Mirror polish vs toothy edge?

[Backyard]

I find a toothy edge for most tasks cuts better bit doesn't last as long as a polished edge. It is also far easier to touch up a toothy edge but needs to be done more often. I do a polished edge when I sharpen others knives as I feel the slightly longer life and prettiness of the edge is a better selling point, not that I get paid for it anyways.

 

[rick melear]

Give me a Dozier in D2 with a toothy edge any time

 

[MtnHawk1]

For your kind of needs I’d stop at 220 grit, then strop on leather that has Green Chrome polishing compound to remove any burr for a good 20 strokes each side.

Doesn't the stropping remove or diminish the toothy edge?

Requiescat in pace, 600 grit is a little high for a toothy edge, IMO, although of course whatever works best for you is best for you. I finish at 120-325 grit but tend towards the lower side of that. I think 220 grit is a good one to start with, then if you want you can experiment with going either higher or lower.

As Rhinoknives1 said, Stay Safe!

 

[jpm2]

Maybe it's a different topic and I gladly delete it but has anyone noticed a difference with steels used? I recently started using K390 and somehow I can't get them above just shaving sharp.
It might be tempering but maybe it's just that k390 just wants a 'toothy' edge.

What are you sharpening with?

 

[Sonnydaze]

I agree that a toothy edge cuts better; a mirror edge looks pretty. Sometimes, I will sharped to 6,000grit and...THEN...change the angle on the Edge Pro for a 3 degree/edge more obtuse edge. This roughens the edge, but leaves the mirror undisturbed..

 

[Twindog]

The question is not framed well. A mirrored edge is beautiful, and to my sensibilities, makes a collection knife shine.

But a mirrored edge is way too difficult to maintain if you're actually using your knife. The question is whether you want a ragged edge or a refined edge -- not mirrored. There are uses for both.

Personally, I prefer a refined edge. It cuts much better in most circumstances -- tomatoes and cattle testicles aside.

For general purposes, 1,000 grit -- properly stropped -- is excellent for EDC. Higher grits will cut even better.

All this depends on your ability to completely remove the burr and leave a clean, stropped edge.

 

[miso2]

To me, a coarse edge is beautiful, too.

I sharpen my knives with high carbide steels (like S35VN) at #150 and lightly refine the edge with DMT EEF (#8,000) at a slightly higher sharpening angle (15 to 17~18 DPS).
The "bite" seems to last quite long for these steels.

I find that it is not true for low carbide steels like 1095 and 420HC.
The "thumb skin stickiness" goes away quick.
I tend to put polished edges on these blades lately.

 

[000Robert]

I like a toothy edge of anywhere from 600 - 1000 grit. But if you want a nice polished edge but still want a decent toothy edge that will cut when you need it to, then put a micro-bevel on it like Sonnydaze mentioned. Say for instance that you put a polished edge on your blade at 20dps that is mirrored and gorgeous. You can put a toothy micro-bevel on it at 24dps. You'll still have your mirrored edge, but also a toothy edge apex if you happen to need to cut stuff.
I rarely mirror polish an edge, but when I do I always put a toothy micro-bevel on it.

 

[afishhunter]

Depends on the blade steel.
I read in one of @Larrin 's articles that some steels, such as S30V, perform better, and hold an edge longer with a "toothy" edge, than a highly polished one. Other steels (I think he said D2 is one) do better with a highly polished edge.

My "finest" stone/hone/plate is a "600 grit" diamond plate. To date, I haven't "needed" anything finer.

Disclosure: I have no idea what "grit" my old "Soft", "Medium", and "Hard" Arkansas stones I had between circa 1961 and 2015 were. The "Medium" and "Hard" might have been finer than "600 grit", but I don't know if they were.

 

[Horsewright]

Thank you for your reply, I had no idea that answers were almost instant on this forum. Could you advise me on the optimum grit for a toothy edge?
Kind Regards

For your kind of needs I’d stop at 220 grit, then strop on leather that has Green Chrome polishing compound to remove any burr for a good 20 strokes each side. I’ve used this level of toothy edge for leather , Rubber, Canvas & other materials . Plastics, small wire and pretty much all of the things you would encounter in your line of work. Stay safe! BTW, your Mirror edge is for food prep, Sushi type work. Shaving hair in a push cut.

