Razor vs toothy edge

I sharpen to 15K Shapton, then strop on CBN/nanocloth to whichever grit I intend to finish at. Usually, .5 micron, but some of my "bragging rights" knives are finished at .25 or .125 CBN.

Much of my sharpening is as much a "Zen" experience as it is a knife sharpening experience
 
Much of my sharpening is as much a "Zen" experience as it is a knife sharpening experience

What is the sound of one blade stropping?

(A former student of Zen back in the day. Used to attend a Zendo in NYC...but most of my study was on my own.)
 
So I don't have a set-up I can do this on at the moment, so I'm wondering if anyone else has tried this: It's a variation on micro-beveling. Instead of changing the angle on the edge, I want to leave the edge alone, and semi-coarse for some bite, but then drop the angle a touch and polish the area behind the edge and maybe round the shoulder a bit.

Seems like you'd get some of the advantages of both finishes. Or it could just be a lot of extra work for nothing. I'm guessing it might take a strop to actually accomplish this. I'd love to hear from someone who's done this.
 
So I don't have a set-up I can do this on at the moment, so I'm wondering if anyone else has tried this: It's a variation on micro-beveling. Instead of changing the angle on the edge, I want to leave the edge alone, and semi-coarse for some bite, but then drop the angle a touch and polish the area behind the edge and maybe round the shoulder a bit.

Seems like you'd get some of the advantages of both finishes. Or it could just be a lot of extra work for nothing. I'm guessing it might take a strop to actually accomplish this. I'd love to hear from someone who's done this.

That's real easy to do with a strop. Especially for rounding the shoulder (convexing) behind the edge; something like a hard-backed denim or linen strop with a fast-working, aggressive-polishing compound appropriate to the steel works very well. A hard-backed fabric strop has just enough 'give' to convex the steel behind the edge very effectively. For simpler steels up to something like 154CM or even D2, something like white rouge or other aluminum oxide polishing compounds work fast (like Flitz, Simichrome, Mother's Mag, etc). For high-wear steels with a lot of vanadium, diamond or cbn compounds would be better.

It may be wise to do the polishing/convexing behind the apex first, and then use whichever coarser-grit hone you prefer, to finish the edge. With aggessive-polishing compounds on a denim strop, it's pretty easy to take some of the apex's 'bite' away, pretty fast, if the angle raises a bit on the strop. So doing the polishing behind the edge first is probably a better approach, then raise the spine a little and finish the edge as you want it, on a stone.
 
Hey guys, I have a question about different degrees of sharpness and what they're good for.
Why do different (toothy to razor) edges cut different things better? For example, why does a toothy edge cut meat better than a razor edge.
And what uses does each degree of sharpness have, Ie. Toothy, semi sharp, sharp, shiny, razor.

Thanks for the help, guys,

Bo

My answer won't be as in depth...

There are members here who will be able to guide you on how to achieve different edge types much more in depth than I can, and that is valuable info...

From my uses I've found toothy edges and polished edges both cut meat very well. For wood, a polished edge seems to cut longer. For cardboard push cuts a polished edge cuts well. For saw cuts a toothy edge cuts better than a polished edge. I'm not sure there is a definitive answer until you figure it out from your own use.

Good luck on your adventure!
 
^^^^One of the benefits of multi-blade traditional knives is that you can have blades set up for coarser or finer work on the same knife.

I'm happy with a well sharpened blade anywhere between a bit toothy and somewhat polished. Most of my knife needs are not so specific that my day will be ruined if it's not one or the other.

(Of course, if I'm whittling or push cutting, a polished edge is preferred.)
 
What would the advantages be of rounding the shoulder?

Molokai: okay, that helps. Thank you.

Blues: yes, my uncle gave me his trapper to sharpen and gave him a razor edge on 2 of his blades and a more toothy edge on his other blade. Although the method I used didn't give it THAT toothy of an edge.

Thanks guys,

Bo
 
What would the advantages be of rounding the shoulder?

(...)
Bo

Rounding & polishing the shoulder can reduce drag / friction in deeper or tougher materials, like heavy cardboard. A very crisp & hard-edged shoulder on a V-bevel can get hung up in heavy cardboard; rounding the edge of the bevel's shoulder and then polishing it can make the same cutting job suddenly scary-slick & easy. My favorite cardboard-cutting edges are always convexed at the shoulders & polished, behind the edge; this makes a more dramatic difference on blades that are relatively thick, especially.

I've also liked doing this with kitchen knives used for fruit/veggie slicing & chopping, for the same reasons.

THIN grind + acute edge angle + convexed shoulders with polish = laserbeam, effortless slicing. :)
 
Spyderco medium stone gives a medium edge that can whittle hair and still be toothy.My favourite edge is off dmt coarse stone,very agressive and sharp,best for meat cutting.
 
Okay, so if I strop at a Lower angle will I achieve this rounded shoulder?

Thanks,

Bo

With a compound that removes metal pretty aggressively, yes. You might try it out with an inexpensive kitchen knife or another in a similar steel (420HC, 440A, etc), using a compound like one of those I mentioned earlier, to see how it'll work. Denim and linen strops used with compounds like those will work very fast to that effect.
 
For me it all depends on the knife knife’s for whittling I want them to have a very fine edge knives for every day use I really don’t care as long as it’s sharp.
 
What would the advantages be of rounding the shoulder?

The long and the short of it is it makes it thinner. And thinner cuts better with less resistance. The closer you get to the edge, the greater the magnitude of influence the geometry has on cutting performance, and since the edge shoulder is right behind the edge, it may not play as big of a role as the edge apex thinness or the edge angle behind that apex, but it's the next most influencing geometry trait. It reduces how much deflection or wedging force occurs during the cut, allowing more of the applied force to go into the actual act of cutting rather than displacing the cut material to make way for the blade.
 
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