# Edge dull too fast?



## blokey (Apr 6, 2022)

I have been recently doing a lot of sharpening, changing my techniques, learning from JKI's playlist. I usually go from SP1000, then ouka 3000, depends on the steel type I might do some light stroke against a SP5000, and use a leather strop to finish them off. The edge bevel is usually below 15 and I use a Hasegawa FSB for chopping. I have been able to clean cut paper towels with the fresh edges, something that I wasn't able to do before, but it cuts like a dream. But seemingly just after one cutting session, the edge would struggle against paper towel, and after couple more they would not able to chop tomatoes into very thin slices smoothly as they do with fresh edges. The knives would not go straight through tougher pepper and roma tomatos without some slight gliding, other thins cuts just fine though. 
Is something wrong with my techniques or is it my expectation too high? Seems to me the edge dulls rather quickly against tough skins, I can bring them back with quick stropping but I do hope for more.


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## blokey (Apr 6, 2022)

BTW but fine chopping tomato I mean something like this, I do more push cuts tho.


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## Benuser (Apr 6, 2022)

Rapid dulling has often to do with incomplete deburring. The remaining burr breaks off and leaves a moonscape-like edge behind. Or it folds over the edge and makes it perfectly dull, as happens with soft steel. Tell us which knives are concerned. Do you deburr after every stone in the progression, and how do you deburr?


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## Walla (Apr 6, 2022)

I'll second the burr problem... your comment that stropping brings back the edge really makes me think that's what is going on.

Often when people get to the point they are holding consistent angles they end up with what is often referred to here as a wire edge (it has been debated whether it exists or if it is the correct term...but I'm a believer because it happened to me a while back...)

When it happens...very carefully feel the edge to see if you can feel it rounded over...check it the way you'd feel for a burr while sharpening...you feel it... then you need to look into burr removal techniques... fortunately there are several methods you can easily find on here...find the one that works for you...

Should that not be the case...try finishing on a 1k ish stone see if the issue persists...there is an outside chance that when you hit the higher grits you are over working or over refining the edge and your technique needs adjusting...

Let us know how it works out...

Take care

Jeff


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## Jovidah (Apr 6, 2022)

Try a microbevel at slightly steeper angle? Could both solve microburr issues and increase edge stability.


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## branwell (Apr 6, 2022)

Would recommend taking a look at this site. Tons of scanning electron microscope images and articles showing what's going on with edges burs, etc.









Index


Quantifying Sharp Definitions of Sharp and Keen Sharp and Keen part 2 The Slice Cut A Comparison of Several Manufactured Blades The Bevel Set The Honing Progression The Diamond Plate Progression It…




scienceofsharp.com


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## M1k3 (Apr 6, 2022)

What kind of knife and steel?

Sounds most likely that you're not deburring properly. Possibly over doing it or not doing it right on the higher grits.

For tomatoes, I also find an edge around the 1k grit mark works best.


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## ModRQC (Apr 6, 2022)

Steel? What kind of cutting surface? Chopping motion used? How extensive the cutting session?

Obviously burr is probably the problem, but still, these above variables should be made clear so that we can assess the particular situation each time someone asks that.


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## blokey (Apr 6, 2022)

Thanks for all the advices!


ModRQC said:


> Steel? What kind of cutting surface? Chopping motion used? How extensive the cutting


I seems have more problems with white #2, Aeb-l and 52100 while SKD12 and R2 are ok. I use hasegawa FSB cutting board, mainly push cut, some chopping with white#2 nakiri. The chopping sessions aren’t long, just cutting whole carrot into sticks, some tomato and mushrooms.


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## blokey (Apr 6, 2022)

Benuser said:


> Rapid dulling has often to do with incomplete deburring. The remaining burr breaks off and leaves a moonscape-like edge behind. Or it folds over the edge and makes it perfectly dull, as happens with soft steel. Tell us which knives are concerned. Do you deburr after every stone in the progression, and how do you deburr?


I deburr after each progression, just light edge trailing strokes until I can’t feel the burr.


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## Barmoley (Apr 6, 2022)

Try the following, sounds like you might be creating a wire edge. Kippington Deburring Video


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## ModRQC (Apr 6, 2022)

blokey said:


> Thanks for all the advices!
> 
> I seems have more problems with white #2, Aeb-l and 52100 while SKD12 and R2 are ok. I use hasegawa FSB cutting board, mainly push cut, some chopping with white#2 nakiri. The chopping sessions aren’t long, just cutting whole carrot into sticks, some tomato and mushrooms.



