Freehand edge vs Guided system edge which will cut better?

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prime77

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Oct 11, 2006
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Take two identical knives with the same grinds and sharpened to the same degree at the edge. In the hands of a skilled sharpener will the freehand edge cut better than the guided system edge? It doesn't matter which system, edge pro/wicked edge/DMT aligner. Because of the slightly convex nature of a freehand edge with it's smoother transition at the shoulders of the bevel will it cut through material better than a guided edge with it's perfect bevel and angled shoulders or will they cut the same? Please excuse my rudimentary drawings but which will cut better (A) the guided system edge or (B) the freehand edge?

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I always found example B to provide a smoother cut and often with more control in a longer cut involving the whole blade. You can even the playing field by doing multiple bevels with a guided system though at that point I usually went back to hand sharpening. I liked the look of my grind better and the guide never brought me a edge that I couldn't produce myself.
 
Good to hear your input knifenut. It's interesting that you mention more control when using the full length of the blade. This is something I have noticed but forgot about. A freehand edge seems to sink into the material and maintain a straight cut. The only guided system I have ever used is a DMT magna guide. It's something I rarely use anymore.
 
Let's look at some scenarios:

1) vacuum: A same as B.
2) air/water: B (boat/bullet) is more aero/fluid dynamic, A has bigger shoulder vortex.
3) split wood: A wedge'em good.
4) cut soft wood: B penetrate more, less bounce.
5) other stuff for cutting: B cut more & lower friction, A need more force to tear and wedge (abrupt transition at bevel shoulder)
 
The convex side-effect of freehand sharpening performed by a skilled person is so small that you shouldn't be able to see the difference with the naked eye.
In theory though, a convex edge will offer less resistance due to the lack of shoulders, but as knifenut said, one can easily remedy the v-edge's shoulders by adding a relief bevel.
I wouldn't go so far as to say that freehand edges will give you superior edges to a guided system (because B is superior to A), simply because each sharpening system provides specific results.
There are many guided systems which will produce a convex edge, for instance; so, one could say that a guided system will produce a more uniform and "perfect" edge than a freehand one,
since there will always be some shaking and so on with freehand. Does it matter though in all practical terms? Not at all. Not even by a long shot, because some freehand sharpeners are extremely good at what they do.
 
My favorite edges are those that started out as fairly acute V-bevels, after which I convexed the shoulders of those bevels. The guided system is helpful to make the actual cutting edge as pure as it can be, relatively free of inconsistency brought by freehand sharpening. Just rounding & smoothing the shoulders, after the edge is finished, makes a noticeable improvement in cutting, every time I've done it.

I compared two knives, in cutting up a cardboard box recently. One was a pocketknife (Queen stockman w/D2 blades), and the other was an old 1965-vintage Case 6265 SAB Folding Hunter, with carbon steel. I'd used my Lansky system to re-bevel the clip blade on the stockman, to ~15 degree per side V-bevel. The Case had gotten the treatment I described above, by re-bevelling using a guided system (DMT aligner & Magna-Guide, with Dia-Folds), then convexing the shoulders on the V-bevel, using sandpaper on my strop block. What really struck me was, the Case's thicker blade (the secondary skinner blade, at ~1/8" thick), with the convexed shoulders on it's bevel, was a much, much slicker cutter in the cardboard, and even stayed armhair-shaving-sharp after I was done. The Queen's thinner blade (~1/16" or so), with the V-bevel and it's associated 'hard' shoulders, tended to grab & bind a bit in the cardboard. That was a real eye-opener for me. I would've expected the thinner blade to give more advantage, over anything else. But just convexing the thicker blade's shoulders seemed to make the vast majority of the difference. BTW, I've also noticed similar cardboard-cutting performance in an old '2-dot' Buck 112 in 440C (blade's at least as thick as the Case, maybe more so), which was convexed on sandpaper only. I didn't even use a guided system to form the new edge on that one; it's a fully-freehanded convex. It's also an amazing cardboard cutter, in spite of the thick blade.

So long as the cutting edge itself is fully apexed and pure, I'm absolutely certain the convexed shoulders improve upon an already good V-edge. I've yet to see an exception to that, in the 20+ knives I've done this way, so far. For this reason, I see no real inherent advantage in the 'perfect' flat bevels from a guided sharpener. Perfectly flat bevels still don't guarantee a fully apexed cutting edge. And being that the flat bevels come with hard, angular shoulders by default, I'm beginning to see some disadvantage there, as compared to a well-executed, fully-apexed and burr-free cutting edge with rounded, smooth shoulders.
 
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