How Sharp with WE 1000

[Bill Sutherland]

Should the blade be hair shaving sharp after progressing from 100 through 1,000? Does the sharpness increase by going up in grit?

[Tom Whittington]

Sharpness has a lot of variables, and it’s not quite as straightforward as saying finer grits make things “more sharp” per se. That’s a discussion a lot of folks have had here on the forums and there’s a lot of great info on it and the science behind what makes a knife truly sharp!

What higher levels of polish do (independent of angle, type of steel, and so on) is refine the edge to be a smoother, less toothy cut. The type of cutting and edge finish you need really depends on the use of the knife, which is why we have techniques like micro-bevels that let you get the super polished look but retain a lower grit toothy edge for cutting utility. Best of both worlds!

To more directly address your question, the 1000 grit stones for the WEPS will absolutely get your knife shaving sharp, particularly once it’s worn in a bit and gets a little more refined. I use the 1000 stone as my gold standard with a few strokes on the 5 and 3.5um strops just to clean up and give that extra razor edge. Some folks keep just the plain 1000 grit for the bit of extra tooth and don’t strop it, and that works great too.

tl;dr yes if everything went well, and not exactly 🙂

[Bill Sutherland]

The blade is sharp but not hair shaving sharp. I don’t feel any burr so I’m at a loss as to what/where to go next. If I go up in grits it seems like a waste of time if its not going to get any sharper???

[cbwx34]

tl;dr yes if everything went well, and not exactly 🙂

So, for those who think Tom stroked out at the end, this actually means something. 🙂 (I had to google it, never seen it before).

So here was my experiment of the day. (These questions always inspire me to try something different.) I decided to see, from 100g up, at what point I could shave (arm is what I’m assuming here?). I used a small Henckel kitchen knife for this. I didn’t spend any extra time than I normally would at each level, other than finishing with a couple of very light strokes… no other refinement. Sharpening was at 20 deg. per side (40 deg. inclusive).

At 100g, I could slice thru a piece of copy paper and phonebook paper (although it would occasionally catch, especially on a slow slice). Couldn’t shave.

At 200g cleaner slices in any direction thru both papers. I couldn’t really shave, although at the end of the stroke there would be a couple of cut hairs on the blade.

At 400g, I could slice the papers, could push cut the copy paper in either direction, and phone book paper in one direction (with the grain I’m assuming). (This was the first level I thought about push cutting.) And I could shave a clean patch of hair from my arm.

At 600g (where I stopped), all of the above, and push cut phonebook paper in either direction. Still shaves… much easier.

I will say I don’t understand the statement that higher levels only “refine the edge to be a smoother, less toothy cut”, which is part of the reason I tried this, in addition to the “at what level can I shave” question. Higher refinement will also make it sharper. My experience anyway. (This could just need clarification). Verhoeven’s paper seems to support this, if you believe that a smaller width edge = a sharper edge, which occurs at finer grit levels. I think part of the issue, (probably a separate discussion) is what stropping does to an edge, especially leather, which can take the “bite” out, and/or round the edge, if not done properly.

Of course, this is one test on one style knife, but I think it’s something I’ll play around with a bit more, to see what develops, and would like others to do also. (I usually just test blades at the very end.) And, of course there’s variations, such as, what would a 100g edge that’s then stropped with leather do?

It might help to post what knife/angle/steel/etc. you’re sharpening, and the results you are getting at the 1000g level?

There’s a lot of factors, but beyond the standards points (making sure you reach the edge, no burr, etc.), I think light pressure is one that really helps.

[Bill Sutherland]

One question i have is are you stroking away or into the blade? I read where that can make a difference but don’t know when to do what.

[cbwx34]

All of the above was done edge trailing (away from the edge). I do alternate starting from heel to tip to refine the edge from the previous grit, then I switch tip to heel to set the “teeth” for better slicing, but it was all edge trailing.

Edge trailing and edge leading can make a difference though… try both and see what works best for you.

[Tom Whittington]

Mostly what I was getting at was that the definition of “sharp” is kind of nebulous to begin with, and the biggest thing you’re likely to notice with finer grits is the toothy vs. smoother cutting. Angle might make a much more pronounced difference in what would be considered “sharp”, like an exacto knife or razor blade being a very acute angle typically.

Curtis, you got me thinking when you say “a smaller width edge”… with the WEPS we’re almost taking identical amounts of material off with each pass per side, so is the edge really getting smaller? With the angles set and everything working as intended I’m inclined to think it wouldn’t, while the very edge of the edge is being refined with fewer “teeth”. Perhaps it’s more that the very apex of the edge is getting finer and smaller though the rest of the bevel isn’t (angles remaining consistent). Hooray thought experiments!

Good info on the grits and results, I’ve always considered the 1000 grit to be a really great all around finish but have done some stopping at 600 with good results also. I think Clay has some strop images under the microscope showing the “smearing” effect the strops have on a rough grit, I forget which he used though. Very cool stuff.

