# Trouble sharpening the curves of knives



## adletson (Dec 10, 2012)

I tried once again this weekend to sharpen my knives (worked on Forschner 8 in chef's as a practice and Miyabi Kaizen 8 in gyuto, which is what I use the majority of the time) and can get a serviceable edge on the flat parts. Not great, but serviceable. It bites into my thumb nail when I'm done that I can be satisfied. However, as soon as the blade curves, there is a noticeable drop in cutting performance. 

I have taken a magic marker and colored the bevel. I know I'm hitting the bevel, but it seems to be spotty that I'm hitting the whole thing with a full stroke. I have watched Jon's video on sharpening knife tips to no avail.

Basically I am trying two things. One is Jon's way, of rotating from the spine to the edge with the knife almost parallel to the stone. The other is just trying to adjust the knife to the stone where the bevel is consistently hit and I am failing in both. Help!

Oh and the stones I'm using is a Beston 1000 and Norton 4000/8000 combo.


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## Pensacola Tiger (Dec 10, 2012)

Are you using at least a 10x loupe to check if you are actually getting to the edge? Can you feel a burr on the curve?


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## adletson (Dec 10, 2012)

I have a loupe, but at the risk of sounding like an idiot, I'm not sure what I'm supposed to be looking for. I have used it and don't seem to gather any useful data.

The burr on the curve is not consistent on the whole thing, and while it does feel like something is raised, it isn't as pronounced on the straights of the knife.


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## tk59 (Dec 10, 2012)

If it looks like you are hitting the entire bevel but you are not sharpening the edge, it isn't usually a big deal. Stock bevels are not always perfect and they will change to suit your stroke over time, regardless. I would just continue a little more until you get a burr and call it good. If you clearly are not hitting the entire bevel, then you will need to adjust your angle either by raising the handle relative to the tip a bit in the curved areas or raising the spine slightly on that part of your stroke. Try watching the edge on a clean stone and make sure it hits the stone. You should also be able to hear the difference. Slow down and listen. As you go from hitting the edge to not hitting the edge, the sound will change. Adjust to keep the sound consistent.


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## Pensacola Tiger (Dec 10, 2012)

adletson said:


> I have a loupe, but at the risk of sounding like an idiot, I'm not sure what I'm supposed to be looking for. I have used it and don't seem to gather any useful data.
> 
> The burr on the curve is not consistent on the whole thing, and while it does feel like something is raised, it isn't as pronounced on the straights of the knife.



Using the loupe allows you to see that you are sharpening to the edge by letting you see that there isn't a hairline of marker left on the bevel, indicating that you haven't hit the edge. Without magnification, it's possible to miss seeing it. You should see shiny metal all the way to the edge. Tilt the knife one way and the other so that the light reflections can help you see if it is. 

That the burr isn't well-formed is also another clue that you need to do more work with your 1000 grit stone. 

When sharpening the curved part of the blade near the tip, raising the handle of the knife slightly while keeping the edge tangent to the direction of sharpening will help. This is where using the marker will help a lot in refining your technique. Make a few passes, evaluate what you've done, renew the marker and repeat. If your bevel toward the tip is wider than the bevel at the heel, you need to raise the angle that you are using to sharpen the tip. This is one of the tricky parts of freehanding, because the angle you hold the knife at is not the same for all parts of the blade. 

Rick


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## wsfarrell (Dec 10, 2012)

tk59 said:


> If you clearly are not hitting the entire bevel, then you will need to adjust your angle either by raising the handle relative to the tip a bit in the curved areas or raising the spine slightly on that part of your stroke. Try watching the edge on a clean stone and make sure it hits the stone.



Instead of raising the handle or spine, you might check out Jon Broida's tip-sharpening technique, here: https://www.youtube.com/watch?v=tmBTO0cA_qw


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## JBroida (Dec 10, 2012)

actually, i agree with tinh in this case... but i also probably need to reshoot my tip video


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## rdm_magic (Dec 10, 2012)

Keep practising - good luck!


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## Ordo (Dec 10, 2012)

To get precision tip sharpening better grab the knife from the blade using a towel or cotton cloth (so you will not cut yourself), not the handle. You'll get much better and controllable results.


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## tk59 (Dec 10, 2012)

wsfarrell said:


> Instead of raising the handle or spine, you might check out Jon Broida's tip-sharpening technique, here: https://www.youtube.com/watch?v=tmBTO0cA_qw


 Look closer. Raising the spine rather than the handle IS the tip sharpening technique Jon demonstrated in his vid. You can't change the angle you're working at without doing one or the other.


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## tk59 (Dec 10, 2012)

After looking at it again, the handles goes up at the curve, too, lol.


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## mhlee (Dec 10, 2012)

tk59 said:


> Look closer. Raising the spine rather than the handle IS the tip sharpening technique Jon demonstrated in his vid. You can't change the angle you're working at without doing one or the other.



I learned this after talking with Jon and seeing this first hand. I used to try to do full length strokes which required a lot of elbow-work by raising the handle up, which is ok for medium sized knives, but really uncomfortable for longer knives. It was also really hard to keep a consistent bevel as well using this technique for longer knives in my experience. 

Rotate the handle so that the spine points up/vertically, but not the position of the handle, as you get closer to the tip (this applies to each side). This creates a steeper angle (which compensates for the curve at the tip of the knife) and allows you to keep a consistent angle on the stone. Just keep in mind that you don't have to rotate it too much. 

