Testing Sharpness

[Ted S]

I know there are scientific ways to test sharpness but it seems that most videos show a sharp knife slicing a piece of 8 1/2 x 11 computer printer paper. If a knife easily slices thru a piece of computer paper is that considered a Wicked Edge?

I have never seen any video where the person was cutting a single page from a telphone book.

After sharpening a Hen & Rooster steak knife at 20 degrees on a WEPS (100/200/400/600/800/1000) the knife easily sliced thru any side of computer printer paper.

It did not slice thru all sides of a telephone book page.

Telephone book page – top of page, right side of page, bottom of page and left side of page that was torn from the phone book. Knife easily sliced thru right side of page. It did not slice thru the top of page or bottom of page. It was hit or miss slicing thru the torn left side.

Why wouldn’t the knife slice thru the top of the page or botom of the page?

[Mikedoh]

There are some YouTube videos by jdavis882 and smokeater908 that show phone book and even tissue slicing. I haven’t done much paper slicing myself, but I think how it’s being held might make a difference. HTH

[Ted S]

I agree that the way its held makes a big difference. In my case, I held the knife and the phone book page side the same way.

I wonder if you need a very high quality knife that creates a super edge to slice thru tissue paper?

Edit: Just watched smokeeater908 “cut test” video where he alternates between cutting cardboard and phone book pages (any side). His knives easily cut thru phone book pages even after 80 cardboard cuts.

So the question is – Did I do a bad WEPS sharpening on Hen & Rooster knife or is it as sharp as it can ever be using stones 100 to 1K?

Can a $10 knife be sharpened to the same level of sharpness as a $200 knife? I know the $200 will retain its edge longer.

[cbwx34]

Most paper has a grain… so it will cut easier in one direction than the other.

I personally have found that, as my sharpening experience increased, the level of sharpness went up. There are a lot of subtle factors in sharpening you’ll discover, everything from how you hold the stone, how much pressure you use, the direction/pattern you move the stone, etc. all can effect the level of sharpness.

Do you have any strops? Light stropping can clean up an edge and noticeably increase the level of sharpness.

Also, as your stones break in more, you’ll get a more refined edge.

(Just throwing a few thoughts out there).

[Josh]

I test sharpness in a few different ways… Slicing paper (for kitchen knives), shaving just a bit of arm hair (all knives), and actually cutting rope (for edc’s to check for bite). Slicing paper does have to do with how you hold each. Cutting directly down perpendicular to the edge is harder to do then slicing at an angle…

[Ted S]

Most paper has a grain… so it will cut easier in one direction than the other.

I personally have found that, as my sharpening experience increased, the level of sharpness went up. There are a lot of subtle factors in sharpening you’ll discover, everything from how you hold the stone, how much pressure you use, the direction/pattern you move the stone, etc. all can effect the level of sharpness.

Do you have any strops? Light stropping can clean up an edge and noticeably increase the level of sharpness.

Also, as your stones break in more, you’ll get a more refined edge.

(Just throwing a few thoughts out there).

Thanks for the feedback. I don’t have strops yet.

So it seems that the cheaper Rooster and Hen knife is not as sharp as it could be. True?

How much pressure do you use? What direction/pattern?

[cbwx34]

(Boy, I hope you’ve seen the movie.) 🙂

I’m always hesitant to answer questions on knives I haven’t specifically sharpened, but I think it’ll get a little sharper.

Light pressure usually results in a better edge, especially on the finer stones. Changing direction will change how the knife will cut, because it changes the direction of the striations. Best way to answer is, now that you’re aware of other factors (thus the video), you can play around and find what works for you.

If you dont have strops, you can improvise… one that will clean up an edge a bit without killing it if you do it wrong, is to put some newspaper on a flat surface and strop on that… alternating sides.

[Ted S]

I test sharpness in a few different ways… Slicing paper (for kitchen knives), shaving just a bit of arm hair (all knives), and actually cutting rope (for edc’s to check for bite). Slicing paper does have to do with how you hold each. Cutting directly down perpendicular to the edge is harder to do then slicing at an angle…

If you sharpened a knife at 20 degrees per side up to 1K diamond, would you be able to easily slice thru
the top or bottom (at an angle) of a telephone book page?

