-inventor of the serrated blade. I like those people and they deserve credit for the innovations they brought to the worlds knife industry.
I get a number of Spyderco serrations in my shop for sharpening.

FIRST,
The advantages of the serrated edge is it's acute sharpness and aggressive cutting due to it's extremely acute bevel angle.
Also why I think they are so popular is that when real hard stuff is cut with it and the edge is abused, it is dulled in a selective manner leaving some part of the serrations that can still cut.
The gullets (valleys) between points stay sharp because they are protected by the points which usually dull first. This is what makes this type of edge seem to stay sharp longer. Spyderco does very good work.

Sharpening Serrations- Most serrations are ground in from one side only.
The "Yarborough" knife we make for the men of the Untied States Army Special Forces is a different kind of serration. This is a Chisel Point serration, this designed to cut very tough materials and be resharpened perfectly using the same angle as the main edge and at the same time. Just ignore the serrations and sharpen the entire length of the blade.
The reason I bring this up is what I'm about to describe applies more to the Spyderco type serrations.

With apologies to Sal Glesser, founder of Spyderco:
I sharpen the Spyderco type here in the shop just like you will do in the field. I turn the knife over to the side opposite the serrations being ground in from and establish a fine bevel on the back of the serration with a hand held stone.

Match this bevel to your main edge and it should work great. This will resharpen both the points and gullets of that edge. It will also be a stronger edge thus holding up to more hard work better. I stated before they may not be factory sharp but you'll be surprised how sharp they come back up. Some of you are good at going in the front of the serrated grind with shaped stones and matching the initial grind plunge. I don't have that kind of patience. Does this help? Please advise. Bill

Great thread, great information. Thank you Mr Harsey:

Terry

Outstanding! :D