Number of strokes per side in sharpening progression

[G-MAN]

Say you are sharpening a blade made of good steel (S35VN, for example) and have established the primary bevel and gotten a burr on each side.  In a general way, <u>how many edge leading strokes per side</u> does it take as you progress through the diamond stones and on through the diamond lapping films (switching to edge trailing for the films)? I realize that a good answer would be as many strokes as are required to eliminate the scratches from the previous stone.  However I’m looking for a rule of thumb.  Does the number of strokes required change as you progress from coarse stones to the lapping films. Is the number of strokes needed substantially lower for a microbevel?

[Mark76]

Hahah. This was one of the first questions I asked when I came on this forum. Of course the answer was: it depends. On the steel, on the stone, on your technique, … But if you want a rule of the thumb: 50. Then at least it’s usually not underkill.

Molecule Polishing: my blog about sharpening with the Wicked Edge

[Organic]

Based on my limited experience, I would agree with Mark76’s estimate of 50 strokes or so per side as a decent number. I don’t generally count, but that sounds reasonable. If you watch Clay’s videos, he progresses very rapidly through the grits.

1 user thanked author for this post.

Gazillion

[NotVerySharp]

Keith Parker claims 200 per side. anyone care to comment?

 

[Organic]

There’s little doubt that you will get a nicely refined scratch pattern with 200 strokes per side at each step in the progression, but I think that is quite a bit of overkill (needlessly throwing away blade steel). I can’t imagine doing 200 strokes per side with the 80 or 100 grit paddles like Keith does in his video. Those paddles eat through steel at an amazing rate.

As a side note, you will notice that the knife in Keith’s video has micro-chipping at the apex even after he finished his whole progression. I believe that the chipping arises from the jagged edge left on the apex from the 80# paddles at the beginning of the progression.

Keith Parker

My feeble attempts at embedding the video have failed.

[G-MAN]

Thanks to all for weighing in!

Is it a fair assumption that fewer strokes are needed to retouch a microbevel (since the width of the edge is much less than the primary bevel)?  Or does it take the same number of strokes, but just allows you to start higher in the progression–perhaps with the 1000 grit stone if the edge isn’t too badly damaged?

[tcmeyer]

Number of strokes is dependent on the length of the blade, the hardness of the steel, the width of the bevels, how much pressure is applied and whether or not you are a truly righteous person.   Early on, I decided that five strokes for each inch of blade length is about right and haven’t learned why that’s not a good starting point, except that it applies only to grits above 200.  To achieve a truly refined edge, stay with edge-leading strokes and increase the number of strokes with each step in the progression.  Surely, there’s a point where the number of strokes taken is shortening the life of your stones more than it’s refining the edge.  Moderation in all things.

[Mark76]

NotVerySharp wrote:

Keith Parker claims 200 per side. anyone care to comment?

I guess it depends on how really really certain you want to be you remove every scratch of the previous grit.

Molecule Polishing: my blog about sharpening with the Wicked Edge

[NotVerySharp]

TC thank you for your input.  I know none of this is written in stone but.. you say about 5 strokes per inch above 200 .  Then you say as you progress, I assume as the grit gets higher, you add more strokes? approx how many?      and aprox how much pressure do you use?  Just the weight of the stone? or do you apply a little pressure?       what about below 200 grit? more than 5 strokes per inch?               Thank you, i know it is not the same all the time, but at least it gives us beginners a general guideline

[tcmeyer]

As to pressure, since it’S so subjective, I think in terms I can relate to.  For me, I jmagine how heavy a pound of butter is when I hold it in my hand.  I also do that for a stick of butter – a quarter pound.  Using this, I’d say my normal pressure is about one pound. I’ll use more for serious reprofiling below 400 grit. For microbevels, I’m probably under 1/4 pound, but never so low as the weight of the stones.  Keep in mind that the stone is leaning against the edge, not resting on it, so only about a third of the weight of the stone is bearing against the edge.

I never do more than 5 strokes on a microbevel, usually 3.

[tcmeyer]

Added strokes??  As an example, I might do 25 @ 400, then 35 @ 600, then 40 @ 800 and 1000.  If I’m going for a mirror edge, I may do even more with the higher grits.

Different strokes for different folks.

[NotVerySharp]

TC wow, thank you.  Never realized that much pressure.  Do you have a pair of scales for food? Im surprised no one has not measured the amount of pressure by putting their fingers on a scale.  I know I’m  dummy, and subjective stuff is hard for me to deal with .  So I realize nothing is written in stone, but greatly appreciate your input TC

[Author]

Posts