This would rule out deterioration from acidity, AEB-L obviously and even 52100 is not so readily dulling from it and if only a few tomatoes in a short session.... Of course all three steels are those that have lesser retention, but one short prep is not that. 

What's more interesting is that "usually" you'd have more "difficulties" deburring SG2 or possibly SKD-12 than the other ones. So if a burr is your problem, it's probably something you do in the last where the simpler steels are more affected. 

I meant to ask if you tested/remarked that this happened with segments of the edge only, or the whole edge goes downhill no matter what?



blokey said:


> I deburr after each progression, just light edge trailing strokes until I can’t feel the burr.



I'd look into developping the edge leading deburring method. It COULD be that using trailing on the simpler steels you raise a very very small burr that would act very sharp for a very short time. MIGHT not happen with the other ones so readily, or not as prominently.



Barmoley said:


> Try the following, sounds like you might be creating a wire edge. Kippington Deburring Video



Beware that this creates a micro bevel. You might lose control/track of it in the future if you don't remember or pay attention to it.


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## Delat (Apr 6, 2022)

blokey said:


> I deburr after each progression, just light edge trailing strokes until I can’t feel the burr.



You might want to try edge-leading instead of edge-trailing for your finishing deburring strokes, at least for the last stone.


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## inferno (Apr 6, 2022)

yeah no trailing! only time i do trailing is when i have really, really soft stones. otherwise NO!
i would guess edge trailing on a fast stone like a shapton. even if its a 5k will definitely result in a small wire edge/burr.

aeb-l and 52100 are good steels if ht'ed correctly. they should last for more than one session.
good steel will probably stay sharp for a whole shift right? isn't that the common standard?

so you are probably doing something wrong. you just have to figure out what.


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## natto (Apr 6, 2022)

A nail test or flex test pushes weak material over to one side. If the knife shaves in one direction only some burr is left.


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## Kawa (Apr 6, 2022)

The way I read the opening post, hes asking if its normal to loose that super fresh sharpness after 1 session.
I do agree that you have a serious high level of sharpness for a long time, but that really fresh sharpness?

I havent tested a paper towel test or cutting tomatoes the way in the movie after a small sesion, so i wouln't know if i'd be still able to do that.

I know for sure that my white and blue steel loose that fresh sharpness very fast when doing tomatoes in the first session. They hold up very sharp afterwards.

So more a question from my side aswell:
After lets say after 15-20 minutes of prep work (short session?), is all of yours knives still as sharp as fresh of the stone/strop?


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## blokey (Apr 6, 2022)

Kawa said:


> The way I read the opening post, hes asking if its normal to loose that super fresh sharpness after 1 session.
> I do agree that you have a serious high level of sharpness for a long time, but that really fresh sharpness?
> 
> I havent tested a paper towel test or cutting tomatoes the way in the movie after a small sesion, so i wouln't know if i'd be still able to do that.
> ...


Just 15-20 minutes it is fine, won't be able to slice paper towels but still able to cut newspaper no problem, but sometimes it seems to struggle with tomato skins if I just saw them horizontally, but using guillotine and glide works fine.


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## ModRQC (Apr 6, 2022)

blokey said:


> Just 15-20 minutes it is fine, won't be able to slice paper towels but still able to cut newspaper no problem, but sometimes it seems to struggle with tomato skins if I just saw them horizontally, but using guillotine and glide works fine.






M1k3 said:


> ....
> 
> Sounds most likely that you're not deburring properly. Possibly over doing it or not doing it right on the higher grits.
> 
> For tomatoes, I also find an edge around the 1k grit mark works best.



I'd consider this to be rather normal. I also always found SP5K to be able to give a magical "ghosting effect" to an edge, but not one that would perform with waxy skins ever so well.


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## Infrared (Apr 6, 2022)

I exclusively use edge trailing and have never experienced the issues you're having,
My advice would be to simplify your sharpening session as much as you can to find the real problem.
Maybe try something like this (with your white steel):

Use SP1000 to raise burr on one side then the other.
Use reduced pressure and edge trailing like Peter Nowlan or edge trailing like Jon (both work fine).
Try nail bite test and paper towel.
If successful, move on to SP5000. If not, continue with edge trailing.
With light pressure, sharpen both sides like you did on the SP1000.
Edge trailing.
Nail test and paper towel.
If successful, continue to next step. If not, continue edge trailing.
Strop with denim (NOT leather).

