# Sharpening a wide bevel knife for the first time



## dafox (Mar 28, 2020)

I sharpened my first wide bevel knife today but I didn't like how it turned out. It's a Heiji gyuto, 225 semistainless. The right side of the blade is ground with a sharp shinogi line but the left side is much flatter with a poorly defined shinogi. Its definitely a righty grind. I kept the original shinogi on the right side pretty well while sharpening but the left side is pretty wavy and rides up the blade in a few places. I usually sharpen knives with my right hand on the handle and use a different technique for the right and left side of the blade. I didnt like the scratch pattern so I sharpened using both hands, ambidextrously, flipping the knife to sharpen. The ambidextrous technique worked pretty well but sometimes the blade would stick to the stone and skip, seems like all of that flat wide bevel held at a 45 degree angle had a lot of contact area for sticking. So the blade would slip and resulted in a very uneven looking scratch pattern. 
I used a Chosera 400, 800, and 3000 and ground the wide bevels flat to the edge, a zero grind. When I tested the edge by cutting paper it grabbed in the belly area and towards the tip of the knife and I could even see some burr left over so I did some super light stropping strokes on the 3000 and then the blade was scary sharp.
Any suggestions about how to prevent the grabbing, sticking, and jumping that I experienced?
Is it common to have a wide bevel knife be asymetrically ground like this?
Any other suggestions?


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## M1k3 (Mar 28, 2020)

Work up a little slurry, and keep moist. Start on your 'less pretty results' side first. Relax. Just remove enough metal to see you hit everywhere. Let time fully flatten it. Unless you're going for aesthetics.


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## TSF415 (Mar 28, 2020)

I can relate. I started switching hands too. I just couldn’t get good results on the back side any other way


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## adam92 (Mar 31, 2020)

Me too, i start switch hand also, i found out easier to sharpen double bevel if switch hand.


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## panda (Mar 31, 2020)

i have the same knife, yes it's intentionally asymmetric. i suggest you cut a microbevel on the right side, this will eliminate the catching. it wont be scary sharp any more but it will be INFINITELY more durable.


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## zizirex (Apr 1, 2020)

I just follow how Mutsumi Hinoura sharpens his knife and how he put Koba.


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## kayman67 (Apr 1, 2020)

This is how I advise sometimes as I've seen in practice that for some people it's kinda natural that way since it works much faster than anything else.


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## Forty Ounce (Apr 1, 2020)

zizirex said:


> I just follow how Mutsumi Hinoura sharpens his knife and how he put Koba.



I fully endorse this video.. great example of hamaguri sharpening


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## MartinJ (Apr 2, 2020)

Hey. Considering myself as a good sharpener but not good polisher. 

I'm still not happy with my results but I found that the key to progression is almost only practicing at some point. 

I'm getting very different results by playing with pressure, quantity of water, mud etc. 

I'm just trying stuff on a higo no kami, some san mai blades, focusing and see what happens. 

Also for the moment I have some days "off" where I just cannot get good results


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## Rotem Shoshani (Apr 27, 2020)

zizirex said:


> I just follow how Mutsumi Hinoura sharpens his knife and how he put Koba.




I was going through the whole thing, can you explain a little on what he's doing?

So his progression will be coarse, medium, fine, and all throughout, he'll raise a burr laying the bevel flat on the stone and then flips it over and on to the next stone?
Then he'll cut a micro bevel with a few strokes on the last stone. 
Have I got it correctly? Is this Hamaguri or zero bevel? Having a hard time differentiating between the two.


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## Nemo (Apr 27, 2020)

I use a hamaguri technique in convex (not flat or concave) ground wide bevels.

I start by removing metal at the shinogi line (press over the shinogi line). Then remove metal at the edge (press just behind the edge) untill you get a burr. This creates a zero grind. Then blend the bevel by "wobbling" between those two angles while you sharpen. Repeat for each stone. You can use the resultant zero-grinf edge but if you find it isn't robust enough for your use, put a microbevel on it.

I found the JKI videos on this technique very helpful (thanks yet again @JBroida).


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## Rotem Shoshani (Apr 27, 2020)

So I will progress through my stones starting flat at the shinogi then raise a burr by raising the angle? Then kinda smoothly blend the 2 by going between those angles? or using both angles?

Sorry for sounding dumb, wobbling has been a big no no for me up until now. I really wanted to experiment as now I'd just thin when I need and sharpen afterwards, while this, this sounds rather interesting.
So the resultant edge would be no different than a zero grind edge, eventually? just the convexity behind is a little rounder (as a result from removing metal at 2 different angles) than what would be if you'd normally just hit the whole bevel till you reach the very edge?

Seeing the video of Hinoura San, it's really difficult to see anything besides the flat on the stone angle.

I'm going to suck at this


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## Nemo (Apr 27, 2020)

Yes you do raise the angle from the shinogi to raise a burr... but what you are really looking for is when the last 5mm or so of the blade (before the edge) is flat on the stone. You achieve this by putting pressure just behind the edge.

Remember, steel will be removed from directly under where you put pressure. Put pressure at the shinogi -> steel is remoged at the shinogi. Pressure at the edge -> steel is removed at the edge. Pressure in between -> steel is removed in between.

The wobbling is only done between the two angles and definitely not while sharpening the edge.

Did you watch the JKI videos? They made it pretty straightforward to me.


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## M1k3 (Apr 27, 2020)




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## Rotem Shoshani (Apr 27, 2020)

Nemo said:


> Yes you do raise the angle from the shinogi to raise a burr... but what you are really looking for is when the last 5mm or so of the blade (before the edge) is flat on the stone. You achieve this by putting pressure just behind the edge.
> 
> Remember, steel will be removed from directly under where you put pressure. Put pressure at the shinogi -> steel is remoged at the shinogi. Pressure at the edge -> steel is removed at the edge. Pressure in between -> steel is removed in between.
> 
> ...



So just apply this on both sides of the blade.. gotcha.

What about a faux wide bevel? Where the shinogi is just a finish representation? I'm not too sure what knives I can try this on.
I have a very beat up Tanaka VG10 that I've already thinned a bit.
Before massacre:



After massacre



Ignore the ugly flatness at the heel, will fix that too.

I also have a Yoshihiro AS petty that might fit the bill..?

New:


Post thinning and playing with finish (sorry for the poor lightning):


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## Nemo (Apr 27, 2020)

You can use this on any knife where the wide bevel is convex. For flat bevels, you just thin by grinding the whole bevel at once.

You can easily tell which is which by holding a straight edge (ruler or even a credit card) against the bevel and viewing the interface between the wide bevel and the edge. A convex bevel will only touch the straight edge at one point. A flat bevel will stay close to the straight edge throughout its width. Most flat bevels are actually very slightly concave and you may discover this when you go to thin it (you will only be able to grind near the shinogi and near the edge).

Note that you don't need to do a full hamiguriba with each sharpening, only when thinning. To refresh the edge, just touch up the microbevel.


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