# What am I doing wrong?



## TheOneHawk (Sep 1, 2014)

So I've gotten pretty proficient at sharpening my current knife, a Mercer, and have the sharpest knife in the kitchen as far as I'm aware. People have noticed this, and one of my coworkers asked me to sharpen his knives today, a MAC and a Henckel. I've done nothing different as far as I can tell between the three knives, except spend significantly more time on his in order to establish a new bevel, yet mine is infinitely sharper than either of his. I would feel bad returning him his knives like this, sharp but not as sharp as my own, yet no matter what I do I can't seem to get them up to the standard of my own knife. My knife has never seen anything but waterstones, while his regularly see knife grinding tools, would that have anything to do with it?


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## jared08 (Sep 1, 2014)

I would guess they need to be thinned behind the edge. This will allow you to put a lower angle cutting edge on them and improve how they cut.


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## TheOneHawk (Sep 1, 2014)

it's not how they cut, it's the edge itself. I can't actually test how they cut since I have no available food where I sharpen. I dropped back to my mid grit stone and back up to the 5K and it's definitely sharper now. I must just not have given it enough time on the 1200? Idk.


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## jared08 (Sep 1, 2014)

If they used power tools on it you may need to start on a low grit stone and completely grind new bevels. Draw a burr then work through your progression.


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## TheOneHawk (Sep 1, 2014)

I did exactly that. Started on a 500 and the bevels are completely new. It's definitely sharp, but the edge feels wrong and it shaves arm hair poorly.


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## icanhaschzbrgr (Sep 1, 2014)

How did you approached deburring?


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## psfred (Sep 1, 2014)

If those are fairly soft stainless (likely the Henkles is), they can be a problem to sharpen. Use very light pressure and remove the burr as soon as it forms by making very light strokes on alternate sides of the blade until you cannot feel it any more BEFORE you move to the next stone. Otherwise, the burr will simply wipe back and forth on the finer stone and never go away. Not a bad idea to use a felt block or a piece of soft wood to de-burr as well for each stage.

Draw a minimal burr after your coarse stone, at 1000 grit you are really finishing the edge on soft steel, not grinding it so much. Finish with a 3000 grit stone or strop, and maybe polish a bit on a chromium oxide charged strop, a finer edge won't last long enough for it to make a difference, and you will need some "tooth" to get those knives to cut will.

A couple passes with a steel can make a big difference too -- very light, you just want to stand the edge up straight. No abrasive honing rods, no serrations, just a hard steel rod wiped down the blade works best.

Peter


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## Mrmnms (Sep 1, 2014)

Assuming you raised a decent burr with 500 and 1000, you may be doing more harm than good going to the 5 k stone. I finish Henkels at 1 to 2 k.


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## kevpenbanc (Sep 1, 2014)

I have some sabatiers, mundials and a wusthof and I can get them nowhere near as sharp as any of my *** knives.
Nice edges, but not in the same league. 
Maybe some of them need some thinning, don't have the experience to know. Two of them are fairly thin blades, but sam mediocre (relatively) edges.


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## kevpenbanc (Sep 1, 2014)

*** => japanese knives

Not sure what happened there !!


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## Benuser (Sep 1, 2014)

Carbon or stainless Sab's?


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## kevpenbanc (Sep 1, 2014)

Benuser said:


> Carbon or stainless Sab's?



Sorry, should have specified.
Stainless Lion Sabs.


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## Benuser (Sep 1, 2014)

kevpenbanc said:


> Sorry, should have specified.
> Stainless Lion Sabs.


I asked because both soft steel types require an opposite strategy. The Lion stainless ask for a very coarse edge. Think silicon carbide stones with a lot of pressure, deburring on a JIS400 waterstone perhaps, or a finely grooved steel. The Wüsthof can deal with a slightly finer treatment, think JIS800, and deburring on a slightly finer medium. I use a dry 2k for that. 
Don't think about polishing these edges. They won't hold.
As for soft carbons, they benefit from high polishing and get crazy sharp because of their very fine grain.


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## WingKKF (Sep 1, 2014)

If the OP's coworker's knife has regularly seen grinding tools, could the steel have been damaged by overheating?


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## Benuser (Sep 1, 2014)

WingKKF said:


> If the OP's coworker's knife has regularly seen grinding tools, could the steel have been damaged by overheating?


+1
Or fatigued by a lot steeling?
In both cases make sure to remove a bit of steel to get a fresh edge.


