Push/Pull question on Sharpening

As a person new to sharpening... I am still confused on one issue......

Do you put more pressure on the push (cut) or the pull (away from blade)? Or... is it equal pressure?

What is recommended? I searched the internet and have seen people recommend both methods. What do you suggest for a beginner?

Thanks!

Equal

equal is ok, and often what i tell people to do in the beginning, but the best results will come from the following:

on double bevel knives- pressure on the edge trailing motion... on the push for the right side and pull for the left (for right handed users)

on single bevel knives- pressure on edge trailing for bevel side... pressure on edge leading for urasuki (back side)

this doesnt mean that you have to lift the knife off the stone when not applying pressure, but rather just try to relax on the non-pressure part of the stroke

Internet sharpening videos range from very good to absurd with little help for the newcomer to discern between them. The ones that JKI has done are at the very good end of the spectrum.

I started confused about one issue. Now I have several...

Good luck.

JBroida said:

equal is ok, and often what i tell people to do in the beginning, but the best results will come from the following:

on double bevel knives- pressure on the edge trailing motion... on the push for the right side and pull for the left (for right handed users)

on single bevel knives- pressure on edge trailing for bevel side... pressure on edge leading for urasuki (back side)

this doesnt mean that you have to lift the knife off the stone when not applying pressure, but rather just try to relax on the non-pressure part of the stroke

Click to expand...

Thanks Jon! I've also been wondering whether it's on the trailing or leading edge and wondering why I was stuggling to raise a burr (was putting pressure on the edge-leading stroke). Mind you, I've been practicing on rubbish SS blades on a cheap (real cheap) stone so that could be a big part of the problem too Just wanted to get my technique sorted before using my good stones on my new (first) J-knife...

pressure on the edge leading stroke is not the end of the world, and shouldnt stop you from being able to form a burr, so you may want to look elsewhere for why that wasnt happening...
really there are only a few reasons for the lack of burr formation (in order of likelihood):

-wrong angle in sharpening
-not enough time spent
-not starting at a low enough grit (see above as they are related)
-work hardened steel (not very likely at all)

There are probably some others i'm missing, but these are ones i see often

Thanks again, Jon. I'll check my angles as I suspect I'm perhaps a little low and not sharpening right to the edge.

JBroida said:

equal is ok, and often what i tell people to do in the beginning, but the best results will come from the following:

on double bevel knives- pressure on the edge trailing motion... on the push for the right side and pull for the left (for right handed users)

on single bevel knives- pressure on edge trailing for bevel side... pressure on edge leading for urasuki (back side)

this doesnt mean that you have to lift the knife off the stone when not applying pressure, but rather just try to relax on the non-pressure part of the stroke

Click to expand...

Well said.I was taught many yrs. ago fingerpad pressure on trailing stroke.Before that I had tried diff. tech. sharpening fr. cooks.Most equal pressure.Everything I learned fr. a Sushi Chef including trailing press. after had the sharpest Gyuto's in the Hotel.

As John said finger pressure is relaxed on push & applied on trailing wt. double bevel knives,no need to lift knife off stone.

Chiharu Sugai of Korin knives suggest for beginners to lift the blade off the stone.I did not use this in teaching because I was concerned that the students might lose their steady spine height by doing so.

Now watching Korin video's on the web.Chiharu's assistant,don't remember his name lifts the knife off the stone in his 70/30 gyuto sharpening lession.A student bought a Fujiwara fkh carbon.I used his tech both thinning behind the edge & kicking in final bevel,had no problem at all keeping a steady spine.Also an even burr heel to tip.Took a little longer is all.Very sharp blade finish on Shapton pro 2K.

You can still get a sharp edge with equal pressure,but from my experience trailing edge pressure on DB knives is the best.

Thanks for all the help to my original question.

I also really appreciate the videos from Japanese Knife Imports..... Excellent!

I have my first set of water stones and will be practicing this weekend.

Will pressure with an edge trailing motion give a slightly convexed bevel, and the same with an edge leading a straighter one, perhaps?

not necessarily... wobble occurs on both push and pull

The only edge forward stroke I use is deburring backside of Japanese single bevels.When I strop on a polishing stone it is an edge trailing sweep.

