As a woodworker, I've never been fascinated with the super steel knives. I've never understood the fascination, either. I was fascinated with the "super steels" when I first started woodworking, but it wore off with practical experience. Because....as I'm typing this you just hit the true point, how much work do I have to do sharpening a blade to get a certain amount of work out of it. I think if most users had to have a knife in a professional setting that was tough on knives, they'd focus a lot more on geometry and sharpenability and less on specification sheets. I personally like knives that are made of relatively simple steels, especially if they are wood shop knives, and I like them to be hardened in a range that they react to a bare leather strop well (steels in the mid 60s do not respond as much to a strop, but steels in the high 50s to about 60 do).
Indeed, the wood working community in general is extremely resistant to any kind of hype/over promotion because there is too large a base of practical experience. With knives it is a completely different thing, people buy lots of knives just to carry them or be cool - however in general most people buying chisels don't do so for the same purpose. If a chisel is uncomfortable in hand, if the edge chips, if it doesn't cut well, if it is hard to sharpen, etc. . It is unlikely that a cabinet maker will use it, but for knives this can often all be ignored if the knife is made by or endorsed by some kind of special ops/survival celebrity type. I have been around wood workers my entire life, my family are all carpenters (and fishermen). I have never really seen any of them show off a "cool" tool, but they are highly prise the one which actually work. You can't do a P. T. Barnum type approach to selling to that market, they will just look at you like an idjit. If you want them to buy something it has to work and be practical in doing so.
Cliff Stamp There is some hype (makers of tools have to market something), but it usually is appreciated by white collar folks just getting into the hobby. I was in the same boat, so I get it, and i understand why people are drawn to these wondersteel knives. It's nice that you're warning newbies that the super heavy quarter inch thick spine short knife made of wonder carbides that they're spending several hundred dollars on may not be much other than pocket jewelry as a practical thing. As you say, if you talk to professional woodworkers, you'll never hear any of it (unless they're trying to make an extra few bucks endorsing something).
I revisit your vids from time to time hence the time disparity between comments. I would add other metals and cost of the knife to the graph of work time vs sharpening time and watch the 440 series soar. 440A 440B 440C properly heat treated would cover choppers-survival camp knives as well as pocket knives and skinners etc.. I seriously believe that consumers are getting caught by shiny fishing lures designed to catch fishermen and not fish.
old commnet, good concept. However, 440 series are not very good for too much chromium, they form big carbides and reduces their hardenability and edge stability AND grindability, go for AEB-L, 12c27, 14c28n, 420HC, these are truly work horse steels
I never seem to get a knife to dull by slow wear. Always some sort of damage, weather it be dirt, sand, dropping it down the stairs, concrete, etc etc. I can only tell the difference in steels by how long they take to sharpen. I've never understood high carbide steels, since if something will damage a low carbide steel, it will probably damage a high carbide steel, and you can resharpen a low carbide steel in seconds.
Your explanation on the apex thickness to carbide width comparison is excellent. In my comments on the Rex 121 video, I now see why raising the angle wouldn't necessarily help with edge stability much.
Who can know if there is an HT issue, that maker specializes in the steel and has a good reputation. in Cartra tests like Larrin did recently Rex121 blows everything away, but a cartra machine is a very controlled system with constant load, very secure perpendicular cutting angles and control on a specific media. its basically doing what a slitting machine in a paper mill does to cut paper. a knife in a human hand is not so controlled and will be subject to lateral loading, stresses, twisting while cutting, and then this is dirty carpet full of who knows what that as being cut is putting high point pressure and side pressure on the apex which might just be resulting in early carbide tearout and fracturing that isn't going to happen in a controlled test. what is good for a robot to cut with may not be good for a person to cut with and get the same results. too many variables, so its just a running theory.