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## kevpenbanc (Sep 1, 2014)

Benuser said:


> I asked because both soft steel types require an opposite strategy. The Lion stainless ask for a very coarse edge. Think silicon carbide stones with a lot of pressure, deburring on a JIS400 waterstone perhaps, or a finely grooved steel. The Wüsthof can deal with a slightly finer treatment, think JIS800, and deburring on a slightly finer medium. I use a dry 2k for that.
> Don't think about polishing these edges. They won't hold.
> As for soft carbons, they benefit from high polishing and get crazy sharp because of their very fine grain.



Thanks for the info.


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## psfred (Sep 1, 2014)

Excessive use of horrible things like pull through sharpeners with carbide or very hard steel disks, serrated knife steels, or belt sanders can leave the edge of the knife in terrible shape. Shouldn't be as much of a problem with soft stainless as with high hardness carbon steels, but getting rid of the damage done by such things can require removing some metal from the edge.

You should get a magnifier -- 20x is about all you can manage by hand, but having a moderate quality loupe of that magnification will allow you to take a look and the actual edge magnified enough to see what's going on there. Very likely you will find either a folded burr or edge damage deep enough that only a fraction of the edge is actually sharp. 

Pull throughs are particularly bad, as they flex the edge as it goes past the pair or double pair of washers. This can fracture the steel (in fact, is certain to fracture Japanese steel edges) and you will have to grind away the badly damaged steel to get rid of the microcracks and missing bits. The edge can end up very wavy from uneven material removal.

Ditto for serrated knife steels, especially is someone is using them with great pressure to actually remove metal. The localized pressure is high enough as the steel is forced down the blade to cause it to acquire a wavy profile, and when you sharpen it it can become very slightly serrated with unequal metal removal. The "valleys" can have a bit of burr stick since you aren't actually grinding to the apex. Hard to see by eye. I cringe when I hear someone describe using a steel with enough pressure to actually remove metal -- a steel should only be used to re-align a folded edge. If the edge won't come back up, it's time to sharpen, not abuse the knife with a very high pressure point moving down one side at a time. 

Try re-sharpening the blades you aren't getting sharp, and see if you can find a magnifier of some sort. Even a cheap magnifing glass will help.

Peter


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## MAS4T0 (Sep 2, 2014)

What kind of sharpness tests have you done?

Is it possible you're expecting them to get sharper than is feasible for them?

Depending on the skill level of the operator, it's possible that the edge is slightly wavy from sharpening on the grinder and as such the blade isn't sharpening or deburring properly. I had that problem with my parents knives until I reset the bevel.


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## TheOneHawk (Sep 2, 2014)

Yeah, some of the stuff people do to their knives here are just... ugh. I've got a couple people coming to me for knife sharpening now, and while they are paying me for it, I'd do it for free just so I don't' have to listen to them grind their knives on pullthrough sharpeners anymore. 

I managed to get them sharper, though still not to the level of my own knife, and he was happy with them. Took two and a half hours though, where sharpening my knife took me about 15 minutes.


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## psfred (Sep 2, 2014)

I did a couple knives for a friend, one of which I wish he would bring back so I could finish it, the tip wasn't really sharp.

You will cringe twice when you get a 20 x magnifier and take a look at the edge produced by a pull through sharpener!

Peter


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## Keith Sinclair (Sep 5, 2014)

Since your Mercer has only seen the stones, abused blades with comparable steel need more work, probably rounded edges with dings etc. Either a course stone or diamond plate to thin it out so you can kick in a final bevel on a medium stone.

A LED light at least 10X mag. is a good idea to see what you are up against. When I sharpened at work would do it at end of shift. At time maybe sharpening 4 knives & other cooks want me to sharpen theirs as well end up doing 8-10 knives. It seems to be a hazard of having sharp knives. Have taught quite a few cooks how to sharpen. Having them depend on you to do their sharpening is not serving them .If they do own, knives get trained to their style & touchups easier. If they are too cheap to get own stone & lazy to learn freehand let them use dull knives. Why wear down your stones.


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## LKH9 (Sep 6, 2014)

You can just use a cheap hardware store silicon carbide stone for those cheap cooks' knives. Save the expensive stones for yourself.


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## CutFingers (Sep 6, 2014)

Yes...and those cheap hardware stones are actually pretty good for adding a toothy wire that the cooks can pretend to sharpen when steeling


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## Keith Sinclair (Sep 9, 2014)

LKH9 said:


> You can just use a cheap hardware store silicon carbide stone for those cheap cooks' knives. Save the expensive stones for yourself.



I always kind of discounted those things. Some people buy them at the hardware store cuz lack of knowledge of better stones. I guess they could be used for thinning behind the edge then finishing off with a medium whetstone.