My procedure is very similar to Laurence's. After grinding the secondary bevel with a 120 grit belt I move to a 220 silicone carbide belt. After the 220 belt I move to the buffer with green scratch remover compound to remove the burr and polish the very apex of the edge. Just a couple light passes each side, thats it. Sharpening is the last step on each batch of knives that I do besides a final wipe down by hand. I expect each knife to slice paper cleanly without drag, three times. If one fails I go back to the 220 belt again and then the buffer again too.

Outside at the grinder:

Testing:

Sharpened and ready for the wipe down:

Some folks had mentioned that the type of edge depends on what you cut and there is some truth to that. I do make leather crafting knives too. The edges on these are taken to 800 girt and then polished:

Each roundknife makes its own sheath before its shipped to make sure the edge is right:

I expect them to cut heavy saddle leather such as on this rifle scabbard in a single pass:

But outside of leather work I really like a toothy edge. For kitchen work I kinda split the difference. Kitchen knives I take to 400 grit and then hit the buffer:

Sharp enough to make the onions cry.

 

[Catdaddy2]

"Sharp enough to make onions cry" That's pretty good. Made me smile

 

[Dr Heelhook]

If you are cutting wood and you want the wood to look nice, you should have a polished edge.

 

[Horsewright]

"Sharp enough to make onions cry" That's pretty good. Made me smile

Its a customer's qoute. I stole it.

 

[BD_01]

For most tasks, a fine but still toothy edge always seems to cut best for me.

I’m far from a sharpening expert, but when I’m reprofiling with my KME I just can’t stop until I’m at a 17-18° near-mirror polish (3 micron film and strop with 1 micron paste).

When I feel the edge needs a touch-up or more bite, I’ll touch it up with the 20° Sharpmaker. It’s the best of both worlds, as some people have suggested.

Honestly, the very best and longest lasting edges I’ve ever done were near polish 17.5° convex (WSKO) followed by a good 20° Sharpmaker micro. I gave up on that because unless you’re really focused, it’s easy to get the bevels asymmetric on a WorkSharp. (I decided to spring for a KME vs getting the Blade Grinding Attachment).

 

[000Robert]

For most tasks, a fine but still toothy edge always seems to cut best for me.

I’m far from a sharpening expert, but when I’m reprofiling with my KME I just can’t stop until I’m at a 17-18° near-mirror polish (3 micron film and strop with 1 micron paste).

When I feel the edge needs a touch-up or more bite, I’ll touch it up with the 20° Sharpmaker. It’s the best of both worlds, as some people have suggested.

Honestly, the very best and longest lasting edges I’ve ever done were near polish 17.5° convex (WSKO) followed by a good 20° Sharpmaker micro. I gave up on that because unless you’re really focused, it’s easy to get the bevels asymmetric on a WorkSharp. (I decided to spring for a KME vs getting the Blade Grinding Attachment).

The BGA is much better with the WSKO for sharpening knives. It's about the only way I use it.

 

[BD_01]

The BGA is much better with the WSKO for sharpening knives. It's about the only way I use it.

I still might pick one up someday.

 

[olivier coen]

What are you sharpening with?

I usually use the belt grinder 120, 200, 400 grid and move to trizact 30, 16 and 6 after if I want 'bushcraft polished' after that I use 0,5 micron dmt on MDF wheel.
It works perfectly on most knives (although I might be able to skip a few passes) but it didn't seem to work on the last k390 knife.

Was wondering if I somehow screwed up HT.
I tried hand sharpening on DMT 'stones' and the real world sharpness is great, just wanted that little bit extra.
To be clear, I get it rough shaving sharp but not beyond that.
So maybe k390 is not for making razors

 

[000Robert]

I usually use the belt grinder 120, 200, 400 grid and move to trizact 30, 16 and 6 after if I want 'bushcraft polished' after that I use 0,5 micron dmt on MDF wheel.
It works perfectly on most knives (although I might be able to skip a few passes) but it didn't seem to work on the last k390 knife.

Was wondering if I somehow screwed up HT.
I tried hand sharpening on DMT 'stones' and the real world sharpness is great, just wanted that little bit extra.
To be clear, I get it rough shaving sharp but not beyond that.
So maybe k390 is not for making razors

Do you use a wet grinder?

 

[Heirphoto]

For light EDC tasks I usually go 1000 grit then strop. Harder use work knives (yard, garden, woods) go 600 grit and strop to remove the burr
My wood working tools however, plane irons and chisels go to 12K then strop as they are basically push cutting rather than slicing

 

[olivier coen]

Do you use a wet grinder?

For K390 i don't, it's been tempered at 550c 1022 f and I slow my belt down significantly. occasional dips in water and light passes should do the rest.