Field Sharpening of Convex Edges

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campandtravel

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To start with, let me define what I mean by "field sharpening." I mean a method of sharpening that uses materials you will find in the field. *Not* a method that requires you to bring things with you into the field. That is still a dependency. A flat stone or work sharp can get lost or broken, leaving you with a dull knife. Plus it's extra weight to carry and if you spend any real time in the field you'll know that ounces matter. That might be find for weekend warriors, but someone who is in the field for months at a time would be in a bad situation.

So given those parameters, is there a good way to field maintain a convex edge? In my experience the answer is no and even my tommy has been flattened out a bit after field sharpening. Maybe I am missing something.
 
campandtravel said:
So given those parameters, is there a good way to field maintain a convex edge? In my experience the answer is no and even my tommy has been flattened out a bit after field sharpening. Maybe I am missing something.
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Just so I understand, are you saying that a Non-Convex edged knife can be "sharpened in the field" but a Convex edge knife can not?
If that is correct, could you tell me how you would sharpen a Non-Convex knife "in the field"?
 
I'm inclined to believe that if one knows or at least speculates they're going to be 'in the field' for months at a time, then one should rationally weigh the trade-offs between (a) carrying one or two small, lightweight hones, which will work FAR BETTER in maintaining any knife's edge, convex or not, or (b) not carrying anything to maintain the knife's edge and instead relying on pure luck in finding some rock or other implement which may or may not do an adequate job. Carrying the right tools for the task, especially when many of those right tools might only weigh a couple ounces, will buy a lot more peace of mind, when nothing else simply found in the field would get the job done. So much depends on where you happen to be when the need arises.

The vast majority of natural stones will only be marginally harder than most knives' basic steel composition (iron + carbon). And never mind supersteels with very hard carbide content, for which virtually nothing you'll find on the ground will be adequate to resharpen those. And the grain structure of many natural stones, depending on geologic regions where they might be found, won't often be suitable for sharpening anyway, being either too coarse or too irregular in grain size, or too blocky or too rounded in shape and therefore structurally incapable of cutting hardened steel. Just picking up a rock off the ground and sharpening away sounds exciting - but it's not usually going to work so well (if at all), depending on what steel is being sharpened and how damaged or dull the edge might be, before the sharpening attempt is made.

At the very least, if one is determined not to bring the right tools along, then selecting a much simpler and less hard steel for one's blade choice might improve the odds a bit of being able to resharpen it with some simple natural stone. Leave the high-wear steels at home, if you're not willing to also bring a good hone (and a spare) along.

The diamond hone pictured below weighs maybe an ounce and a half and will be capable of resharpening literally any blade you choose to take along. Sometimes the extra ounce or two of carried weight is well worth the trouble if viewed against the possibility of not being able to get the job done with anything just 'found' at hand, when you really need a solution.

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Obsessed with Edges said:
I'm inclined to believe that if one knows or at least speculates they're going to be 'in the field' for months at a time, then one should rationally weigh the trade-offs between (a) carrying one or two small, lightweight hones, which will work FAR BETTER in maintaining any knife's edge, convex or not, or (b) not carrying anything to maintain the knife's edge and instead relying on pure luck in finding some rock or other implement which may or may not do an adequate job. Carrying the right tools for the task, especially when many of those right tools might only weigh a couple ounces, will buy a lot more peace of mind, when otherwise nothing else simply 'found' in the field would get the job done.

The vast majority of natural stones will only be marginally harder than most knives' basic steel composition - and never mind supersteels with very hard carbide content, for which virtually nothing you'll find on the ground will be adequate to resharpening those. And the grain structure of many natural stones, depending on geologic regions where they might be found, won't often be suitable for sharpening anyway, being either too coarse or too irregular in grain size, or too blocky or too rounded in shape and therefore structurally incapable of cutting hardened steel. Just picking up a rock off the ground and sharpening away sounds exciting - but it's not usually going to work so well (if at all), depending on what steel is being sharpened and how damaged or dull the edge might be, before the sharpening attempt is made.

