How often do you thin?

[eazypeazy]

Sorry for the first post noob questions. Thinning seems daunting and confusing to me. I've got a typical Henckels (yeah, yeah, I'm working on it) beastly thick chef knife, and I'm wondering when it can be thinned. How often does one thin? Each time they sharpen? Do you thin the whole knife, or just add an increased secondary bevel so it's thinner behind the edge and leave the rest of the knife face alone? When does it "feel" like it's time to thin? Can you thin softer western steels or will their integrity be compromised? Sorry for all the questions. Thanks!

 

[icanhaschzbrgr]

It's a easy question really. When you feel the knife isn't cutting like it used to — time to thin. How often that happens? Depend on the knife and usage.
Obviously, when the knife was ground very thin behind the edge — it could go on without thinning longer compared to thicker knives.

When you sharpen knife — you are touching just the very edge (ideally). So over time, as you grind more and more metal away from the edge — it will became thicker. If it still performs nicely — no point to thin.

But if you aren't happy with performance, and you think it's because of the thickness behind the edge — then you need to thin it. It's a very personal thing actually. What is acceptable for me might not be acceptable for you and vice versa.

Western knives can be thinned as well, but you need to take into account their softness. If you make them as thin as Japanese makers do — they would cut well, but for a very short period of time. Soft steel won't keep edge for long, it will roll and bend. So over the life of western knife thinning would make a difference towards better cutting, but you shouldn't try to make it as thin as Japanese knives.

I don't thin my knives when I sharpen them, because they are very thin already. But many times I've thinned knives right after purchasing, because their stock geometry was too thick for my taste.

 

[K813zra]

It depends on the knife, for me. Something like my Ginga will get a light thinning behind the edge but on rare occasion as it is already so thing. Knives with wide bevels get thinned every time they see a full sharpening rather than a touch up. Typically I would say that for me thinning should happen any time the bevel is reset. I guess everyone is different, as was said above, though.

 

[krx927]

I think you can thin your Henckels a bit immediately. It comes way too thick.

I general I find that I need to thin the knife after every 3 to 4 sharpening to keep it in original shape. You can also nicely see the tickens by how big initial bevel is. Usually when you buy a (Japanese) knife the initial bevel is barely noticeable. After a few sharpenings it gets much bigger because the knife becomes thick behind the edge.

But like icanhaschzbrgr wrote, easiest way to spot something is not OK is through performance.

 

[Benuser]

I start every sharpening -- not a touching up -- far behind the bevel, at the lowest angle I'm comfortable with.

 

[Mucho Bocho]

I start every sharpening -- not a touching up -- far behind the bevel, at the lowest angle I'm comfortable with.

I'm with Ben (as usual)

 

[Nemo]

I start every sharpening -- not a touching up -- far behind the bevel, at the lowest angle I'm comfortable with.

On the same stone that you begin sharpening the edge with or a more coarse stone?

E.g.: if you are sharpening with a 1000, do you thin with a 1000 or say a 400?

 

[Benuser]

Same stone, Naniwa Pro 400 or 800.

 

[Dave Martell]

Always start by hitting the top (shoulder) of the bevel and working your way down to the edge/burr. If you do this each time you do stone work you're thinning as you go. It won't add up to much performance gains but it'll keep your edge thin longer than sharpening it any other way.

Now there's another thinning where you purposely work at much lower angles to actually thin "behind the edge" (which is actually above the edge) to make for performance gains. This can be a little or a whole lot of work - your choice. Some folks do this every time they sharpen.

 

[Badgertooth]

I start every sharpening -- not a touching up -- far behind the bevel, at the lowest angle I'm comfortable with.

+ 1

 

[Nemo]

Always start by hitting the top (shoulder) of the bevel and working your way down to the edge/burr. If you do this each time you do stone work you're thinning as you go. It won't add up to much performance gains but it'll keep your edge thin longer than sharpening it any other way.

Now there's another thinning where you purposely work at much lower angles to actually thin "behind the edge" (which is actually above the edge) to make for performance gains. This can be a little or a whole lot of work - your choice. Some folks do this every time they sharpen.

If you do option 2, does it turn the blade into a wide(ish) bevel? Do you then follow that widish bevel as a thinning bevel for subsequent sharpenings?

 

[brianh]

I've never thinned, only touched up and sharpened. Anyone care to share any pics? I would think a kurouchi finished blade would be easier to thin visually than say a monosteel carbon. I've seen Jon's videos but good pics would be very useful.

 

[Badgertooth]

I start every sharpening -- not a touching up -- far behind the bevel, at the lowest angle I'm comfortable with.