As I mentioned earlier, the cheap knives I sharpened to 20 degrees can easily slice thru the long side of a telephone book page but not the short sides (top and bottom).

I always slice at an angle.

I went back and reviewed smokeeater vids and it seems he always slices thru the long edge of a page and never cuts thru the short end (top or bottom of page). He also seems to sharpen at a 15/30 degrees.

[wickededge]

I went back and reviewed smokeeater vids and it seems he always slices thru the long edge of a page and never cuts thru the short end (top or bottom of page). He also seems to sharpen at a 15/30 degrees.

I think Curtis is right – the paper has a grain and is easy or difficult to cut depending on the direction of the cut.

-Clay

[Ted S]

I went back and reviewed smokeeater vids and it seems he always slices thru the long edge of a page and never cuts thru the short end (top or bottom of page). He also seems to sharpen at a 15/30 degrees.

I think Curtis is right – the paper has a grain and is easy or difficult to cut depending on the direction of the cut.[/quote]I realize that because of the grain, it will be easy to cut with the grain and more difficult against the grain.

If you or anyone else sharpened a cheap knife at 20/40 degrees up to 1K diamonds, would the knife be able to easily slice thru the short side of a phone book page?

I am just trying to determine if I am getting the best results from the WE. I have tried hundreds of strokes per side for each grit as well as varying strokes (circular, scrub and sweep) and I have never been able to easily slice thru the short sides (top or bottom) of a phone book page.

[Josh]

I tried both newspaper and phone book paper both directions (top to bottom and side to side). I found that it does seem there is some truth to the paper grain… I was able to push cut S curves long direction (top to bottom) but had trouble when doing this from side to side on the phone book paper… the only trouble was when I tried to bring the cut back towards the side of the paper that I was holding it on… hope that makes sense.

[cbwx34]

If you or anyone else sharpened a cheap knife at 20/40 degrees up to 1K diamonds, would the knife be able to easily slice thru the short side of a phone book page?

I am just trying to determine if I am getting the best results from the WE. I have tried hundreds of strokes per side for each grit as well as varying strokes (circular, scrub and sweep) and I have never been able to easily slice thru the short sides (top or bottom) of a phone book page.

Hi Ted:

I tried a quick test this morning to answer your question. I took a cheap “Made in China” “Surgical Stainless Steel” (which I’ve heard is often 440A or less), and sharpened it at 20 deg., stopping at the 1000g diamonds. I was able slice all four sides of a phone book page, both straight in and at an angle as well as pushcut, although on the short side it started to tear after a short distance.

A lot is mentioned about stone break-in, but another factor to consider is pressure. I know when I first got the WE, I used way too much, and it affected my results. I actually took a break from it for a while, and when I came back, I noticed I was using less pressure, my strokes seemed smoother, and the results were noticeably better.

I also finish my knives by doing edge trailing strokes from the tip to the heel. This sets up the “teeth” in a direction that facilitates slicing. Not totally necessary, but if you try both ways, you should see a difference. An alternative would be straight up and down, but I like the first way better.

Hopefully that helps a bit.

[Gary Crumb]

Yes, pressure makes alot of difference! My sharpest sessions have always been when I am being “delicate” with the paddles, especially on the higher grits. I find trying to slow down and be more deliberate helps lighten the touch, too. When I am in a hurry, I find myself getting a little ham-fisted on the paddles.

When I am stropping, I set the wicked edge in my lap so I am more “over” the blade. I find it helps me, but of course, we are all different. Plus, my base is round. I used some drops from cutting mdf rings for my speaker box. Waste not, want not. 😀

Testing I do on those shiny catalogs they send you in the mail. Thin and slick, nice test for a razor edge but for tooth, some rope or cord.

[Ted S]

I also finish my knives by doing edge trailing strokes from the tip to the heel. This sets up the “teeth” in a direction that facilitates slicing. Not totally necessary, but if you try both ways, you should see a difference. An alternative would be straight up and down, but I like the first way better.

Thanks Curtis. Finishing with tip to heel trailing strokes made the difference. I can now easily slice thru any side (top, bottom, left or right) of a phone book page.

[Author]

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