And yes for those unfamiliar, the acronym “tl;dr” stands for “too long; didn’t read”. It’s a light hearted way of summarizing a long post by joking it’s too long to comb through 🙂

[cbwx34]

Mostly what I was getting at was that the definition of “sharp” is kind of nebulous to begin with, and the biggest thing you’re likely to notice with finer grits is the toothy vs. smoother cutting. Angle might make a much more pronounced difference in what would be considered “sharp”, like an exacto knife or razor blade being a very acute angle typically.

Yea, I agree we’d first have to define “sharp”, although in this context at least, it’s a shaving edge. I guess my perception is different… I see an increase in sharpness at finer grit levels more so than just a smoother cut. Again, though, this may just be a difference in perspective… and pinning down the definitions. Angle definitely plays an important role too.

Curtis, you got me thinking when you say “a smaller width edge”… with the WEPS we’re almost taking identical amounts of material off with each pass per side, so is the edge really getting smaller? With the angles set and everything working as intended I’m inclined to think it wouldn’t, while the very edge of the edge is being refined with fewer “teeth”. Perhaps it’s more that the very apex of the edge is getting finer and smaller though the rest of the bevel isn’t (angles remaining consistent). Hooray thought experiments!

Yea, the part in bold is what I’m referring to, looking straight down on the edge. You can see this in the paper I referenced, and I see it looking down on edges with the little hand held microscope… the edge (looking down on it) gets smaller the higher the abrasive. Maybe one reason why pressure is important too, with lighter pressure, you can refine this, especially at coarser levels?

[Allgonquin]

Bill,

At 1000 grit on the WEPS you should definitely be able to shave hair on your arm or the back of your hand (have not tried my face!). As others have said many times, the key is to start out with the burr. If you start with 100 grit, you must raise a burr for the entire length of the edge, and you must get it from both sides. Some blades are more difficult and funkier than others to get the burr all the way along the edge, but it is key. Once you get that burr both ways, then the rest of the progression can go fairly fast, and you don’t really have to check for a burr at ever succeeding grit, since you know you are working up to the very edge after having raised the burr earlier.

By the time you get to 600 you should have a pretty sharp edge, and when you get to 1000 you will certainly be hair shaving sharp. Remember also as many others have said, your stones need to break in. They should be in the zone, so to speak after 6 or 8 knives, and get better as they wear in further.

The sharpie is key to setting angles, assuming you want to approximately match the original angle. I mark both sides, guess the angle and use 800 or 1000 with very gentle strokes to see how the sharpie mark is worn off. Adjust the angle to get the best match, then go back to coarse grits and raise the burr.

I was disappointed at first, but my stones weren’t worn in, and I did not have the burr all the way on both sides. You will get there, now I can really dial it in and sharpen almost anything!

[Jende Industries]

Curtis and I have disagreed on this before (in a constructive manner) 🙂

As per the Verhoeven, I think there are flaws in the results because of control issues with the wheels that were not addressed. There was no indication that the wheels were cleaned (calibrated), and therefore doesn’t account for variation – primarily the effects that a loaded, slightly rubbery vitrified wheel will have over time on the resulting edge vs. a freshly cleaned/dressed wheel… Verhoeven suggests that the edge itself stays at the same width once sharp, but becomes smoother through refinement.

But with that said, the info there is a great start. 🙂

My opinion on this is that “sharp” is defined when two planes meet at a 0 width – this can be at 50 grit or 5,000 grit.

Refined is another issue – and here’s were Curtis and I differ – I am of the mind that once sharp, the edge of the edge is still rather “thick”, and through refinement (at the same geometry) the edge of the edge becomes ever thinner because the depth of abrasion is reduced at each level. Verhoeven’s pictures with the width of the edge itself being measured make my argument less compelling, but see my reasoning above…

To achieve “shaving sharp” is relative, too. Cutting hairs on your arm does not necessarily mean it will shave your face without ripping it off. This is where I feel that through refinement the edge of the edge becomes thin enough to sever hairs without pulling them or scraping up the skin around them.

This is where I feel that diamonds at the lower grits, especially plates, are false-positives for shaving – the depth of the scratches form micro serrations that create areas thin enough to sever hairs within a still “too thick” bevel. (We’ve seen and documented the differences in scratch depth with the stock plates and the diamond pastes) This also suggests the change of feel in the balde from a toothy saw-like edge to a smoother slicing edge.

When all is said and done, I concur that with good, light technique and on broken in plates, think the edge should be thin enough and smooth enough by the 600 diamonds to cut hairs off your arm, for whatever reason. Not to be too argumentative, but I challenge anyone to shave their face off the 600 diamond stocks, I’m pretty sure it will hurt.:P

[cbwx34]

Curtis and I have disagreed on this before (in a constructive manner) 🙂

I don’t think we disagree, as much as I don’t understand your theory. You’ve said before, and again today that an edge is “zero” at any grit level, but that it’s somehow further refined? (See below).

As per the Verhoeven, I think there are flaws in the results because of control issues with the wheels that were not addressed. There was no indication that the wheels were cleaned (calibrated), and therefore doesn’t account for variation – primarily the effects that a loaded, slightly rubbery vitrified wheel will have over time on the resulting edge vs. a freshly cleaned/dressed wheel… Verhoeven suggests that the edge itself stays at the same width once sharp, but becomes smoother through refinement.

