I was recently camping with a CRKT MaChete, and sharpening was a pain in the butt. I carry a Diafold, and I can sharpen my knives easily when I'm in the woods. This convex ed ge was a pain. I'm not going to carry a mouse pad and sandpaper. Yes, it is a fantastic edge, but I will carry flat or hollow(which have never broken on me, contrary to popular opinion) edged blade from now on,which I have for 32 of my 44 years. Wanted to see if the hype was worth it.
Convex edges: Are they really practical?
- Thread starter J.Davey
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I freehand sharpen so convex edges are not hard for me to produce. It took some practice but I can maintain a convex edge with my pocket DC4 stone if it were needed (haven’t had to in the field since my knife edges tend to last a good while, but I could if I needed to in the field). As it stands I just restrop my knives when I get home with some green compound and get that baby back to shaving sharp. For me the convex edges just last so much longer. I really prefer them.
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What is it with this myth about maintaining a convex edge ‘in the field’ being something difficult to do?
As mentioned above, with a small stone such as a DC4 or Lansky Puck, it is inevitable that hand sharpening on anything other a zero Scandi grind will produce a somewhat convexed edge. For a convex geometry behind a convex edge, such as a wilderness axe, you can keep the blade stationary and move the stone over the edge; it also works with knives, of course.
I’m by no means an amazing sharpener, I don’t produce mirror polished edges, but this sort of basic maintenance is just that: basic.
As mentioned above, with a small stone such as a DC4 or Lansky Puck, it is inevitable that hand sharpening on anything other a zero Scandi grind will produce a somewhat convexed edge. For a convex geometry behind a convex edge, such as a wilderness axe, you can keep the blade stationary and move the stone over the edge; it also works with knives, of course.
I’m by no means an amazing sharpener, I don’t produce mirror polished edges, but this sort of basic maintenance is just that: basic.
I would prefer them, also! I'm just imagining a survival situation. I know it's implausible, butwe all seem to judge in tenths;"B.O.B", etc.
Every other edge , can be sharpened quickly on a flat stone, etc. I know about the crushed rock thing. Still seems like a time waster in a survive NOW situation.
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A convex edge can also be sharpened against a flat stone.
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I've invested a ton of money into a system that makes creating a very refined V edge quick and easy, so that's what I convert them all to. "In the field" though I always found a convex edge easier to maintain. As stated above, you can move the stone rather than the knife. Baryonyx sells a bunch of nice ones for that sort of duty. Long and slender seems to work best. It's just a different technique.
Yep. As you have noted the sharpeners that Fallkniven sells are flat stones.
But aren't you just re-profiling the edge to a flat grind? If you had started with a flat grind, you would have saved valuable time in a survival situation. Ya' know?
OK. Say you are in one of these survive now scenarios...whatever that means....and you, in this scenario hold your convex knife at the exact same angle on every stroke, all you have done is put a micro flat edge on your convex knife, and sharpened it.
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Any human hand doing freehand sharpening will end up with a slightly to very convex edge.
No. See above.
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No.
And no again.
You can maintain and sharpen a convex edge and even one supported by a convex grind with a flat stone. It is not rocket surgery.
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If you use a technique that produced a V grind, yes, but you can also create a convex edge with a flat stone. Think of it like the facets on a gemstone. A bunch of flat surfaces at varying angles can create a curve. You just blend them together. It's actually a lot more forgiving when you get the hang of it. All of my large blades, like machetes and axes, are done freehand with long flat stones to a convex edge. Not that I have that many mind you. Not a lot of wood to process in west texas.
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Nope. If anything, a convex is faster and easier to maintain than a flat edge of equal angle (in the context of field touch-ups) because it's going to be easier to hit just the apex. Think of a convex as being like a series of grinds that decrease in angle as they move back from the edge. Your stone will only be sharpening (rather than shaping) if it's hitting the apex, and even the slightest bit too shallow on a flat means you're contacting the shoulder rather than the apex. On a convex, that shoulder has already been ground off and your contact point is more likely to be pretty close to the edge where the abrasion may work down to the apex itself and then cause actual sharpening abrasion. Freehand sharpening in general is not going to be perfectly flat, so you're already making a convex.
What people believe is that, since they have a steady hand and are a good freehand sharpener, that they hold their knife at the exact same angle each stroke, then maintain that angle when they flip the knife over to do the other side.
They dont. No one does.
Now since that angle varies what they are actually doing is creating a series of microbevels of different angles. That is, convexing.
And that is why they are practical edges. They are impossible to not maintain. That is the "magic" of them. Not the "more steel behind the edge" silliness.
They dont. No one does.
Now since that angle varies what they are actually doing is creating a series of microbevels of different angles. That is, convexing.
And that is why they are practical edges. They are impossible to not maintain. That is the "magic" of them. Not the "more steel behind the edge" silliness.
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That skinny white(ish) stone in
FortyTwoBlades
signature is what I use on my machete. Technically a scythe stone, but it works great. The Arctic Fox.
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I wonder if maybe we are talking at cross purposes here?
‘Survival situations’ and, in fact, just serious use, demand a good edge. One doesn’t need a polished mirror edge to accomplish the tasks required. There is no need to whittle hairs, or slice phone book paper: the need does not arise.
A good, working edge can be achieved very easily, and easily maintained. It won’t win any Instagram contests on “whose blade is shiniest”, but that really is not the point, in a ‘Survival Situation’.
‘Survival situations’ and, in fact, just serious use, demand a good edge. One doesn’t need a polished mirror edge to accomplish the tasks required. There is no need to whittle hairs, or slice phone book paper: the need does not arise.
A good, working edge can be achieved very easily, and easily maintained. It won’t win any Instagram contests on “whose blade is shiniest”, but that really is not the point, in a ‘Survival Situation’.
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The diafold shouldn't have any problem dealing with a convex edge on the CRKT. I'd suggest watching a couple of YouTube videos for instruction on a good technique. Look for ones using handheld stones rather than bench stones. They'll translate to the diafold.