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## LKH9 (Sep 9, 2014)

These stuff are made for cheap knives. It will scratch a delicate Japanese knife even if you use it for thinning, I guess. It's great for opening a new edge, then switch to a quality finishing stone for the final edge. I have a good finishing stone for my cheap knives. Just using that hardware stone won't give you a fine edge, you need at least 1 good stone, yes.

Actually a good quality silicon carbide stone is quite good, there are some 'made in China' silicon stones here that feels and looks like crap at the first sight.


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## daveb (Sep 9, 2014)

Pls post a link to a good hardware store silicone carbide stone. My hardware store does not know what I'm asking for.


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## LKH9 (Sep 10, 2014)

I buy them locally. I can use this stone forever.


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## Benuser (Sep 10, 2014)

Would the term carborundum perhaps be more familiar?


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## daveb (Sep 10, 2014)

LKH9 said:


> I buy them locally. I can use this stone forever.



I'm curious. You recommend these stones so frequently I wondered how/where someone could buy one. Malaysia looks beautiful but would be a long road trip and I'm certainly not flying there.:whistling:

@Ben, Don't know that term either. Does JCK sell them? Thanks.


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## Benuser (Sep 10, 2014)

daveb said:


> Ben, Don't know that term either. Does JCK sell them? Thanks.


 Never seen with JCK.


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## LKH9 (Sep 10, 2014)

According to the packaging, it's made in Mexico. I highly recommend this because I've been using it to great effects on cheap knives. It's the same material used in grinding wheels and wet-dry sandpaper, great grinding material. It has 2 sides, coarse and medium. I use this stone dry when doing minor touch-ups.

I believe these are the similar stuff, but much more expensive and available in much higher grit. I've wanted to try their fine hone, but can't bear the shipping cost.:shocked3:
https://www.razoredgesystems.com/hones/hones


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## Pensacola Tiger (Sep 10, 2014)

daveb said:


> Pls post a link to a good hardware store silicone carbide stone. My hardware store does not know what I'm asking for.




Norton has one:

http://www.amazon.com/dp/B0001MSA5Y/?tag=skimlinks_replacement-20

or go real cheap:

http://www.amazon.com/dp/B006ZC6UZG/?tag=skimlinks_replacement-20


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## Ruso (Sep 10, 2014)

I just discovered that Norton and LKH9's stone (Carborundum) belong to the same Company: Grupo Saint-Gobain
However it looks like the Carborundum "line" is more focused on Latin America based on my minimal research.


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## Benuser (Sep 10, 2014)

The Saint-Gobain Groupe is rather a big player in glass and ceramics.


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## Keith Sinclair (Sep 10, 2014)

Man I would not want to put my knives on those things. One says has oil in the stone already. Oil & water do not mix. Even my old mans carbon wood chisels, have over 100 of them sharpen with a high quality waterstone. He sharpened them with Arkansas oilstones as a pattern & model maker mostly for windtunnels NACA & later NASA from 1939 to beginning of space shuttle when he retired. He was turning bowls into his 90's using Japanese blue steel turning chisels. Sharpened them using waterstones which he came to appreciate in his old age.


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## Benuser (Sep 10, 2014)

I've used them for profile and geometry correction and fingerguard removal with vintage carbons. If you keep them really wet -- with water -- you shouldn't get deep scratches. Anyway, for normal sharpening I wouldn't use them either, except for fast and dirty sharpening of soft stainless with a lot of pressure.


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## Keith Sinclair (Sep 10, 2014)

Well that is a way to remove fingerguards with out danger of overheating heel area using power tools. Maybe thinning option for dull cheap soft stainless.


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## LKH9 (Sep 10, 2014)

Just saying that you don't need Japanese waterstones for grinding cheap stainless/carbon knives, it's a painful thing to do. Reserve those precious stones for delicate Japanese knives only, as it will scratch and chip a high hardness blade.

Just don't buy the 'made in China' ones. When I just bought that stone, it was dry, not oily at all.


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## psfred (Sep 10, 2014)

Cheap stainless sharpens just fine on waterstones with light pressure. The edge doesn't last very long, but that's not due to the stones, it's the crappy stainless that folds over at a hint of pressure.

I've never found a use for extremely coarse India stones, anything I'd do with them I do with a pink wheel on my bench grinder, and someday I'll get a low speed one and eliminate the risk of burning things.

No point in doing things by hand when it's just material removal.

