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Equipment & Gear: Knife and Sharpening Steel Hardness
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gowings
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PostPosted: Fri Mar 19, 2010 9:09 pm    Post subject: knife sharpeners Reply with quote

Hello. I'm kind of late to this discussion but wanted a recommendation on knife sharpeners (steels and strops will come later). I use a Lansky and have borrowed a Syderco sharpener. I prefer the Lansky because of the stone-edge angle being maintained in my novice hands (blade clamped in bracket with stone on guided rod, captured in a bracket guide hole). The Spyderco (free hand keeping blade vertical, drawing down angled rods) left too much room for error, for my tastes. Problem is each of these takes quite a bit of time to go through our sets a few times per year. I understand sharpening frequency may be decreased with steeling/stropping but until then can anyone suggest a powered sharpener which will yield good results? -Thanks.
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Dilbert



Joined: 19 Oct 2007
Posts: 1018
Location: central PA

PostPosted: Fri Mar 19, 2010 10:12 pm    Post subject: Reply with quote

most knife nuts don't recommend "power sharpeners" -

blink and you've got a ruined dinged up gouged out knife edge.

in use the really pointy part of the cutting edge will bend over, wear down, etc.

steeling 're-aligns' the cutting edge - that is if it is rolled over, it straightens it out - if using a grooved/pebble type steel, the steel can remove a minor amount of metal to 'restore' a sharp bit to the edge.

stropping 'polishes' the cutting edge to an even finer 'thickness'

unless you're doing 1 mm thick sushi slices or insist that a grape dropped from 1/2 inch must slice through under its own weight, stropping is likely a bit overboard for the average user.

Lansky and EdgePro are two very well respected names in the 'knife sharpener gizmo' business.

>>go through our sets a few times per year.

at a loss... "sets"? are you attempting to resolve a 'home use" issue or a 'commerical kitchen/restaurant' issue?

I have some ten knives in fairly heavy/active home use - 10 inch to 3 inch - I freehand sharpen using a medium and a fine stone - I break out the stone and check/sharpen them twice a year. I use a grooved steel per manufacturer item # for in between and I don't abuse the knives.

may take 45-60 minutes to 'go thru the set'

once you've got the Lansky system "setup" and having two smidgens of practice, really should not take all too long to put a good edge on a knife.

unless of course they're abused, used to hack open tin cans, bash bones, chop up glass cutting boards....and the like.
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gowings
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PostPosted: Tue Mar 30, 2010 7:05 pm    Post subject: sharpeners Reply with quote

Thank you, Dilbert. I'll also check the Edge Pro. Thanks also for helping me understand the difference between stropping and steeling.
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BLouis79



Joined: 12 Apr 2010
Posts: 1

PostPosted: Mon Apr 12, 2010 11:52 am    Post subject: Reply with quote

My preferred major sharpening method is by hand using a flat diamond stone. Oilstones work well but their wear causes problems with flatness over time that diamond stones do not suffer (more important with flat blades like chisels and planes).

Steels are recommended for daily light use. The diamond stone gets used once a year or so whenever bluntness becomes annoying.

In a pinch (eg on holidays), the unglazed fine ceramic edge of a bowl or mug base is a great sharpener if no others are available. Grandfather and mother used to use that method.

Angle of the knife edge makes a big difference to performance - a blunter angle resists damage, a more acute angle improves sharpness at the expense of edge fragility. Beyond that a slightly curved bevel profile more like an axe is probably optimum as opposed to a single angle to the blade face.

I'm wary of ceramic or sapphire coated rods which will remove metal and alter the knife blade shape at the point of first contact.
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Jim Cooley



Joined: 09 Oct 2008
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Location: Seattle

PostPosted: Mon Apr 12, 2010 2:32 pm    Post subject: Reply with quote

I'd just add that it took me years to realize that couple swipes on a steel does wonders for an already sharp knife. So if you're not in the steel habit, I'd give it a test.
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Dilbert



Joined: 19 Oct 2007
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Location: central PA

PostPosted: Mon Apr 12, 2010 4:04 pm    Post subject: Reply with quote

Jim -

do you use the steeling toward the body or away from the body technique?

I never felt comfortable steeling toward me, so for years I used the steeling away technique. then I decided I was going to master the technique of flashing knives and singing steel and worked on steeling toward the body.

It could certainly be my imagination, but I think it gets better results - the edge seems sharper steeled toward the body than away. the "geometry" of the situation says 'it's the same' but there must be other factors - consistency of angle / pressure / whatever that is different. might take some hi-speed video ala MythBusters to 'document' it tho . . .
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Joe Marfice
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PostPosted: Thu Nov 11, 2010 6:11 am    Post subject: Honing, not grinding the edges Reply with quote

The discussion here seems partly focused on grinding a new edge on one's knives, which sadly is the case on most knife forums. In reality, this is rarely what your knife needs (unless you've damaged it by trying to cut something too hard).

Honing - drawing the blade edge along a honing steel - will only remove a neglible amount of steel, if any, and is what a dull knife needs 95% of the time. I have 4-5 knives I use on a daily basis, doing everything from cutting twigs to butchering small game, and I probably regrind edges on a stone no more than once a year per knife (except for my pocket knife, that I abuse...).