Just curious. How long can you use your R2 knife before they need a touchup?


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## blokey (Apr 6, 2022)

Infrared said:


> I exclusively use edge trailing and have never experienced the issues you're having,
> My advice would be to simplify your sharpening session as much as you can to find the real problem.
> Maybe try something like this (with your white steel):
> 
> ...


Thank you! Will try, R2 last pretty long, I have a Takamura red handle and Kobayashi Kei, both would last at least a month before need any touch up, I don’t take them to high grit though like I do carbon steel.


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## ModRQC (Apr 6, 2022)

Infrared said:


> Just curious. How long can you use your R2 knife before they need a touchup?



Good question indeed. Or the SKD-12 one for that matter? Carbide volume helps SP5K adopt a bit more toothiness than it does simpler steels.


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## ModRQC (Apr 6, 2022)

blokey said:


> Thank you! Will try, R2 last pretty long, I have a Takamura red handle and Kobayashi Kei, both would last at least a month before need any touch up, I don’t take them to high grit though like I do carbon steel.



I think I get it now. If you want AEB-L, W#2 or 52100 to adopt that kind of behavior, I just don't think SP5K cuts the deal. SG4K would much better. Or a much cheaper Ouka which is also oh so forgiving/wonderful of trail deburring or just any technique and levels of skills whatsoever.


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## blokey (Apr 6, 2022)

ModRQC said:


> I think I get it now. If you want AEB-L, W#2 or 52100 to adopt that kind of behavior, I just don't think SP5K cuts the deal. SG4K would much better. Or a much cheaper Ouka which is also oh so forgiving/wonderful of trail deburring or just any technique and levels of skills whatsoever.


Thank you for all the help, I tried finishing using light edge leading stroke just on sp1k and the result fresh edge while not as screaming sharp but last a lot better after couple sessions, seems I have work my techniques on higher stones alot more.


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## blokey (Apr 6, 2022)

Infrared said:


> I exclusively use edge trailing and have never experienced the issues you're having,
> My advice would be to simplify your sharpening session as much as you can to find the real problem.
> Maybe try something like this (with your white steel):
> 
> ...


Thank you! Do you mind me asking why denim not leather?


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## ModRQC (Apr 6, 2022)

blokey said:


> Thank you! Do you mind me asking why denim not leather?



Because too fine an edge won’t help you. Denim is rough. SP5K + leather hoping to cut waxy skins even at home for a while is asking too much. You’re in the cutting delicate fish territory there. Not cutting into tomatoes about equally efficiently for 10 even short sessions. 

Don’t forget: your results might elevate your awareness of sharp, yet sustainably such sharp is why we all still dream of the dream steel.


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## blokey (Apr 7, 2022)

ModRQC said:


> Because too fine an edge won’t help you. Denim is rough. SP5K + leather hoping to cut waxy skins even at home for a while is asking too much. You’re in the cutting delicate fish territory there. Not cutting into tomatoes about equally efficiently for 10 even short sessions.
> 
> Don’t forget: your results might elevate your awareness of sharp, yet sustainably such sharp is why we all still dream of the dream steel.


Thank you, that make sense.


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## Kiru (Apr 7, 2022)

blokey said:


> I have been recently doing a lot of sharpening, changing my techniques, learning from JKI's playlist. I usually go from SP1000, then ouka 3000, depends on the steel type I might do some light stroke against a SP5000, and use a leather strop to finish them off. The edge bevel is usually below 15 and I use a Hasegawa FSB for chopping. I have been able to clean cut paper towels with the fresh edges, something that I wasn't able to do before, but it cuts like a dream. But seemingly just after one cutting session, the edge would struggle against paper towel, and after couple more they would not able to chop tomatoes into very thin slices smoothly as they do with fresh edges. The knives would not go straight through tougher pepper and roma tomatos without some slight gliding, other thins cuts just fine though.
> Is something wrong with my techniques or is it my expectation too high? Seems to me the edge dulls rather quickly against tough skins, I can bring them back with quick stropping but I do hope for more.


It might not be technique, chopping tomato requires quite a toothy edge, and as @ModRQC said, it's close to the fish cutting territory.
Maybe the edge will be able to perform the way you wish it does fresh off the stone, but after a session or two the edge loses it's toothyness(toothiness? Is that even a word?)
I personally have not used the SP 5K but I've heard the edge it gives isn't the toothiest in the range, so that doesn't really help either!