At the very least, if one is determined not to bring the right tools along, then selecting a much simpler and less hard steel for one's blade choice might improve the odds a bit of being able to resharpen it with some simple natural stone. Leave the high-wear steels at home, if you're not willing to also bring a good hone (and a spare) along.

The diamond hone pictured below weighs maybe an ounce and a half and will be capable of resharpening literally any blade you choose to take along. Sometimes the extra ounce or two of carried weight is well worth the trouble if viewed against the possibility of not being able to get the job done with anything just 'found' at hand, when you really need a solution.

71twjbYYS8L._AC_SX425_.jpg
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Nope... still way too heavy. And you could lose it. 😉😁
 
Or I could lose my knife. Problem solved. :cool:
I still think a pocket sharpener or two is the best way. Better than expecting sheer luck to provide at the right time and place instead.
A small piece of rouge on a leather belt will last forever also.
But as others wrote, a flat piece of stone is enough. It can be lapped with another stone if/as needed.
 
campandtravel said:
To start with, let me define what I mean by "field sharpening." I mean a method of sharpening that uses materials you will find in the field. *Not* a method that requires you to bring things with you into the field. That is still a dependency. A flat stone or work sharp can get lost or broken, leaving you with a dull knife. Plus it's extra weight to carry and if you spend any real time in the field you'll know that ounces matter. That might be find for weekend warriors, but someone who is in the field for months at a time would be in a bad situation.

So given those parameters, is there a good way to field maintain a convex edge? In my experience the answer is no and even my tommy has been flattened out a bit after field sharpening. Maybe I am missing something.
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Sure you are missing something.
Everywhere in the world that people have used steel tools they have found a way to sharpen them with what is available in their area.
A creek bed would be a good place to start for a suitable stone. Sand stone, slates, jasper and many more. Knife boards were used with sand for sharpening, wood ash or even some types fungus for stropping.
The possibility's are almost endless.

If you couldn't find a way to sharpen your knife in a survival type situation it might be best to slit your wrists before it gets dull.
 
AntDog said:
Rub some sand on your belt and strop away.
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That's a pretty good idea but not for someone who does a lot of extended hiking. I don't know any thru-hiker who uses a leather belt. Way too heavy, and not at all good when wet, which is the state of things when you're not baking.
KenHash said:
Just so I understand, are you saying that a Non-Convex edged knife can be "sharpened in the field" but a Convex edge knife can not?
If that is correct, could you tell me how you would sharpen a Non-Convex knife "in the field"?
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Well, there are different types of non-convex edges. A scandi grind is useless in the field based on my personal experience because you can't sharpen it (unless you want to create a secondary bevel).

For "normal" knives (sorry I don't know what grind that is) I just use a river stone.
Obsessed with Edges said:
then one should rationally weigh the trade-offs between (a) carrying one or two small, lightweight hones, which will work FAR BETTER in maintaining any knife's edge, convex or not, or (b) not carrying anything to maintain the knife's edge and instead relying on pure luck in finding some rock or other implement which may or may
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Right. I did that and came to the conclusion I did. You're trying to question the premise instead of answering. I am so glad this board has an Ignore feature.
Triple_D said:
What did you use on your past, extended trips, in the field?
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Kind of irrelevant since I have not brought a convex-ground tool before.
Alberta Ed said:
DMT Diafold. Use a trailing stroke for convex edges.
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You are answering a different question than the one I asked. Rude. I'm so glad this board has an Ignore feature.
 
Dunno if this addresses your question properly, but there’s a particular kind of sandstone I look for on Pacific coast beaches. It’s kinda medium gray and soft enough to be flattened with another stone. I bring promising specimens home and flatten them further with 400 grit wet/dry paper on my band saw table. The rounded edges get into the curve of a hawkbill nicely.