Peter


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## LKH9 (Sep 10, 2014)

psfred said:


> Cheap stainless sharpens just fine on waterstones with light pressure. The edge doesn't last very long, but that's not due to the stones, it's the crappy stainless that folds over at a hint of pressure.
> 
> I've never found a use for extremely coarse India stones, anything I'd do with them I do with a pink wheel on my bench grinder, and someday I'll get a low speed one and eliminate the risk of burning things.
> 
> ...



What I mean by painful is, Japanese waterstones are very expensive, and precious, using them just to grind a cheap stainless is a total waste of money and material.:no: 

Silicon carbide stone cuts very very fast on cheap stainless blades, it's easy to do that just by hand. I once even brought a totally dull heavy cleaver back to action just by freehand grinding on this stuff. Bench grinder(aka knife destroyer)?:no: This is what sets us different from other 'professional' sharpeners.


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## psfred (Sep 12, 2014)

I got very nice edges on some soft stainless for a friend. Don't know how long they will last, but when they went home they sliced carrots with minimal work. They will be back, I suppose, but sharpening is sharpening.

I gave up on oilstones ages ago, way too much work and way to little feedback. Waterstones are only expensive if you don't figure the time and frustration. I don't anticipate wearing mine out in my lifetime -- I'll put up with the mess and flattening requirements in exchange for the much better and longer lasting edges. 

Rather than sharpen soft steel knives on the sidewalk, I'm getting decent quality hard steel knives - a much better state of affairs. I'll probably be getting my friend a gyuto for christmas in the next few years.

Peter


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## LKH9 (Sep 12, 2014)

Silicon carbide is not oilstone, it's a totally different species.


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## Ruso (Sep 12, 2014)

> Silicon carbide is not oilstone, it's a totally different species.


I tend to disagree. Oil stone is quite a broad definition. And to be honest oil stone does not mean much. The name just hint's that the stone is suitable to be used with oil. However water, soapy water or dry are acceptable uses as well. The material the stone is made does not per se define it as Oil stone.
Some info:
http://www.sharpeningsupplies.com/Difference-in-Sharpening-Stone-Materials-W51C116.aspx


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## LKH9 (Sep 12, 2014)

Ruso said:


> I tend to disagree. Oil stone is quite a broad definition. And to be honest oil stone does not mean much. The name just hint's that the stone is suitable to be used with oil. However water, soapy water or dry are acceptable uses as well. The material the stone is made does not per se define it as Oil stone.
> Some info:
> http://www.sharpeningsupplies.com/Difference-in-Sharpening-Stone-Materials-W51C116.aspx



He should just try it first before saying it's useless. Next to diamond, silicon carbide is the fastest cutting stone, it's manufactured by melting the sand to get them bond together.


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## Ruso (Sep 12, 2014)

LKH9 said:


> He just just try it first before saying it's useless. Next to diamond, silicon carbide is the fastest cutting stone, it's manufactured by melting the sand to get them bond together.



I think we talk different languages here mate. I beg your pardon, but WHAT, where does the above come from?


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## psfred (Sep 12, 2014)

Boron carbide is harder, I think, but we are talking very minor differences here. Silicon carbide often goes "blunt" fairly quickly as the corners chip off the cubic particles, making a hard bonded stone "dull" quickly and cut slowly. Aluminum oxides do the same thing, but in a softer bond (i.e. waterstone) fresh abrasive is exposed as the worn abrasive gets rubbed off when it dulls. Hard bonded stones, like "oilstones" don't shed grit easily because it's fused together with some sort of ceramic binder, just like grinding wheels and other similar tools. Works well when cutting speed is secondary to shape retention of the grinding surface, but that's not really an issue with knives.

Diamond may cut fast, but coarse diamond has it's drawbacks too, especially that it makes deep scratches with very very high localized pressure, which can cause micro-cracking on very hard steels if used with a heavy hand. Hard bond silicon carbide can do the same thing in very coarse grades. Neither in a hard bonded form will give the polish a waterstone will, etc. 

Peter


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## LKH9 (Sep 12, 2014)

@Peter, which is why I always say it's made for cheap, soft stainless knives, it's just a compliment pair, Hard stone + Soft crap knife. I won't touch any precious hard Japanese blades on it either. When I thinned out a pair of Japanese-style carbon scissors(similar geometry as Japanese single bevel), I could see how badly it scratched out the blade. Soft waterstone is designed to polish and not chip a hard Japanese blade. Another thing that will micro-chip a hard blade is the floating steel particles, unless you use the oilstone dry.

Japanese waterstone is very specialized tool, not a general purpose sharpening stone.

BTW, quality silicon carbide stones only cost 1.4USD here, shipped all the way from Mexico and still this dirt chip, I think those sold online are rip-offs.


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