For task like so, I like to test my edge with Murray Carter's three fingers test to feel how toothy the edge is.
If not, I strop on my Aizu/Morihei 4K to bring back the teeth instead of strop, I personally think strop is great, but they take away the teeth on your edge after repeatedly touching up with it couple times, stropping makes my knives' edge smooth, especially with compound, that's only my opinion though, a lot more has to consider of course.


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## blokey (Apr 7, 2022)

Kiru said:


> It might not be technique, chopping tomato requires quite a toothy edge, and as @ModRQC said, it's close to the fish cutting territory.
> Maybe the edge will be able to perform the way you wish it does fresh off the stone, but after a session or two the edge loses it's toothyness(toothiness? Is that even a word?)
> I personally have not used the SP 5K but I've heard the edge it gives isn't the toothiest in the range, so that doesn't really help either!
> 
> ...


Might try leave the leather strop in the drawer for awhile, kind sucks I just bought a new one, thankfully not really expansive. I might use Ouka for finishing and stroping now. Thank you for the insight!


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## Kawa (Apr 7, 2022)

I dont have any problem losing too much teeth when stropping on leather per se.
Finishing some random stainless on 5k+ and 0,5 micron strop? Yes. Yeah, that will be slick. Too slick. Cuts one meal and after that you really have to initiate the first cut by pushing (too) hard.

But finishing on whetever stone and removing the final burr on 1 or 2 micron (leather), makes the knife perform better.

Make sure you use some kind of strop after stone finishing. You need to remove that last remnants of burr somehow. I feel like how good i deburr, after a strop the edge is always cleaner. So if that new leather one is your only one? I would use it.

Use the Ouka (I notice you have one?) and do the paper towel test. Then just do 3-4 passes per side on the leather (or other strop). Test again. Is it better? You removed burr. Is it worse? You might have rounded the edge too much or made it too slick.
Dont do 20 passes per side like you see some bushcraft-billy do on youtube.

This way you can 'measure' what your stropping is doing for you.

For me, the sweetspot seems to be 5-6 passes per side. After that, I loose too much teeth. Before that, the knife sometimes staggers/hesitate on paper towel or rips smoking paper (then rice paper). (deburring on stone is the hardest part for me. I can improve a lot here. Still, im getting better and doing an OK job lately.)


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## blokey (Apr 7, 2022)

Kawa said:


> I dont have any problem losing too much teeth when stropping on leather per se.
> Finishing some random stainless on 5k+ and 0,5 micron strop? Yes. Yeah, that will be slick. Too slick. Cuts one meal and after that you really have to initiate the first cut by pushing (too) hard.
> 
> But finishing on whetever stone and removing the final burr on 1 or 2 micron (leather), makes the knife perform better.
> ...


Thank you, will do.


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## bahamaroot (Apr 7, 2022)

I don't use compounds on my strops under 3u. This 1u, .5u and finer stuff some push makes for too slick an edge. 3u and up will leave you some teeth. If you are using a low micron spray or paste you may as well be using an 8k+ finishing stone.


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## branwell (Apr 7, 2022)

bahamaroot said:


> I don't use compounds on my strops under 3u. This 1u, .5u and finer stuff some push makes for to slick and edge. 3u and up will leave you some teeth. If you are using a low micron spray or paste you may as well be using an 8k+ finishing stone.


Am definitely a big fan of 3 micron. Keens up most edges from 1K to 6K without killing the bite


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## Jurrian (Apr 7, 2022)

Barmoley said:


> Try the following, sounds like you might be creating a wire edge. Kippington Deburring Video


Yes, wire edge would be my guess too. I use cork to take of the wire edge, then finish with some edge trailing strokes before moving up the progression.
the book in the link is good reading for the understanding of the wire edge and how to get rid of it. Cork imo work just as good as felt, just don’t drag trough the crud you’ve created.
And ofcorse the video of Murray carter is recommended.





