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cwrightthruya
07-25-2012, 12:38 AM
So, I did a search and could not find a consolidated thread on the subject, so I thought I would start one...but then again, I am blind so if there is already a thread then please forgive me.

So what prompted this you might say:

In the past few weeks, I have had a few people send me J-nat stones to evaluate, each for different reasons. In essence, all were unhappy with their performance, and after numerous attempts to make things go the "right way", all were ready to give up.

This should never happen....
One should never become so frustrated with a subject that is supposed to bring joy and a feeling of accomplishment that they are ready to throw in the towel and move on to something else.

So, upon evaluation of the stones and the knives they were trying to sharpen, several problems became evident, which I will not go into, but this prompted me to start thinking about my own journey through sharpening, from synthetics to J-nats, from the EP to free hand sharpening. One thing is for sure, I made lots of mistakes, and even still continue to fix errors in my technique on a regular basis. But, I thought it would be nice if everyone could get together and pool some knowledge about their sharpening experiences. Specifically, talk about their mistakes, glaring or subtle, with the hope that it could turn into a great resource for anyone who may be having trouble.

I will go first with something simple, elegant, and very very necessary.

Make sure your stones are well lapped and well dressed.

I know it may seem like common knowledge to everyone, but even I fall into this trap on occasion. And 3 of the 5 stones I recently evaluated also suffered from it.
It is easy to be excited about a new stone and forget to completely lap it before taking it out for a test sharpen, which is apparently what happened to several of my newfound friends. Once I spent 20 minutes lapping the stones, something that had apparently never been done, they were actually amazing!!!

So who is next?

JBroida
07-25-2012, 01:16 AM
keep your stone surface wet (more so with sythetics, but also with naturals... just that water control is more important with naturals and with synthetics you can just toss water on as you please)

Sara@JKI
07-25-2012, 02:24 AM
some of the stones can't stay in the water forever... they can be mushy and break off... so make sure what type of stones you have!

Eamon Burke
07-25-2012, 04:04 AM
I honestly think the #1 mistake is Trepidation. Most of the poor sharpening I've seen is rooted in fear of inadequacy.



But also not holding a low enough angle to get the most out of a good knife. I don't concern myself with angle numbers, but on the nice steels we all pay for around here...they can take it. Go LOW.

Cutty Sharp
07-25-2012, 08:40 AM
Clean your knife off, even your hands too, when going up to a higher-grit stone - especially if it's a big grit jump. You probably won't want your old coarser particles mixed together with the finer ones on your next stone. ... I used to forget.

bieniek
07-25-2012, 09:43 AM
HM.
I never lap my stones to flatten them. I just dont have to
I occasionally do it to clean my JNS 1K, if I used it to sharpen stainless, which clogs the stone up like hell.
I just use the whole surface of the stone, especially when im polishing.
Most definitely it does not produce wavy bevels.

My mistake was oversharpening. I was trying to put 10K edge on everything, even on my butterknives. But Im cured off it now.
My mistake was to get multi-stone synthetic setup, which was for most part useless.
My mistake was to believe 3 strops with some funky compounds will make any noticable difference. But Im cured off that also.

shankster
07-25-2012, 10:03 AM
<My mistake was oversharpening. I was trying to put 10K edge on everything, even on my butterknives. But Im cured off it now>

Agreed!
I turned a 240mm gyuto into a 240mm suji in about a year looking for that "ultimate edge"..good practice though.

Birnando
07-25-2012, 10:57 AM
Snip...
My mistake was oversharpening. I was trying to put 10K edge on everything, even on my butterknives. But Im cured off it now.
Snip...

Aye, I'm definitely guilty of that. Still am I'm afraid.
Not a single one of my knives are honed to less than 20K...
What can I say, I just like to hone, and my honing background from the straight razor scene is hard to shake:)

Once I get a few more knives to practice on, I'm gonna have to try out those coarser grits as finishers on some of my edges.

mainaman
07-25-2012, 11:20 AM
#1 I can't believe anyone would try to sharpen on a natural stone that is not properly lapped before the first use. Those stone have been sitting in piles in back rooms for years and need a good lapping to clean up the surface and oxidation to get to fresh grit.

#2 using a ton of synthetics in progression is just not working well for me. I find it sufficient to use 1/6k and that is it. the same effect can be achieved with naturals only the refinement is higher.

#3 no need to sharpen for 30 min just to refresh the edge, over working the edge does not produce better results.

#4 one strop is enough, no need to have all the fancy compounds to try to get an edge that can peel a tomato with the weight of the blade only, those are nice tricks but that kind of edge is gone the moment the knife touches the board.

TB_London
07-25-2012, 12:23 PM
#1 don't move to the next stone until you've got it sharp
#2 check your edge for residual burr and wire edges
#3 watch where you are applying pressure

bkdc
07-25-2012, 12:30 PM
Agreed!
I turned a 240mm gyuto into a 240mm suji in about a year looking for that "ultimate edge"..good practice though.

I think we've all done this. ^_^

jgraeff
07-25-2012, 01:50 PM
My mistake was moving too fast in different ways

First actually moving fast on the stone with the knife. I found if I go slower I'm more accurate.