Cant say i use edge leading strokes for anything.

when I want to give a knife a new basic bevel and wish to raise a good burr I use pressure on both leading and trailing edge strokes, without lifting the knife from the stone, I just go back and forth.

As soon as I have raised a burr and wish to chase/reduce it before removal I only use edge leading strokes, first two on each side, then change sides after each stroke, with less and less pressure after each one.

Works fine for me. I have just put a shaving edge on an IKEA Slitbar knife, the most difficult thing was proper burr removal without a strop. I really must get me one of those.

The definitive instructional videos for me are the ones this guy here made:

http://www.youtube.com/user/messermachen (German only, unfortunately)

His homepage is
www.messer-machen.de

Thanks so much to everyone for this post. I am new to hand sharpening on stones and I was doing the exact opposite, putting pressure on the forward stroke. Couldn't understand why I was gouging my Smith (not deluxe) 6000. Ha Ha. Doing what I learned here kicked me up a notch in both confidence and knife sharpness. It is much easier for me to keep a consistent edge with trailing pressure. I make sure that I am close to the edge at the beginning of most forward strokes while applying very little pressure and then just practice keeping this angle for the trailing stroke with pressure. Works great for me.

I was doing the exact same thing as well. I am learning a lot on this forum. Thanks to all.

Convexity comes from inconsistency in the precise angle at which the edge is being ground and all free-handers are going to have varying amounts of inconsistency. More pressure would give you more concave bevels. Less pressure would give you flatter bevels.

Jon can probably explain this but didn't kcma always use a huge amount of pressure when he sharpened and always wore out his diamond stones? Haven't heard of anyone else doing it like that

yeah... but i came to realize that he was really not the best sharpener... his knives showed problems in his sharpening over time and his pressure didnt make his sharpening faster or better

Why pressure on edge-trailing and not when leading? How does it make a difference?

I've always done the opposite! Pressure on lead, let up on the trail. I'm gonna have to adjust my technique. Good thing I brought my knife kit home last night so I could sharpen today! Can't wait to try it out.

The reason I was told (and I'm sure there is more to it) was that it's easier to be more consistent with light pressure on trailing strokes I.e there is less wobble

Trailing stroke can have diff. pressures.Thinning a dull blade more press. to raise a burr-lighter press touching up a trained knife.No press just weight of knife deburr gyuto.

When the knife never leaves the stone & pressure controled by releasing and applying finger pad pressure obviously it is not 100-0 say as a guess 85-15.

Like I said since I learned trail press. in early 80's I have used it ever since.Axes,Hatchets,Machete's,Wood chisels,japanese garden tools,Chef knives & japan SB on the bevel side.

I like this thread because it is highlighting this Japanese sharpening technique that I know works very well.:joec:

My method .. when I need to remove steel... I eally dont care whether it is cutting into stone strokes or spine leading... just as long as it removes steel where I want it..

a) wehn burrs are formed...

(i) if Spine leading strokes... I am merely unfolding the burr and I may be tricked into thinking that it is sharp but on weakened metal.

(ii) with edge leading strokes ( on both sides) I will be cutting the burr away adn force it to break as opposed to spine leading strokes , hoping for it to break off and touch up with a few light strokes to have a real pointy edge..

Sx, when I am not in form, mandatory one side must be a cutting stroke with the burr facing down.

I believe that it is for this precise reason that on a single bevel knife say right handed, on the ura side ( left side) it is recommeded to have a cutting stroke ( edge leading) and shld a burr form on the other side a cutting stroke again..

It is also for the same reason that on a steel ( 1600 grit) I only use an edge leading stroke..

ON a final note, the 3 variables on knife sharpening are a)grit ( abrasiveness) b) pressure c) angle. Play with the parameters. DId I forget anything else...? DO what works to make 2 angles meet adn how thin you want it and remove steel where you want to in a most efficeint way for you.. do what works and you should be fine...

have fun .. rgds D