Knife Deburring 6th edition: Science behind the lasting razor edge (English Edition) eBook : Kraichuk, Vadim: Amazon.nl: Kindle Store


Knife Deburring 6th edition: Science behind the lasting razor edge (English Edition) eBook : Kraichuk, Vadim: Amazon.nl: Kindle Store



www.amazon.nl


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## Benuser (Apr 7, 2022)

As far as I have seen, it is impossible to fully deburr with edge trailing only. The edge trailing tends at least to flip the burr, which is fine, if the burr get reduced. Often though, the old burr gets abraded and a new one formed. You may verify with a truly burr-free edge. Perform a very light edge trailing stroke, and a new burr will appear. Edge trailing should at least be completed with longitudinal strokes. Less waste of material occurs with edge leading strokes. Stropping the opposite side on your hand will push all debris to the side where you're going to deburr.
By the way, if it is a real wire edge, a burr on top of the apex, it's very hard to get rid of it without damaging the edge behind it. Often caused by too heavy, edge trailing alternating strokes, or use of a jig. Debris from both sides get on top of the edge. Better start again the entire sharpening, and change the technique. Consider working on one bevel before changing sides.


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## psfred (Apr 9, 2022)

I agree, if you are getting very noticeable loss of sharpness quickly, you probably have a residual burr that is failing or folding over, leaving the knife edge quite dull. If you don't have one, a 20x loupe will help you out a lot with sharpening, especially looking at finished edges for signs of burrs.

However, cutting vegetables with hard skins and soft insides like tomatoes does not require a razor edge, and in fact a razor edge will not cut them without push cutting after a few tomatoes, you need some saw tooth character on the knife edge to cut the very thin but very hard skin. Ditto for peppers. 1K edge followed by light polishing on a 6k stropped on denim to ensure the burr is gone is what I would do. I'm not a professional, but I sharpen all my kitchen knives this way and they stay sharp for months.

My VG-10 knives will be "magically" sharp for a meal or two, then become just very sharp and easy to use for many, many more uses before I feel the need to sharpen again. 52100 can be honed up to a razor edge, but I find I don't really need that, a slightly "toothy" edge works much better for onions, tomatoes, and beef or pork. Save the super edges for fish, where you don't have the connective tissues to deal with like you do in beef or pork or chicken.


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## KingShapton (Apr 9, 2022)

I'm a little late to the party - but still my 2 cents:

Deburring edge leading only, always leading!

And control your pressure, pressure-management is an important key! The suggested guide by Peter Nowlan is an excellent help.

Some members here have already mentioned it - razor-blades-same-sharpness is not always (actually never apart from a few special jobs) ideal for kitchen knives. Realize you're cutting food, not hair.

Different stones and different grit ranges produce different levels or different kinds of sharpness. Some create a lot of bite, others less and the respective user always has to find the optimal finish for himself.

Here in the Sharpening Station you will find pages and pages of threads on the subject of edges with bite. For example, @branwell has excellent tutorials on hybrid-edges - an edge with bite doesn't have to be coarse. Others swear by natural stones etc...

My advice would be: work on your deburring technique and only use edge-leading. Also work on your pressure management. And read up on the topic of which finish for which purpose.

I've tried everything myself - super high and fine finish, tons of natural stones, hybrid edges, coarse edges and it took me a long time to find what worked for me. But it was worth it!


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## ModRQC (Apr 9, 2022)

At one point I loved sharpening so much and spent so much time at it that my problem was rather edges not dulling fast enough… 

Just sayin…


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## M1k3 (Apr 9, 2022)

ModRQC said:


> At one point I loved sharpening so much and spent so much time at it that my problem was rather edges not dulling fast enough…
> 
> Just sayin…


Glass or marble cutting board. You're welcome.


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## ModRQC (Apr 9, 2022)

Try a couple swipes on the side of a coarse stone. Faster and more controlled dulling.


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## blokey (Apr 9, 2022)

Thank you guys! I’ve been trying the advice in this thread and they worked well for me so far, toothy edge really helps.


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## blokey (Apr 9, 2022)

KingShapton said:


> Realize you're cutting food, not hair.


But I am addicted to shaving my arm hair with kitchen knives...


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## ModRQC (Apr 9, 2022)

blokey said:


> Thank you guys! I’ve been trying the advice in this thread and they worked well for me so far, toothy edge really helps.



BTW you can use the 5K still for fine deburring and perhaps even adding a bit of refinement on that 1K bite. Experiment with it if you wish too.


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## hendrix (Apr 9, 2022)

+1
I thought that was just me. Glad I’m not alone 



ModRQC said:


> At one point I loved sharpening so much and spent so much time at it that my problem was rather edges not dulling fast enough…
> 
> Just sayin…


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## ModRQC (Apr 9, 2022)

hendrix said:


> +1
> I thought that was just me. Glad I’m not alone



If you haven't already, wait 'til you're really started into thinning...