Second moving to things like thinning, changing angles etc before I had basic sharpening down.

Lastly not understanding pressure. Once I started to get pressure down I was getting a lot better edges.

Lefty
07-25-2012, 03:51 PM
Overthinking.
I do everything by feel (which can bite me in the ass, at times), from cooking, to golfing, to sharpening. I'm sure if you ask Jon, Dave, Chef Ma, etc, they just let their hands do what they naturally do and switch stones when it feels right.

cwrightthruya
07-25-2012, 04:32 PM
Not asking enough questions, either from fear of looking bad or from stubbornness.

zitangy
07-25-2012, 11:33 PM
Clean your knife off, even your hands too, when going up to a higher-grit stone - especially if it's a big grit jump. You probably won't want your old coarser particles mixed together with the finer ones on your next stone. ... I used to forget.

My cleaning stone and also for making slurry is a smaller 1000 grit stone. Doesn't not bother me abt cross crosstamination as I expect it to leave 1000 striations + the 3000 and 5000 grit striations.

Only when I am polishing traditional single sided knives.. at 10.000 grit.. i look for a seasoned small diamond plate.., hopefully no loose diamond particles comes off from it

hv fun..
D

Sara@JKI
07-26-2012, 04:05 AM
how about... counting strokes and not paying as much attention to the burr. Counting strokes probably helps a bit to sharpen evenly along the edge, but each stroke won't be perfectly precise (in terms of pressure, angle, etc), so just taking a count wouldn't be enough.


(Says a girl @ JKI who is about to make sharpening mistakes on Friday.)

Benuser
07-26-2012, 06:54 AM
Being afraid of coarse stones. With some steels you will never have a stable edge until you set or refresh the bevels on a medium coarse one (J400 or so). It was Dave who explained this regarding AS.
Other consequence: you stick with fatigued steel.

Cadillac J
07-26-2012, 11:54 AM
Being afraid of coarse stones. With some steels you will never have a stable edge until you set or refresh the bevels on a medium coarse one (J400 or so). It was Dave who explained this regarding AS.
Other consequence: you stick with fatigued steel.

This concept gets lost on many, but I agree completely.

I remember always hearing to use the highest grit stone you can get away with depending on the state of the edge at hand, as to not remove too much steel. However, its not like going to a coarser stone, or grinding just a bit longer on same stone is going to have that much of a difference.

Not to mention, edge retention has increased every knife/steel since I've kept this in mind when sharpening. Get rid of the fatigued steel people (don't need to on touch ups/maintenance though)

Justin0505
07-26-2012, 03:21 PM
You dont need a 50 stone progression: you should be able to go from dull to very sharp using just 2-3 stones. Unless you're gping fpr a certain look or mirror polish, you don't need to remove all of the scratches from the previous stone before moving onto the next so dont spend too much time on each stone

tk59
07-26-2012, 03:53 PM
I'm not sure if anyone mentioned this yet but after seeing many, many knives even from experienced forum members, people tend not to spend the same amount of time on all areas of the edge, leading to wierd profile changes, overgrinds in front of the heel and behind the tip (holes in the edge). Most folks need to ease up on pressure and work the entire length of the edge more or less equally unless they are shooting for a particular profile.

JBroida
07-26-2012, 08:20 PM
I'm not sure if anyone mentioned this yet but after seeing many, many knives even from experienced forum members, people tend not to spend the same amount of time on all areas of the edge, leading to wierd profile changes, overgrinds in front of the heel and behind the tip (holes in the edge). Most folks need to ease up on pressure and work the entire length of the edge more or less equally unless they are shooting for a particular profile.

+1... using visual and tactile inspection you can keep track of this a little better (i.e. forming the same size burr across the entire edge and keeping even and consistent bevels)

mhlee
07-26-2012, 09:38 PM
Argh. Now I'm thinking of a bunch of questions I should have asked at the WCG when Jon and TK were there.

Then again, it's not like I would have had much of a chance to sharpen with three or four people always sharpening at the same time and on different tables! :knife:

bieniek
07-27-2012, 01:56 AM
Being afraid of coarse stones. With some steels you will never have a stable edge until you set or refresh the bevels on a medium coarse one (J400 or so). It was Dave who explained this regarding AS.
Other consequence: you stick with fatigued steel.

Thats why I dont really get it, why not remove the used up steel with diamond plate? Phuck coarse stones. They dish.
I do that.
I dont call it sharpening, its removal of excess metal.
I use my 1K for sharpening later on, when the bevels are roughly set.

gregg
07-27-2012, 08:52 AM
This is a very good thread; I think it might be good to "umbrella" it with Dave's Sharpening questions thread; all the no-no's (apostrophe?), and the oui-oui's, (sorry, I live in France; plus oui-oui is funny!), in one Library of Congress for k-nuts. My only contribution to this one is that when it isn't happening, in spite of pulling it off on numerous past occasions, if you have the time, WALK AWAY for a few minutes, smoke a cigarette, if you still engage in that nasty habit like I do, and come back with a new outlook, and dry hands! Dry hands; that really helps! Otherwise, sharpen other peoples knives to avoid ending up with knitting needles that used to be your favorite gyuto!