FWIW, I'm still getting used to it, but I started practicing slowly, and it's really helped me from creating a bird's beak on the tip of my double-beveled curved tip knives.


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## Pabloz (Dec 10, 2012)

tk59 said:


> After looking at it again, the handles goes up at the curve, too, lol.



Tinh,
After your critique on an edge I did I went back and reread some of your postings and reviewed some of Jons and Saltys videos. Based on what I got out of it all I started working the angle of attack a little differently with some good results. I start at the heal higher off the stone giving the it a less acute secondary bevel for the chopping portion of the blade and lower it as I work to the tip making it more acute for the slicing portion of the blade. It seemed that this higher to lower secondary bevel would give each portion of the blade more of what it needs for the tasks that portion of the blade does. I hope my explanation makes sense as far as the technique goes and was also wondering if this is something you or anyone else has tried. Is it worth the extra attention or just another effort in futility? Seems like it would be applicable to the context of the OP.

PZ


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## tk59 (Dec 10, 2012)

Pabloz said:


> ...I start at the heal higher off the stone giving the it a less acute secondary bevel for the chopping portion of the blade and lower it as I work to the tip making it more acute for the slicing portion of the blade. It seemed that this higher to lower secondary bevel would give each portion of the blade more of what it needs for the tasks that portion of the blade does...


To clarify, you're referring to the bevels that make the cutting edge as "secondary." Around here, it was agreed that we would call the bevels that form the cutting edge "primary," I believe.

That said, Salty was the one that first mentioned it to me. I've since adopted that method. The only time it isn't a great idea is if you are sharpening for someone who either abuses their tips or really needs the extra edge retention. Personally, I like the extra cutting performance this method affords. Since I have the luxury of pulling out another knife, I don't sharpen all of my heels thicker but if I know I'm only going to use one gyuto, I will make sure I take one with a stronger edge at the heel.


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## Pabloz (Dec 10, 2012)

tk59 said:


> To clarify, you're referring to the bevels that make the cutting edge as "secondary." Around here, it was agreed that we would call the bevels that form the cutting edge "primary," I believe.
> 
> That said, Salty was the one that first mentioned it to me. I've since adopted that method. The only time it isn't a great idea is if you are sharpening for someone who either abuses their tips or really needs the extra edge retention. Personally, I like the extra cutting performance this method affords. Since I have the luxury of pulling out another knife, I don't sharpen all of my heels thicker but if I know I'm only going to use one gyuto, I will make sure I take one with a stronger edge at the heel.



Yes sir, I am calling the cutting edge secondary bevels....sorry, I always thought thats what they were because the get ground second and then if micro bevels were added after that they were tertiary...?????

Thank you for the clarifications...I will keep on practicing this technique. I am exceedingly thankful for folks like all y'all that pave the way for the rest of us.

PZ


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## joels747 (Dec 11, 2012)

Jon, what stone are you using in the above video?

It looks so shiny and reflective.

Thanks

Joel


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## tk59 (Dec 11, 2012)

joels747 said:


> Jon, what stone are you using in the above video?
> 
> It looks so shiny and reflective.
> 
> ...



It looks like a Gesshin 1k. It's shiny and reflective because it's wet.


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## JBroida (Dec 11, 2012)

yeah... its the 1k


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## EdipisReks (Dec 11, 2012)

tk59 said:


> It looks like a Gesshin 1k. It's shiny and reflective because it's wet.



wait, we're supposed to wet our water stones? now all the smoke and scorching i've been getting makes sense!


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## Pabloz (Dec 11, 2012)

EdipisReks said:


> wait, we're supposed to wet our water stones? now all the smoke and scorching i've been getting makes sense!



ROFLMFAO...good one....and there is a $599.00 Shapton on it's way to you to "borrow"!!!!


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## brainsausage (Dec 11, 2012)

Pabloz said:


> ROFLMFAO...good one....and there is a $599.00 Shapton on it's way to you to "borrow"!!!!



:rofl2:


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## Crothcipt (Dec 12, 2012)

Pabloz said:


> ROFLMFAO...good one....and there is a $599.00 Shapton on it's way to you to "borrow"!!!!



:Ooooh:eepwall::sh*thitsfans:


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## adletson (Dec 12, 2012)

I still haven't gotten to get back on the stones since I first posted, but hopefully I will tonight. I'm going to try the suggestions and see if I can make any improvements. Thanks for everyone's help!


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## mdoublestack (Dec 12, 2012)

Good thread guys. Thanks


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## adletson (Apr 12, 2013)

Well 4 months to the day since my last post. I took about an hour and a half last night and went through a few of my knives (8" Forschner chef's, 150 mm Fujiwara stainless petty, 4.5 Forschner parer, 8" Miyabi Kaizen chef's). I'm gradually getting better by reading through the board. Last night was best effort on the curves to date. Problems I've identified so far:
1. I get into too much of a hurry. Every time. Really put effort last night into checking for a burr after every couple strokes. I cut down the time I usually take to sharpen and got a more consistent result.
2. I'm right handed and I don't sharpen the left side of the knife (when viewing from the handle) as well. Practice makes perfect I guess. 

All that to say thanks guys! You're helping me out a bunch!


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