Polished Edge: When, Why, What Steels??

[Bloke]

I don’t worry about polishing the edges on work knives.

Going out knives are a different kettle of fish. Such knives I polish all edges to a brilliant mirror. That way when I’m at a dinner party, let’s say, and people are looking at me funny, I can discreetly pull my knife from my pocket and check if there’s parsley or something stuck in my teeth or on my chin. :eek:

Basically, polished edges same me having to carry a compact. :cool:

[jpm2]

Now if anyone cares to go past things that we can all test in the real world and think about theory: Wouldn't one of the main reasons to work up a grit progression to a polished edge be to reduce subsurface damage to as shallow of an area as possible? This would explain anyone's feelings that polished edges seemed more durable, as well as having a more consistent texture and therefore less crack initiation points. Hence polishing and then following with a coarse microbevel.

I do this quite a bit, when there's time (it really only takes a few extra minutes), going a few grits higher than I want with very light pressure to really clean up the edge, then a few very light strokes backwards to the coarser grit I want.
I end up with noticeably more durable edges this way than just stopping at the grit I'm aiming for.

[Sharp Guy]

Some of you guys get way too deep into this stuff for me :D I try to keep it simple, I sharpen my knives until I feel it's as sharp as I want it. Then I cut the things I need to cut and continue doing so until the knife doesn't cut how I like anymore. Then I repeat. I like science and all but it I really don't want to get a headache overthinking how to sharpen a knife lol

I think it's BFK that has Sal's quote in his tag line. Something about edge Junkies just being nuts! Spot on haha :)

Haha, some folks are happy having a car that gets them from A to B, some want to mod and tear things apart and eek out every last bit of HP they can. Different strokes :D

I'm more interested in the details than I let on. I just had to laugh when the one guy felt the need to announce he's a R&D engineer :rolleyes: and the other guy asking him to clarify his stance a data point. My girl took my proton microscope and my pocket protector away. So I don't feel like I can play anymore

[ChrisinHove]

I don’t worry about polishing the edges on work knives.

Going out knives are a different kettle of fish. Such knives I polish all edges to a brilliant mirror. That way when I’m at a dinner party, let’s say, and people are looking at me funny, I can discreetly pull my knife from my pocket and check if there’s parsley or something stuck in my teeth or on my chin. :eek:

Basically, polished edges same me having to carry a compact. :cool:

:D

[Manifestgtr]

XHP, K390 and Cruwear…all polished, all the time.

I know there are people who are very vocal about their preference for coarse finishes but I often like a polished edge. I do a lot of fiddly, random wood working for my job and not only does it make for better precision, it also leaves the work nicely finished. On top of that, I LEGITIMATELY believe that certain steels perform as well or better with a polished edge. K390 holds a very stable edge, it holds its sharpness for a long time and doesn’t crumble with use. I’ve finished my K390 dragonfly down to .1 micron, used it normally for several weeks and the stupid thing was still whittling hair.

I understand the physics of coarser edges. I understand why some guys prefer them…and I do keep coarse edges on a few of my knives. They’re fine but unless I’m breaking down masses of cardboard, I like a polished edge.

[Bloke]

I do a lot of fiddly, random wood working for my job and not only does it make for better precision, it also leaves the work nicely finished.

I like to whittle from time to time and only use zero ground Scandi’s all fairly polished. I love the “polished” finish they leave on the timber I cut and I gauge sharpness by that finish more than anything else. :)

[Evil D]

I tend to go through the whole grit progression and even strop my serrations so I guess at least my micro bevel is fairly polished. There's just something really special about serrations that can push cut things. For plain edge I like 600-1000 most of the time, I do touch up on the Sharpmaker so the micro bevel on those probably gets a little polished too. My days of actually polishing the whole bevel are over though, to me that's mostly just for looks. I've done a couple of my nicer gent's knives for that reason but my users don't need it.

[hambone56rx]

My work knives I prefer a mirror polish bevel set followed by a sharpmaker medium microbevel.

Now if anyone cares to go past things that we can all test in the real world and think about theory: Wouldn't one of the main reasons to work up a grit progression to a polished edge be to reduce subsurface damage to as shallow of an area as possible? This would explain anyone's feelings that polished edges seemed more durable, as well as having a more consistent texture and therefore less crack initiation points. Hence polishing and then following with a coarse microbevel.

Vaugith,

This makes sense! I haven't done any microbevels, so could you explain how you do yours? The 20 degree side of the sharpmaker? And on the medium stones? On the edges or the flats? Just a couple strokes?

THANKS!

Hamilton

[Vaugith]

This makes sense! I haven't done any microbevels, so could you explain how you do yours?

Yeah, I usually sharpen somewhere around 15 to 17 degrees per side, deburr and repair damage on the stones. Edge is very sharp at this point, capable of push cutting newsprint against the grain whisper quiet. No stropping on compressable materials such as leather at this step especially with compounds as that introduces microconvexity which can mean your microbevel won't hit the apex. The microbevel will get rid of any bits of burr hanging on anyway.