Correct me if I'm wrong, but in my own research, I have found that the higher carbide steels dull faster than the lower carbide to a point. Once a certain amount of cuts have been made the higher carbide steel tend to hold that level of sharpness for much longer. So shouldn't you be measuring at 100 cuts then at over 1000 cuts? How can you say O1 is better edge retention than K390 when you make over 1000 cuts with K390 and only 280 cuts with O1? I don't really understand how you are measuring everything either and one persons sharp is also very different from another persons sharp.
The sharpness is measured at many intervals in the cutting. The number of passes is the amount of passes to sharpen the knife. I measured this because of arguments made by Kyley Harris that edge retention scaled by the work to sharpen which is the graph on the right is very important to some people. The sharpness is measured by the length required to cut a specific cord under a specific load. In this comparison two types were used, a light spinning thread with a 35 gram load and a heavy jute with a 500 gram load. Yes, in general the responses of steels is not identical. In this comparison I am looking at the edge retention in total if the knives are taken to very dull states. If you compare at high sharpness then it tends to much more strongly favor high apex stability steels.
Just out of curiosity, at this point in time, with all the various tests you have done, the knowledge base you have, which steel is the best available today in your opinion? Obviously, blade shape, thickness and grind angles and heat treat are all crucial but just in general, for a pocket folder for cutting rope, a shingle or two, meat, paper, fishing line, sharpening a pencil, cutting nets, cardboard ad nauseum. Just your basic all around everyday usage. Which would you choose? Also, on Benchmade's site you can build your own griptilian and choose blade design and materials. Say we found an original sheepsfoot blade in 440C and we had 4 knives built just like it. One in 154CM, N680, D2, S30V. . .which would you choose? Same in every respect. Same blade shape and same HG hollow ground design. Same ergonomics, handle material etc. The only difference being blade material. 440C,154CM, N680, D2, S30V. . .I am curious to find out your opinion on these 2 questions. The 1st being which steel if the choice were unlimited and the second being limited to the Benchmade custom order 550HG scenario.
Based on the steel alone, N680, however it would depend on how they are hardening it, though Benchmade usually doesn't have any issues in that regard. I have steels in pretty much any level you could imagine, right up to things like 121REX and Maxamet at 68-70 HRC. For a basic working knife I tend to prefer simple steels such as O1 because when properly hardened they have a very high combination of ease of maintenance, toughness, strength and wear resistance. Typically when you jump to the higher carbide steels, while you do gain abrasive wear resistance, it comes at a loss of too many other things and edge blunting is rarely just do to slow wear so my main choice for a working blade would be simply 1095 or ideally W1 at 66/68 HRC. For stainless, AEB-l. If you want to be fancy, Super Blue, or Nitrobe 77 or other high nitrogen versions of AEB-L, but the practical gains are small for the cost.
Cliff Stamp Just ordered the custom grippy in N680 on your recommendation. I wanted to try S30V but I can always get that in an 808 loco later on. I am curious as to how well it will compare against my 7 year old 154CM reigning champion since you regard the steel so highly. Normally, I take everyone's opinion with a grain of salt, but in watching a lot of your videos lately, you seem to have no ego at stake or bias in the outcomes and call a spade a spade. So I will give the N680 a shot.
Robert Schmidt To be clear, I like that class of steel for particular reasons, just like I like Uwe Boll movies for particular reasons. Interested in your perspective in any case.
Just watching this again , 7:00. how can a 20um carbide help a 5um apex. the only way i can think to make it work is that the carbide is sitting very strongly in the steel matrix and it is sharpened so well and with such high quality diamond etc that it can clean cut the carbide leaving the carbide in the shape of the apex, without fracturing it, and then it will last as long as it doesn't wear. but this will only be good cutting soft material that wont fracture the carbide. it would be like using a ceramic grinding belt on soft pine, vs on glass.
Abrasives can cut carbides, if they don't well in slicing you can get weird increases in performance where the carbides tear out and leave an address saw-like edge.