Also, it's essential for natural stones to start the process of slurry generation

 

[foody518]

If you do option 2, does it turn the blade into a wide(ish) bevel? Do you then follow that widish bevel as a thinning bevel for subsequent sharpenings?

How it looks will depend on the thickness and geometry of the knife in question as well as how tentative or aggressive your angle(s)

That is my "thinning bevel" and the primary bevel is tiny

 

[Anton]

Also, it's essential for natural stones to start the process of slurry generation

May help others, You mean prior to thinning or as a result of the "every" sharpening step

 

[labor of love]

How it looks will depend on the thickness and geometry of the knife in question as well as how tentative or aggressive your angle(s)

That is my "thinning bevel" and the primary bevel is tiny

I was going to post a pic of a gyuto that I do basically the same thing for.

 

[v647c]

If you feel the knife cuts well then there isn't any need to thin it. As others have mentioned, simply removing the "shoulders" of your edge should give you a noticeable performance increase. Creating a thinning bevel that's too defined will result in there being shoulders that could be felt while cutting. I think the best way is to simply blend the edge into the knife by sharpening at the lowest angle after sharpening the actual edge. I feel it's less complicated to do than creating a thinning bevel, and the knife will definitely have an easier time sinking into product.

Wide bevel or convex grind, doesn't matter

 

[qjlforever]

too thin is not good. its lightness,you can not handle it well and do fast job.

 

[Badgertooth]

May help others, You mean prior to thinning or as a result of the "every" sharpening step

As a result of the "every" sharpening step. Just wrangling with my first cleaver now.. that it had me beat but I got the hang of it now behind the bevel.

 

[malexthekid]

My only problem with the thin at every session is the refinishing required. On a wide bevel it makes sense. But on others not so much for me...

 

[WOK-a-holic]

Thin once when new .
maybe again many year's later if needed .
usually one time .

 

[XooMG]

I just got used to uglying up my knives so I could regularly thin. I generally favor knives that provide a dedicated thinning and maintenance space. On a recent refinish, I decided to leave a usable stone path, though it might look less appealing than a full polish.

 

[Sleep]

Recently thinned my Itinomonn because it was starting to cut poorly. It'd be the 2nd or 3rd thinning in the year or so I've owned it. And that's my main work knife.

 

[krx927]

My only problem with the thin at every session is the refinishing required. On a wide bevel it makes sense. But on others not so much for me...

1+

thinning a bit every time you sharpen and not refinishing the knife means you have ugly knives all the time...

 

[Benuser]

With carbons the patina very quickly reappears

 

[labor of love]

If you thin a blade regularly along with sharpening sessions then we're talking about a simple 320-400
Grit stone. Something you can clean up with a mid grit stone potentially, which is the next step in the sharpening progression anyway. Then clean up behind the edge with micro pads or just let it all hang out until next time.

 

[Mucho Bocho]

Ok in this circumstance, I'm defining thinning, as the first step in sharpening a knife. I lower the blade as close as I can without touching the blade face against the stone (3 to 5 degrees or lower), it will leave scratches about 2mm from the edge, but those will be polished out on higher grit stones. No blade face refinishing required.

THINNING can also be performed by laying the knife on the stones and grinding away each side 5 to 10mm up the blade face.

To clarify, when I sharpen I thin every time as part of proper maintenance. Sometimes a knife would benefit from a or multiple THINNING, which as mentioned, requires the blade faces to be refinished. (Carter Muteki).

1+

thinning a bit every time you sharpen and not refinishing the knife means you have ugly knives all the time...

 

[krx927]

With carbons the patina very quickly reappears

If you thin a blade regularly along with sharpening sessions then we're talking about a simple 320-400
Grit stone. Something you can clean up with a mid grit stone potentially, which is the next step in the sharpening progression anyway. Then clean up behind the edge with micro pads or just let it all hang out until next time.

You are both true but still it does not look same if you properly refinish the knife. But in the future I will start doing it like this regularly = thinning a bit when I sharpen. I really hate when I need to do big thinning.

I tried this 2 weeks ago with my Watanabe 240. It was OK and at the end I forced the patina so it does not look that bad, but still way off what it looked before.

 

[foody518]

With carbons the patina very quickly reappears

On my carbon monosteel knife shown in post #14, the thinned area will patina and not be very perceptibly different than the blade face above it. Of course, factors like vertical vs horizontal grind lines+ your sharpening technique will affect how blended or not this looks

 

[Ruso]

If you do option 2, does it turn the blade into a wide(ish) bevel? Do you then follow that widish bevel as a thinning bevel for subsequent sharpenings?

Yep, you are correct in general terms.