It’s a point in several of the sections beyond the TruHone (waterstones, Tormek, etc.), so I’m not sure this applies. For example, he talks about it in the section on sharpening on “flat stones”.

But with that said, the info there is a great start. 🙂

My opinion on this is that “sharp” is defined when two planes meet at a 0 width – this can be at 50 grit or 5,000 grit.

Refined is another issue – and here’s were Curtis and I differ – I am of the mind that once sharp, the edge of the edge is still rather “thick”, and through refinement (at the same geometry) the edge of the edge becomes ever thinner because the depth of abrasion is reduced at each level. Verhoeven’s pictures with the width of the edge itself being measured make my argument less compelling, but see my reasoning above…

This I’ve never understood, so this may be a good place to explain. How can you have a 0 width edge at 50 grit, that can still be “thick” and get thinner with refinement. I agree that refinement thins the edge which makes it sharper, it’s what I said earlier, but that’s because it’s not 0 to begin with.

To achieve “shaving sharp” is relative, too. Cutting hairs on your arm does not necessarily mean it will shave your face without ripping it off. This is where I feel that through refinement the edge of the edge becomes thin enough to sever hairs without pulling them or scraping up the skin around them.

The 400g I referenced earlier is shaving, not pulling or scraping skin. Face shaving is different because facial hair is harder to cut. (For example, the razor blade company in the Modern Marvels on sharpening, equates cutting facial hair to cutting the equivalent diameter in strands of copper.)

This is where I feel that diamonds at the lower grits, especially plates, are false-positives for shaving – the depth of the scratches form micro serrations that create areas thin enough to sever hairs within a still “too thick” bevel. (We’ve seen and documented the differences in scratch depth with the stock plates and the diamond pastes) This also suggests the change of feel in the balde from a toothy saw-like edge to a smoother slicing edge.

I don’t agree here. Arm hair is easier to shave because it’s a different type of hair. The few cuts I got at 200g is probably what you’re describing… a few random hairs that showed up. But clearing an entire area of hair… I doubt is all the hairs finding a thin area in a thick bevel. If it is, then wouldn’t it mean that the majority of the “thin areas” is doing the cutiting anyway?

When all is said and done, I concur that with good, light technique and on broken in plates, think the edge should be thin enough and smooth enough by the 600 diamonds to cut hairs off your arm, for whatever reason. Not to be too argumentative, but I challenge anyone to shave their face off the 600 diamond stocks, I’m pretty sure it will hurt.:P

You’re right, it does, I tried. :ohmy: Again though, it’s because you’re cutting a different type of hair, not that one is shaving and the other is not.

[Tom Whittington]

From what I’ve gathered, I think that we’re all basically saying the same thing conceptually. The “zero” is that the angles are perfectly set, and further refinement at finer grits is microscopically thinning the very apex of the edge while simultaneously smoothing it by decreasing the size of the teeth caused by the abrasive scratches.

I think my original point was that for most practical applications, at least from my own experience since the VAST majority of sharpening I do is EDC and hunting knives rather than fine cutlery or razors, was that the smoother cutting is the primary thing I notice when increasing grits. In the bulk of my sharpening work and the types of knives I work on the sharpness (generally speaking) is already established by the 600 grit, and definitely beyond sharp by 1000 🙂 So anything past that isn’t really showing a major difference in what it can cut, just HOW it cuts, if that makes any sense.

But hey, we started a whole other interesting conversation by my generalizing! I suppose that’s a win of a sort too :silly:

[Ken Buzbee]

But hey, we started a whole other interesting conversation by my generalizing! I suppose that’s a win of a sort too :silly:

The very definition of “Optimist”! 😉

Ken

[Jende Industries]

Here’s my take 🙂

First try this experiment: Take a 600 diamond WEPS and an 800 Chosera and sharpen similar knives at the 18 degrees. Although there is a slight micron difference, both are rather coarse. You should be able to cut hairs off the 600 diamond (perhaps with a little pressure), but you’ll be harder pressed to cut hairs off the 800 Chosera.

The question is, Why?

Basically, I believe that if you have an abrasive medium, say 1K or better yet ~15 microns, the size and hardness of the abrasive will cut into the edge of the edge, theoretically making the edge 7.5 – 15 microns wide (since the particles are embedded). It’s my belief that that size abrasive will simply abrade through the entire edge otherwise. So when you get up to 10K or ~1.5 microns, the more shallow scratches simple allow the edge of the edge to be thinner, or theoretically around .75 – 1.5 microns wide before it “abrades through”.

The false-positives are an interesting phenomenon because diamonds are usually firmly embedded and really hard. They score through a thicker bevel, leaving scratches that make those points thinner at the actual edge. Hence the hair cutting ability at such low grits.

It’s the difference between the deep scoring of the diamonds and the more shallow scratching of other mediums that has led me to this way of thinking.

It could be that we are arguing the semantics of the same thing 🙂

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