I sharpen convex edges with a trailing stroke, rotating my wrist slightly. Kinda weird motion, but you get used to it quickly. Or you can hold a steady angle on a dished out stone, starting at the middle. Use the Sharpie trick to see where the stroke is landing, adjust to suit.

Parker

PS: if you ignore those guys, you’ll miss out on some good shiite.
 
campandtravel said:
That's a pretty good idea but not for someone who does a lot of extended hiking. I don't know any thru-hiker who uses a leather belt. Way too heavy, and not at all good when wet, which is the state of things when you're not baking.

Well, there are different types of non-convex edges. A scandi grind is useless in the field based on my personal experience because you can't sharpen it (unless you want to create a secondary bevel).

For "normal" knives (sorry I don't know what grind that is) I just use a river stone.

Right. I did that and came to the conclusion I did. You're trying to question the premise instead of answering. I am so glad this board has an Ignore feature.

Kind of irrelevant since I have not brought a convex-ground tool before.

You are answering a different question than the one I asked. Rude. I'm so glad this board has an Ignore feature.
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Who said it had to be leather.

Stop being boneheaded and pack a DMT diafold. They’re light, and just try to break one. No sense in trying to form some contraption in the jungle because you’re scared your gear will weigh too much or break when the correct tool for the job weighs a couple of ounces and is damn tough.
 
If your concern is maintaining a convex edge specifically, perhaps you’re asking too much of your situation. I think you know that already though. Antdog’s belt-n-sand strop idea might be worth a shot.

Also your hunt for self-sufficiently is admirable, but what do you do when you bust or lose your knife in the woods, forge a new one from raw materials? Gotta draw the line somewhere. Come on… just take a dia card.

I’d bring some type of tool for sharpening. It doesn’t have to be much. I would pack a lighter, less robust knife if that’s what it took to carry some kind of sharpening method.
 
Split a piece of fine/smooth grade wood, try to flatten the wood further with a rock if possible, rub a bit of wet dirt on it, let it dry, and use trailing edge strokes.

A belt, as mentioned earlier, would work even better. Especially if you pre-loaded a portion with compound.

.
 
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If you deliberately leave a perfectly good hone at home because it's too heavy or you're worried about losing it...
...then search far & wide to find a suitable stone or other implement to sharpen with...
...And once you've found something to use, possibly putting considerable effort into flattening it and making it suitable for sharpening...
...Do you now leave behind the tool that you improvised, because it's too heavy?
...Or do you hold onto it, now carrying an improvised tool that's possibly heavier than what you left at home, and likely doesn't work as well as what you left at home?

These days, with better / harder / more wear-resistant steels being the norm, I'd still think it's better to take something you know will work with minimal effort. Then, if you do lose it for some reason, you do what's necessary to improvise while still accepting the possibility that it might not work so well. There's no good reason to deliberately handicap oneself from the get-go, for the sake of saving a few ounces or less of carried weight. It can be worthwhile to experiment with these things while out & about, while also knowing you have a proven backup solution in your pocket that works anytime & anywhere with any blade. But the improvised solution likely won't be a given, once you're forced into figuring it out for survival's sake.
 
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The entire idea of 'ounces matter' is about conserving your energy and not using it unnecessarily. So how many calories are you going to burn carrying a 3oz tool that's ideal for the job vs searching for and using an improvised tool to maintain your edge?

Bluntly, I think the entire premise of the question is an excellent example of being penny wise and dollar foolish. You're establishing a gain that likely only exists on paper and almost certainly results in a net loss.
 
If you're that into rocks find a flint and stone and knap yourself a new sharp edge when you need it. Then you don't even have to bring a knife. That's gonna save a few ounces right there.
 
From what I've gleaned over the years, a lot of hardcore ultralight hikers don't even carry a knife... So if you're unwilling to listen to any advice maybe that would work. You save the weight of a sharpener, a knife, AND the trouble of the search for suitable material along the way.
 
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