Magazine paper is actually good for that particular test because it is glossy and your blade has to be pretty sharp to bite in. Phone book paper is tough to cut like that as well, but not quite as tough. I like to use wax paper (the stuff they sell in the baking aisle) because it is very thin and slippery.
I find this test tougher than slicing newspaper. There is no before/after. My Henckels will not pass it.
I was really surprised when I tried the paper “chop” test. It is much easier to cut with a rapid motion than with a very slow one. I particularly like the slice on a folded piece of paper standing on edge. Cuts really cleanly with a quick chop, but probably won’t cut at all with a slow slice.
Now, whenever I see a video of someone swinging their blade at a sheet of paper, I think: Yeah, right. Show me the slow cut.
That said, I’ve never tried to cut the folded (uncreased) sheet as in Redheads’ video. Looks interesting. Gonna have to try it.
There is probably a pretty big difference in force between a chop and a slow cut.
There is probably a pretty big difference in force between a chop and a slow cut.
All you have said is true, however, this was a comparison of the sharpness between 2 knives (one high grade stainless and one high grade non-stainless). It was not meant in anyway to attempt how sharp they are (ie. can they whittle hair, etc). It does introduce a question though of how to determine “how sharp” with some amount of repeatability especially when still mounted in the WEPS. This is important because some steels and or profiles will require many more strokes to get the same level of sharpness (i.e. S110V, … ). The benefit will be minimized time and steel removal. WDYT ?
Also, I have not touched these 2 knives since yesterday and will try a few other comparison tests.
I like to push cut thin paper with the blade still mounted. It’s by no means a perfect test, but it does give me tactile feedback that can help me diagnose any trouble spots as well as provide me with a qualitative measure of how sharp the blade is. I posted in another thread about the inherent difficulties of quantifying sharpness, but I think a quantitative test is the only way your’re really going to be able to repeatably differentiate similarly refined edges on one knife against another. You could probably design a testing apparatus that would measure the force in grams to cut a membrane of cord of some kind with the knife mounted in the clamp by modifying a tree beam balance.
The bottom line for me is that a blade will either be sharp enough or not sharp enough to use it how I want to. If it feels smooth while push cutting phone book or magazine paper, I find that it will be plenty sharp for my needs so that qualitative test is sufficient. It is fun to push the limits and go after that truly effortless, smooth cutting ability (that’s why most of us are here), but if I’m honest I don’t need that level of performance from a knife. I’m not a world class chef or a surgeon or even a carpenter, I’m just a internet dweller who likes sharp things. Also, I find that the extra 10% of sharpness that takes an edge from sharp to SHARP is lost pretty quickly once you actually use the knife for more than cutting paper and hair. The good part is that every knife will eventually need to be sharpened again 
I suppose a more detailed account log (incl # strokes per grit) would help me since I am sharpening the same knives over the long term. This will help me minimize time and steel removal.
I don’t clamp a knife to sharpen with a game plan of how to sharpen it based on a past sharpening experience, or sharpening result. I might have a planned stone progression, clamping position and a bevel angle that may have worked well in the past, that I’ll intend to follow. I sharpen each knife objectively and give it the time, attention and strokes necessary to achieve the results I am satisfied with during this current sharpening session, and try to do nothing more. What worked in the past and how many strokes has no bearing on this session because too many factors have influenced the condition of the edge. Such as the length of time since the last sharpening, how much I used the knife during that period of time, how worn it feels and how severe the wear is. The amount of metal I remove now correlates to this sharpening session and what amount of sharpening it requires to achieve the final results I’m satisfied with. I may even put out a little extra effort to try to improve the edge over the last time I sharpened it.
That being said, the first time I sharpen a knife that I’m unfamiliar with, it may be hard to judge when I have achieved the best edge I can. I may have to put extra time in, to finally reach that point of sharpness that I am satisfied is my sharpest effort. I may after spending more time and effort than was necessary realize I haven’t improved the edge and should have stopped sooner.