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## M1k3 (Apr 9, 2022)

ModRQC said:


> If you haven't already, wait 'til you're really started into thinning...


If you're really looking for some fun, start sharpening for the local restaurants. All kinds of knife conditions going on. Can opening. Screwdriver usage. Smashing lemongrass. Scraping old grease. Pry bar. Sometimes cutting stuff even!


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## ModRQC (Apr 9, 2022)

Hey man I reacted all along your plea... but from a guy pretty incisive towards working companions (would it be sharpening the mandoline without their knowing or "putting their gear" into some Godforsaken place in a pro kitchen) I think you were just charmed by said lady.

I won't say ANYTHING ELSE if you agree.


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## KingShapton (Apr 10, 2022)

blokey said:


> But I am addicted to shaving my arm hair with kitchen knives...


I totally get it! It works even after 400#...but I wouldn't try it on my face...


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## blokey (Apr 10, 2022)

KingShapton said:


> I totally get it! It works even after 400#...but I wouldn't try it on my face...


Like this?


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## blokey (Apr 13, 2022)

I started to think this might more of a too fine of a edge problem now, I am using my new Fujiyama with factory edge, never touched up and not even stroped by me, it cuts everything absolutely excellent, but also skipped on a pretty tough skinned tomato. The factory edge might also been finished on a high grit stone and lack the bite.


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## Delat (Apr 13, 2022)

Time for an A/B test? Keep one knife as sharp as usual, sharpen another one at a lower grit.


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## Benuser (Apr 15, 2022)

blokey said:


> I started to think this might more of a too fine of a edge problem now, I am using my new Fujiyama with factory edge, never touched up and not even stroped by me, it cuts everything absolutely excellent, but also skipped on a pretty tough skinned tomato. The factory edge might also been finished on a high grit stone and lack the bite.


A factory edge isn't necessarily meant to be actually used as such. Often, it is only a service to the end user to allow him to put his own edge on it with only a few strokes. Traditionally, Japanese came unsharpened out of the box. The end-user, or at his costs, the retailer, was supposed to sharpen it. This has changed since knives are being exported to the entire world where home sharpening is far less common than among Japanese customers. If you get a new knife with an inclusive angle of 12° you can be sure it won't hold in Western cuisine with a lot of board contact. You probably will need the double of it, say 10° on the dominant side and 15° on the other one. A bit higher with very thin blades like lasers, when there's little steel to support the edge. Performance won't suffer if you keep the blade reasonably thin enough behind the edge. Edge retention though will increase dramatically.
As for the wire edge, it is common amongst jig users, and others who insist on keeping the same angle through the entire progression. This is of course good practice, but you may want to verify whether you really reach the very edge on every stone in the progression. If you use a permanent marker and a loupe you may be surprised that this isn't always the case, even if a burr has appeared on the opposite side. Not reaching the apex results in collecting debris on top of the former edge and, voilà, a wire edge. Very sharp until the first board contact, leaving a moonscape-like edge behind.


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## blokey (Apr 15, 2022)

Benuser said:


> A factory edge isn't necessarily meant to be actually used as such. Often, it is only a service to the end user to allow him to put his own edge on it with only a few strokes. Traditionally, Japanese came unsharpened out of the box. The end-user, or at his costs, the retailer, was supposed to sharpen it. This has changed since knives are being exported to the entire world where home sharpening is far less common than among Japanese customers. If you get a new knife with an inclusive angle of 12° you can be sure it won't hold in Western cuisine with a lot of board contact. You probably will need the double of it, say 10° on the dominant side and 15° on the other one. A bit higher with very thin blades like lasers, when there's little steel to support the edge. Performance won't suffer if you keep the blade reasonably thin enough behind the edge. Edge retention though will increase dramatically.
> As for the wire edge, it is common amongst jig users, and others who insist on keeping the same angle through the entire progression. This is of course good practice, but you may want to verify whether you really reach the very edge on every stone in the progression. If you use a permanent marker and a loupe you may be surprised that this isn't always the case, even if a burr has appeared on the opposite side. Not reaching the apex results in collecting debris on top of the former edge and, voilà, a wire edge. Very sharp until the first board contact, leaving a moonscape-like edge behind.


Thank you for the thoughtful insight, Fujiyama does come pretty sharp, it might more have to do with the low inclusive angle you mentioned, I will try to add my own while sharpening.


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