Different grits for different tasks

[GorillaGrunt]

I have been sharpening in a pretty elementary way, using a 400 if I really need to, then a 1000, then a 6000 for every knife, maybe stropping on newspaper. I use different angles and microbevels depending on the steel and the blade type, but recently I've been reading that some knives shouldn't be sharpened to even 6k depending on the use. Specifically, there was something somewhere about better edge retention by not exceeding 3-4k on knives used for fatty meat or fish. Also, I've heard preferences for "toothy" edges and that cooked proteins and smooth-skinned vegetables are cut better with a less polished edge. Can someone give me some insight on this?

Further question: in a professional environment (cooks trained with Western cutting technique using s____y plastic boards) can I get a longer-lasting edge by doing something other than sharpening to the highest available grit?

Thanks

 

[labor of love]

It's completely up to you. I tend to keep my petty, suji, and gyutos that I use for rougher work with a 4K edge, then other stuff at 6-8k. Edge retention isn't in the equation at all for me, it's just a matter of if I want more refinement or more of a toothy bite in the finishing edge.

 

[mark76]

I recently read an article about this.
The point of the article was that coarse edges (up to a point) have a longer edge retention than fine edges. Although this has been stated more often (and I didn't always agree; how do you measure this longevity?), I had never seen a good reason for this. The hypothesis in this article was that the teeth of a coarse edge break off easier than those of a fine edge, thus keeping the edge sharp for a longer time.

Unfortunately I cannot find the article back. Does anyone have a link for me and perhaps the OP? Thanks!

 

[mcritchlow]

It's completely up to you. I tend to keep my petty, suji, and gyutos that I use for rougher work with a 4K edge, then other stuff at 6-8k. Edge retention isn't in the equation at all for me, it's just a matter of if I want more refinement or more of a toothy bite in the finishing edge.

I totally agree with this. And my preferences have changed over time. When I first started sharpening, I wanted (or thought I wanted) the most refined edge possible (6-8k). I think part of that was liking the fancier looking finish as well, as if I had done a "better" job or something. Did it on every knife.

Now I finish the edges on my knives, almost exclusively, with a stone that's in the 3-5k range (Gesshin Synthetic Natural) and I like the feel of the edge much better. I don't know that I'd speculate as to whether edge retention is in any way improved, but I like the increased tactile feedback.

 

[paper-crane]

Cliff Stamp did some research on this rather complex issue. I'll try to summ it up:
A more coarse finish will have much higher edge retention but ONLY on a slicing cut / sawing motion.
A finer finish will encounter much less resistance (as in produces better ease of cutting) in a push cut.
(Picture this: you don't use an axe for sawing or a saw for chopping through blocks of wood...)
However let's keep in mind that a lot of things influence "sharpness" and edge retention: the materials cut, the cutting technique, the board, the quality of the edge produced through sharpening (e.g. a burred edge will have non-existent edge retention, a stressed edge / fatigued metal on the edge will have horrible edge retention), the thickness and angle of the final edge apex (as in a thinner edge has better edge retention).

Hope I could help,
PC

 

[GorillaGrunt]

For my own knives, edge retention is a non-issue; if they need a touch-up I do so even if it's only been one shift. For my coworkers' knives, though, I'd like the edges to last a little longer. Of course there are plenty of factors over which I have no control, such as the knives themselves, other people's technique, the cutting boards, and so on, but if there's something I can do to make my sharpening more practical and more helpful I'd like to do so.

I've had my eye on the GSN stone as possibly my next stone. I get a very sharp edge from the 6000 that suits me and my cutting style just fine, but on the other hand I haven't tried anything else.

 

[labor of love]

GSN stone?

 

[GorillaGrunt]

Gesshin Synthetic Natural

 

[labor of love]

Gesshin Synthetic Natural

Oh yeah. I want one too.

 

[Yoni Lang]

Definitely depends on what you're cutting! For fish I prefered to fillet with my knife around 3k grit, MAX 4k. Too high while you're breaking something down and you lose your sense of control. You start cutting into things you don't want. Having a sharp knife with a little "drag" always helped for fish. Slicing the fish afterwards I preferred the highest possible (in my case 8k). If you're doing veggie work including tomatoes then the toothier the better (i'd say 2k max). All stones are not created equally though so you might get a sharper, more polished knife from a certain 3k stone then you do from another 3k stone. Just get used to your stones. I also found that a deeper microbevel on my knives would generally help with edge retention through a long day of prepping.