Sharpmaker medium rods at 20 degrees per side, on the flat part of the rods, edge leading, alternating sides every stroke, feather light pressure, just a few passes. If you can see the microbevel with the naked eye you've gone too far. I find the microbevel helps to prevent chips and rolls as well as giving me the more coarse edge texture I prefer as well as making touch ups really a breeze. I understand many folks sentiment that they don't have time for high polish edges every time. But I just need to do that step once in a great while. I can touch up on the sharpmaker in seconds quite a few times back to shaving sharp before I need to reset the bevel.

You could apply a microbevel with any sharpening stone by following the same method and just freehanding a slightly increased angle vs the bevel. The sharpmaker is just an extremely convenient package and the brown rods happen to be my favorite abrasive I've tried for this application.

[wrdwrght]

Some of you guys get way too deep into this stuff for me :D I try to keep it simple, I sharpen my knives until I feel it's as sharp as I want it. Then I cut the things I need to cut and continue doing so until the knife doesn't cut how I like anymore. Then I repeat. I like science and all but it I really don't want to get a headache overthinking how to sharpen a knife lol

I think it's BFK that has Sal's quote in his tag line. Something about edge Junkies just being nuts! Spot on haha :)

Haha, some folks are happy having a car that gets them from A to B, some want to mod and tear things apart and eek out every last bit of HP they can. Different strokes :D

I'm more interested in the details than I let on. I just had to laugh when the one guy felt the need to announce he's a R&D engineer :rolleyes: and the other guy asking him to clarify his stance a data point. My girl took my proton microscope and my pocket protector away. So I don't feel like I can play anymore

Until most here are experimental physicists, with all the equipment needed for accurate characterization of steel and other knife properties, I think we should not expect more than the experience-based anecdotes that this forum usually offers. We just need to remember that some grains of salt may be needed to season them.

[jpm2]

....parsley or something stuck in my teeth or on my chin. :eek:

Basically, polished edges same me having to carry a compact.

:D

Some people can't look into glass mirrors...

[vivi]

How about axes?

Most folks I know leave theirs very coarse. I like to run a polished edge on mine.

Makes more sense to me since axes push cut, and like we've been discussing here I think more polished bevels have better stability at the apex.

Machetes I like to leave coarse though. Makes sharpening them much faster, the soft steel doesn't hold a polished edge very well, and I like how the coarse edge grabs plant growth as I slash through it.

[vivi]

I'm an R&D engineer by trade, and I've pointed out issues with your methodology in the past and you haven't seemed particularly interested in that feedback.

You're correct, I'm not particularly interested in someone claiming I am wrong, without explaining why.

So if you think polished edges have superior edge retention, maybe post why? Or make a video?

My videos are not controlled scientific studies, we do agree there. They're just casual videos meant to show general observations, e.g. this coarse edge will cut this rope more times than this polished edge, or this X grit stone will give Y knife a shaving sharp edge, no grit progression required.

[Woodpuppy]

I think the only 2 I’ve gone for polished edges with are the AEB-L Urban and the Cruwear Millie. It’s too much work so I don’t do it routinely. I sharpen until I can shave cleanly and call it good.

[Manifestgtr]

I like to whittle from time to time and only use zero ground Scandi’s all fairly polished. I love the “polished” finish they leave on the timber I cut and I gauge sharpness by that finish more than anything else. :)

Yeahhh, I keep my Mora sloyds all polished for that exact reason. That and…you know…an enormous, highly polished scandi grind looks incredible. No use in denying that fact.

[hambone56rx]

This makes sense! I haven't done any microbevels, so could you explain how you do yours?

Yeah, I usually sharpen somewhere around 15 to 17 degrees per side, deburr and repair damage on the stones. Edge is very sharp at this point, capable of push cutting newsprint against the grain whisper quiet. No stropping on compressable materials such as leather at this step especially with compounds as that introduces microconvexity which can mean your microbevel won't hit the apex. The microbevel will get rid of any bits of burr hanging on anyway.

Sharpmaker medium rods at 20 degrees per side, on the flat part of the rods, edge leading, alternating sides every stroke, feather light pressure, just a few passes. If you can see the microbevel with the naked eye you've gone too far. I find the microbevel helps to prevent chips and rolls as well as giving me the more coarse edge texture I prefer as well as making touch ups really a breeze. I understand many folks sentiment that they don't have time for high polish edges every time. But I just need to do that step once in a great while. I can touch up on the sharpmaker in seconds quite a few times back to shaving sharp before I need to reset the bevel.

You could apply a microbevel with any sharpening stone by following the same method and just freehanding a slightly increased angle vs the bevel. The sharpmaker is just an extremely convenient package and the brown rods happen to be my favorite abrasive I've tried for this application.

THANKS!!

Hamilton

[Woodpuppy]

Something appears amiss with the new emojis- they’re ENORMOUS!

[u.w.]

they are, and

it's makin' me laugh...

u.w.

[Fireman]

Mrrrrca!!!!!



The one side polished and one side toothy may suit most people’s needs.

[Bill1170]

I only polish my ZDP knives because that stuff works brilliantly with a high polish convex edge.