From working in wood, I think tests like these depend on what you're slicing. If the older carpet has become abrasive because dust and silica particles are in it, the test will favor steels like S30V. If the slicing goes back to more common materials, then results will tend toward all of the steels that can hold a reasonable (lower) angle well will do similarly (the very low carbon steels are out, they're too soft and will wear quickly in most things and the edge will be deflected in addition to the wear). A large manufacturer of hand planes tested a new iron that they put out in MDF, which is OK if you're going to use hand tools to work MDF. I have done that sparingly in the past (the easiest way to flatten an out-of-shape MDF router table top is just to plane it). MDF is murder on more plain type steels, and as the test showed from lee valley, especially at the surfaces (not sure how MDF is finished, but the surfaces are harder and more abrasive). But the same thing doesn't occur on wood. I'm starting a test in wood to see how the results compare to published "torture test" results in abrasive materials. In woodworking, since we sharpen several times in a shop session (at least a serious hand tool user will, especially if working without power tools), the total sharpening effort and the quality of the blade in dulling becomes important, and most experienced workers tend toward simpler steels that leave their edges behind in uniform tiny particles rather than in chunks. I don't use knives for torture anything, and have ultimately ended up selling all of the knives that are high in carbides except one (which sharpens best with a deburring wheel and a buff - has terrible behavior on most stones and will yield bits out of its edge - SGPS is the steel). It can be sharpened on stones, but never yields a nice sharpness feel similar to the slick feeling you get off of carbon steel (which shows up as a very uniform edge under a microscope). It will get that slickness off of a hard buff, but with less control of final edge angle (which isn't acceptable once you switch over to woodworking). A friend recommended that knife as something to try, and later told me a tradesman friend told him it holds up much better than a typical pocket knife for scraping pipes clean (he must be a plumber). The only problem is that aside from needing that specific sharpening routine, I don't scrape pipes with pocket knives. I use knives sometimes to scrape wood, often to cut boxes, etc. The plainer steels properly hardened around 60 with 1% carbon or so dominate when total effort of sharpening is involved, and the ease that sharpening occurs because they have no real desire to hold their wire edge so strongly. Most specialty steels in plane irons that I've had (I chased them all) are long gone now, too - because of the marketing effort, they do sell well and you get most of your money back. The late 1800s and early 1900s stuff made with an eye toward consistency (like plane irons by ward and payne) is just dreamy for an actual work cycle. It cuts almost the same and leaves almost the same result when it's near dull as it does when it's freshly sharpened. The surface left behind is nice, and sharpening is uneventful because there are no strange failures to grind through.
This is a great point, edge retention is very specific to what and how things are cut. The edge retention on cardboard/ropes isn't likely to translate well to cutting woods.
Would a less fine edge with the higher carbide steel see any benefit. If your apex was not .3-.5 micron and closer o the 20 micron size of the carbide? Thinking carbide serrations. I know this would be far from an optimal edge, but, would it cut rope? Something that could be used in a maritime environment?
I am going to try some very coarse edges with these very high carbide steels. I had thought initially that would undo the performance because it would cause too much fracture, hence why I increased the polish when I increased the angle. The one thing to be concerned about, or at least clarify is that material loss is quite high with coarse sharpening, it is basically proportional to grit level.
How fast they dull make good sense, more material and the that long type of carpet holds very small pieces on dirt and over time it might as well be sandpaper.
Darrel Ralph used to cut sandpaper to check edge retention, or at least claimed he did. Sandpaper is a huge step up again though, depending on the grit. Just take a slice through 80 grit paper, even the cheap open coat stuff and see if an edge still shaves, or in fact has much cutting ability left at all.
I have been following this thread on your forum. I was expecting the 121-rex to stabilize with the higher angle. Your findings are very informative. One would think the larger carbide would benefit cutting material such as rope (acting like serrations), but, with carbide break out would you even get that benefit?