Honing is the act of straightening the nearly microscopic bend-overs at the very edge of the knife. It does not require removal of material. In fact, a perfectly smooth honing steel would probably work as well as a grooved steel, but I've never seen one. The bottom of a coffee cup (unglazed porcelain) is a perfectly functional hone (though it does grind away tiny bits of steel, but this is trivial: its real efficacy is through honing). I have a cheapo $10 steel, and it sharpens - hones - my $90 Henckel Twin Chef with ease. It only has to be harder than the knife; "superlative craftsmanship and balance" are a pretentious waste of $$$ on hones.

Instead of wondering which high-tech, high-cost sharpening system to use, buy a cheap hone (or grab the steel you probably already own), and slowly, gently, stroke the edge into line. Three strokes on the left, three on the right, repeat, repeat, quit. Gentle - you don't want to overbend the metal to the other side! The amount of metal you're trying to bend is tiny - added pressure is probably too much. Slow - the showy swish!swish! motions you see most people use are sloppy, and you can't bend something straight with sloppy moves.
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Joe Test
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PostPosted: Thu Jul 07, 2011 12:34 am    Post subject: Damascus Steel Reply with quote

I found a source of low cost Damascus steel kitchen knives. I think I can get a Chef's knife for under $100. The manufacturer asked what hardness I wanted and I thought Rockwell 85 sounded good per your analysis. I won't be able hold or examine the knife before it arrives, is there anything I should look out for?

Thanks!
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Jim Cooley



Joined: 09 Oct 2008
Posts: 338
Location: Seattle

PostPosted: Thu Jul 07, 2011 3:35 pm    Post subject: Reply with quote

Dilbert wrote:
Jim -

do you use the steeling toward the body or away from the body technique?

I never felt comfortable steeling toward me, so for years I used the steeling away technique. then I decided I was going to master the technique of flashing knives and singing steel and worked on steeling toward the body.

It could certainly be my imagination, but I think it gets better results - the edge seems sharper steeled toward the body than away. the "geometry" of the situation says 'it's the same' but there must be other factors - consistency of angle / pressure / whatever that is different. might take some hi-speed video ala MythBusters to 'document' it tho . . .


Could it be that the edges of the steel itself are worn when you steel "away" but not when you steel "towards" you?

I have two steels, and usually use the old worn one because the newer one seems just a bit too coarse.
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Dilbert



Joined: 19 Oct 2007
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Location: central PA

PostPosted: Thu Jul 07, 2011 4:42 pm    Post subject: Reply with quote

Jim Cooley wrote:

Could it be that the edges of the steel itself are worn when you steel "away" but not when you steel "towards" you?

I have two steels, and usually use the old worn one because the newer one seems just a bit too coarse.


dunno - my steel is round, so an edge on the steel itself isn't 'possible'

in both cases, the stroke is 'into' the knife edge - the only difference I can detect is the angle of the knife-to-steel is more perpendicular stroking away from the body - stroking toward the body the angle seems more acute...
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Dilbert



Joined: 19 Oct 2007
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Location: central PA

PostPosted: Thu Jul 07, 2011 4:46 pm    Post subject: Re: Damascus Steel Reply with quote

Joe Test wrote:
I found a source of low cost Damascus steel kitchen knives. I think I can get a Chef's knife for under $100. The manufacturer asked what hardness I wanted and I thought Rockwell 85 sounded good per your analysis. I won't be able hold or examine the knife before it arrives, is there anything I should look out for?

Thanks!


85R would be about 'normal' - a lot of the Japanese style knives are a couple points harder - this in theory allows a finer edge when stoned/polished/stropped to the nth degree - but the downside to the hard thin edge is: "oops, it chipped!" . . . and that does happen.

as for the rest - basically you're left with the knife maker's reputation -
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Jim Cooley



Joined: 09 Oct 2008
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PostPosted: Fri Jul 08, 2011 3:31 pm    Post subject: Reply with quote

Dilbert wrote:


dunno - my steel is round, so an edge on the steel itself isn't 'possible'

in both cases, the stroke is 'into' the knife edge - the only difference I can detect is the angle of the knife-to-steel is more perpendicular stroking away from the body - stroking toward the body the angle seems more acute...


Doesn't your steel have tiny vertical ridges running down its length? Mine do.

Say I'm holding the steel in my left hand. When steeling away from myself, the knife would contact the left edge of the ridges; and vice versa if I were steeling toward myself.
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Dilbert



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Location: central PA

PostPosted: Fri Jul 08, 2011 3:57 pm    Post subject: Reply with quote

>>groves -

yes - see what you mean - need to take the mag glass to the steel and see if I can detect any geometry differences....
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essentialfoodstorage02
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PostPosted: Mon Aug 06, 2012 7:56 am    Post subject: sharpening knives Reply with quote Delete this post

Well, it is better to keep your kitchen knife sharp as possible to avoid ruining your recipes and your cooking skills, too... thanks for sharing this stuffs... it's a good help for me especially now that I am planning to cook some fresh sushi....or maybe tomorrow...
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