I believe most of the metal loss or removal in the sharpening process is with the earlier coarser grits. I use visual inspection of the evenness of the scratch pattern and removal of the previous grits scratch pattern as the cue it’s time to move on. After I work up to the finer grits in the progression I believe I’m doing more finishing and refinement work and very little real metal removal. I don’t think that if I limited my strokes it would have any real bearing in the overall amount of metal removed. I have found that these are the stages where extra strokes and extra effort does have the most bearing on the final knife edge sharpness.
When I sharpen the knife for the first time even if I’m able to match the existing bevel extremely closely it still is in essence a profiling process. I am removing more metal then to even out the bevels to the exacting ability of the WEPS then I will the next time I sharpen that same knife. I find it will be generally quicker and easier each subsequent time than the time before. Unless the edge has been totally destroyed, I believe with each sharpening there still is a remaining shape and evenness of the profile from previous sharpening sessions. Usually there is a time savings and an effort savings over the last time I sharpened it. In general the desired results should be easier and quicker to achieve. Of course these are generalities I have experienced while sharpening the same knives repeatedly, usually my own, and they don’t always hold true especially when sharpening knives for others.
Hey thanks for the advice. You must type fast. I redid my 2 knife sharp test on bent shiny paper scallops more slowly and found satisfying similar results. After the test I decided to take my shun blue into my new diamond films, however, I ran into an interesting issue which jives with your scenario description.
While doing the presharpen exam under my USB scope I noticed dips in the edge near the handle which I suspect is from my wife slicing hard baby carrots. I decided to fix the profile using the 200 grit as a file across the edge causing me to start from scratch. Good bye to the history on the blade like you say.
While reprofiling and examining under the scope I realized that it is not easy to do perfectly by free hand. Without a fixture you tend to follow the dips (chips are probably easier). Is there a good technique to use ?
Also, how much time does it take you to do a knife the way you describe above ?
To whom are you asking this question? If it’s directed to me, MarcH, with no sarcasm intended, “as long as it takes”. I am never under a time schedule or time crunch when sharpening. I sometimes do it a while, get up, do something else, then come back to it. If it’s a knife I’ve done over and over, and usually too frequently, I can knock it out pretty quickly, like in 30 minutes or less, because the edge is very well established and quick and easy to touch up. Those knives usually never require a full progression. Maybe, at most, a coarser grit on some bad area then a quick pass across the whole bevel to even it out. My knives don’t get too hurt, I’m the only using them; no S.O.
Like a lot of us, I sharpen because I enjoy it. So I too, often will sharpen a knife sooner than it really needs it just because it’s fun to do. Like you Redheads, I have more knives than I need, so it’s hard to use them all enough to put enough wear on them that they really need to be sharpened. I am making an effort to spread the use out and enjoy the variety and not use my favorites so often. I am trying to avoid sharpening the high dollar, super steels, (as I like to call it) until they need it just so I really have an opportunity to sharpen a knife that needs to be sharpened. These knives came really sharp and have been surprisingly durable and I want to take my time and enjoy using them and have a worn edge that really needs a full progression so I have an opportunity to learn about the steel while I’m sharpening it, that first time.
I sometimes find when I start to sharpen a knife that I’ve done many times I may try to change up my technique, to see if I get a different result then I had in the past. Hopefully better, this time, though it’s hard to judge the difference between a sharp knife, and a sharp knife. Just what this Thread is about.
