# Direction of sharpening pressures?



## BobinCA (Sep 20, 2017)

OK so I watch videos of Theory and Broida and I believe they apply sharpening pressure on both the forward and return stroke until the burr is formed.
Then there are other videos ie: Korin, Osaka, and others who say to apply pressure when sharpening the right side of a double bevel knife, on the push only and relax on the return and, on the left side of the blade, to apply pressure on the "pull" stroke and ease off on that return.
Then regarding the sharpeners who use the sweeping motion ie: Kramer et al. they use edge leading strokes.


PS.... Joe at Osaka sharpening school says to form burr on the right side (on the push stroke) but then to only abrade the burr formed by pulling stroke.... but not forming a burr again on that left side

Is there a right way, better way, or what???


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## JBroida (Sep 20, 2017)

I'm pretty sure that I specifically say in my videos to apply pressure on the edge trailing stroke


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## frog13 (Sep 20, 2017)

JBroida said:


> I'm pretty sure that I specifically say in my videos to apply pressure on the edge trailing stroke


Jon,
I'm sure you do because that is where I learned to do it that way ...... and it works.


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## unprofessional_chef (Sep 20, 2017)

I'm a firm believer in pressure only on edge trailing strokes. If pressure is applied in the edge leading stoke you will most likely dig into the stone and ruin your new edge. I cringe when I see people sharpening by slicing into the stone like it's a piece of cheese. :sad0: Then I see sides of the blade marred later in the video... cringe worthy


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## Keith Sinclair (Sep 21, 2017)

Edge trailing. A experienced sharpener may look like just going back & forth. Finger pad pressure is on the trailing stroke.


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## nutmeg (Sep 21, 2017)

Just perso I find that an even surface is the result of a perfect control and rhythm on the stone and in a way breaking the rhythm with two different pressures (back and FORTH) gives me less even results.


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## Mucho Bocho (Sep 21, 2017)

nutmeg said:


> Just perso I find that an even surface is the result of a perfect control and rhythm on the stone and in a way breaking the rhythm with two different pressures (back and FORTH) gives me less even results.



+1. I thought differential stroke pressure was reserved for single bevels? Jon?


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## JBroida (Sep 21, 2017)

Mucho Bocho said:


> +1. I thought differential stroke pressure was reserved for single bevels? Jon?



single bevel knives are a bit different... pressure on edge trailing on front and edge leading on back (uraoshi). The fact is that with double bevel knvies one can sharpen with pressure in both directions and get decent results, but its a lot easier to get great results when you pay attention to pressure direction.


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## Nemo (Sep 21, 2017)

JBroida said:


> The fact is that with double bevel knvies one can sharpen with pressure in both directions and get decent results, but its a lot easier to get great results when you pay attention to pressure direction.



Do you think that this is important throughout the sharpening progression or is it more important when refining the edge on your finishing stones (or somewhere in between)?


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## Mucho Bocho (Sep 22, 2017)

Jon when you get back to LA could you cover this in a video?


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## JBroida (Sep 22, 2017)

Nemo said:


> Do you think that this is important throughout the sharpening progression or is it more important when refining the edge on your finishing stones (or somewhere in between)?



most important with finishing stones, but helpful all the way though


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## JBroida (Sep 22, 2017)

Mucho Bocho said:


> Jon when you get back to LA could you cover this in a video?



can you remind me about this? I know i'm going to forget.


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## Mucho Bocho (Sep 22, 2017)

It will be on my mind until you clarify.


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## Nemo (Sep 22, 2017)

JBroida said:


> most important with finishing stones, but helpful all the way though


Thanks Jon.


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## zitangy (Sep 22, 2017)

My take...

Spine leading or Edge trailing..

assuming a righty...

a)IF you do it on both sides... the burr will curl and uncurl and eventually breaks off

b) I wld imagine if one side at least edge leading ( cutting into stone) at least on the other side, the burr wld be cut. THis i wld do for the finishing stage.

(i) IF spine leading leading on the upward stroke,, there is a propensity for the angle to be upwards. ON the downward stroke..edge leading, there is a propensity for the angle to be more acute as it moves closed to the body and thus this will minimise cutting into stone.

c) IF both sides are spine leading, i wld not know when the burr will break wch is important to me as it wld leave a false edge and thus i emply cutting strokes for burr removal and followed by spine leading strokes for finishing which calls for haf the normal pressure adn ultimately... just the weight of the knife for the last few strokes and hopefully , i wld have attained my uptimate apex.

d) Steel removal or initial stage... I do find that i tire easily if i am to use power strokes ( normal pressure ) on the up and down strokes... and depending on my tendency.... it is only 1 direction that has a force to it.

f) Edge leading strokes i believe leaves a coarses edge as when they cut into the abrasive particles... i do believe that it leaves a deeper striation as opposed edge trailing whereby it has the possibility of just lightly abrading over it..

whatever you do with the stone... all the rubbing.. thrusting or gliding over it is just to remove the right amount of steel , at the right place(s) to achieve the ultimate apex possible with the particular grit and attain a fine edge that steams you up...

so have fun and stay sharp...

rgds z


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## Keith Sinclair (Sep 22, 2017)

Many years ago I used pressure both ways. A Japan national Sushi Chef taught me to apply pressure on trailing strokes at angles close to the stone. I was using carbon Masamoto's at this time in the early 1980's. Using his technique was able to get sharp edges on my knives in short order.


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## Boynutman (Oct 4, 2017)

Thanks for this thread. I have been wondering about when to apply pressure during sharpening and somehow I completely overlooked this in Jon's videos.

In my mind I pictured that edge leading stroke pressure would result in abrasion with less burr creation (because I figured the material would move/flow away from the edge, instead of moving towards the edge) and would therefore lead to less deburring effort.
I guess in practice things sometimes work different than imagined. Can't wait to try it out!


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## Benuser (Oct 5, 2017)

Pressure on edge trailing leads with me to a more convexed bevel, pressure on edge leading to a straighter bevel. Poor technique probably, but I have the choice.


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## K813zra (Oct 5, 2017)

I think people put way too much thought into things such as but not limited to sharpening. Rub steel on rock, get a sharp edge. If that does not work then adjust how you rub the steel on the rock and try again. Be that edge leading, edge trailing or a some combination of both. Is one method superior to another, maybe so but I am in no position to judge.


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