MarcH, I like your approach and pretty much do the same. The knives I sharpen the most are my 8 non-serrated steak knives since we use them on plates pretty much every day. I accept the dulling action because they are a pleasure to use. I’ve gotten pretty good with my Messermeister white hone rod to quickly straighten the edge. Every 1-2 months I like to put them in the WEPS and give them a solid touch up and I can do all 8 in about an hour if I start with the 400 grit and the alignment gauge. Its knives that show more wear that I need some advice on and I was wondering how you do the following:
For knives with damaged with dips/bends in the edge due to misuse by my family what is the best technique for reprofiling the cutting edge. I would like to keep the original profile. The best I can think of is scrapping the top edge with the diamond handle using the longest part of the handle over the entire knife edge (heel to point) for each and every stroke. This can take a while yet would avoid (I think) following the dip and bring the rest of the knife to the same “level”. WDYT ?
Redheads, I too have used a coarse grit diamond paddle longitudinally across an apex to remove damaged steel and level it out and I have also used a “metal file” to remove metal at an obtuse angle , I wrote about this twice in this Forum in a different thread. I believe it removes and wastes a lot of good usable steel especially if there are fairly deep divots or chips and you flatten the entire edge heel to tip, down to the level of the worse damage. I really believe the better option is to just remove the amount of damaged edge in a manner that freshens the steel on a majority of the knifes length. There may still be the remnants of the deepest damaged areas. Then next time around I’d do it the same way with the hope that new bad chips like this were not created. Eventually with subsequent sharpenings it will even out, or it may not. In the mean time you will be able to still use the knife and each level, (so to speak) of steel, till it’s worn away with use, not wasted and discarded with a filing. If you had removed all the bad steel down to the lowest level of the deepest damage you would have wasted the opportunity to use all the steel that wasn’t damaged.
I know where you’re at; to sharpen a knife and not do the whole edge to a new pristine apex to best of your ability, every time is counter-intuitive. It’s something I learned to accept. That knife is there for this purpose of those who use it, to use it as they want and as they do. They don’t know, and they don’t care that its chipped and rolled. They only know it’s OK to use this knife. The sacrificial knife. “Let it go my friend”. Better that one then one of your good ones.
I see several situations, one is your family will continue to use and badly damage the knife as you described and you’ll continue to sharpen it as best you can and continue to piss yourself off because they abuse that poor knife and that knife will get too narrow and thick to sharpen very soon. You’ll sharpen it as I suggested and juggle between the bad spots and saving metal. You might try to sharpen it at a wider bevel angle and maybe it’ll sustain less damage, be more durable and hold the edge longer.
You might consider widening the bevel angle on your steak knives too. Give it a try for a month or two. As often as you sharpen them, they’ll be unsharpenable in not too long.
Good Luck
Readheads: Before taking the step of flattening the edge to the full depth of the worst dent or chip, I look at the damage from the side (either perpendicular to the blade axis or perpendicular to the bevel) to judge just how much steel I’d be losing. A half-millimeter ding would mean removing 0.020" along most of the edge. Within a few years you’d notice that your knives are getting pretty narrow. With steak knives, the user won’t notice the tiny little ding in comparison to the sharpness of the remaining edge. Skip the ding, pretend it isn’t there and extend the life of your knives. Wait until you get more than one or two dings.
On the same subject, I recently sharpened my sister’s Aritsugu and noticed a pretty good ding within a half-inch of the heel. With 8-degree bevels (that’s as low as I can go) I would have had to remove a lot of steel. I decided it wasn’t worth it, just to get a pristine edge. With the ding so far back on the edge, it wasn’t likely to be a problem. Saved me a lot of time and saved the knife from unnecessary edge loss. At 16-degree included, this turned out to be easily the sharpest knife I’ve ever sharpened.
Hey Readheads, off-topic, but what angle do you use on your Kramer there? I am looking to get one, but I keep seeing differing info on the angle from the factory. Thanks!
I do a 17 dps. Alignment guide L3 (the tip is in the middle of the L3 box). Knife is low in the clamp, I call it “bottom” essentially resting on the 2 prong thing which holds the alignment guide in place. I find 17 dps plenty sharp and did not put a microbevel on it. I will see how it has held up next time it is in the WPS. I love using my 250x USB scope for that.