I expected it initially because I expected the behavior at 50X magnification where you can see the chipping be significantly affected by the angle carry over to the apex, which needs about 1000X magnification to see. However it doesn't carry over directly. I have a few ideas on why that happens but need to do more work to know if they are true.
These are very interesting thoughts and things to consider. I do in my opinion and uses really prefer 154cm steel. I wonder if it is because the edge holds good but is still easier to put back on. Anyways great vid. :-)
Very interesting results regarding the extreme-obtuse geometries. I would have expected the trend of acute apex angle degradation with HCV steels to continue as you went further and further obtuse. Interesting that it did not. I maintain my objections to Kyley's sharpening/use ratio comparison. While it is an interesting metric certainly, it fails to highlight a number of factors. You mentioned blade design, but my point would be fixed sharpening costs; for those of us who don't store most of our sharpening equipment out and ready to use and/or don't sharpen multiple knives very frequently, resharpening a knife and cleaning up afterward takes more time than simply the PPS.
I am not sure what you mean, you would have expected the HC steels to get worse relatively as the angle increased? No doubt, it is just one metric is all, it should not be used in isolation. I think it has merit and it also asks interesting questions because the same scaling would closely relate to damage/repair type scaling. However if you power sharpen, or even you only do light sharpening and you pay for periodic recutting of edges then it means nothing at all practically. If you use very high end stones and have a lot of grit/abrasives available then it doesn't mean as much either.
Cliff Stamp As apex angles become extremely steep, as you've demonstrated, steels with ultra fine grain and lower carbide volume which have high edge stability gain significant advantages in edge formation and retention over their larger carbide fraction counterparts. I'd have expected that trend to be able to be expanded across larger carbide volumes and more obtuse apex angles. (and you did as well apparently, which you noted in the video)
Whatfor5 That the performance (relative) should change - yes, I expected that. However while you see it in the edge, it doesn't seem to happen in the apex directly. I think it is just a matter of critical thickness being required for stability and that thickness isn't strongly dependent on angle.
You said you sharpened the bevel and the edge on the spyderco. The bevel from my understanding being say a flat grind like the spyderco, would go from the tang of the blade all the way down to the edge. So say this blade was stonewashed it would grind all that finish off. I have never herd of sharpening this unless on a zero grind where the whole blade is the edge. What was the reason for this and what performance difference is there? or did i misunderstand
Working the main bevel keeps the edge from thickening with repeated sharpening. It really isn't strictly necessary unless the knife is used really often and you want to keep the performance constant.
By judging ease of sharpening like that aren't you getting a result that is dependent on the cross section of the blade much more than the steel itself?
Yes, that is why all of the knives, aside from the Everyday Essentials Chef's had the near same primary grind sharpening contact area. Note the huge difference as you noted you would expect when you change the contact area as I did on the Chef's knife.
However the more interesting part comes when you have a steel like L6 compared to the Ozak EDC Also have you tried the Spyderco Nilakka on something like this? Seems like it should pretty good results
This whole saga (forum posts and videos) has been quite enlightening. Additionally, the relatively positive reception that the results with S30V was kind of interesting, although that might have been due to misinterpretation.
I pick the knives semi-randomly, the S30V Paramilitary was one of about a half dozen knives which could have been used. In retrospect it would have been interesting to see how it would have been reacted to if I had to use Kyley's Elmax blade which would have also been a maximum peak, higher than the S30V Para even.
Ha, now you can take the edge down to 10-20 micron and then not sharpen it and you now have a carbide saw. Looking forward to seeing your results from your future test.
Nice in depth video, I think you're making alot of sense, I'm just thinking though, just babbling but, the 25 microns would get "cut" by sharpening maybe ? if you see what I mean, also I'm thinking of buying one of tactical machetes and I was wondering which steel would be the best suited, I know it's a different category, but just to compare I'm thinking about the elasticity of the alloy and the "breaking point", of course those harder steel got to be harder to break (also how much it can be bent before breaking) it's a very interesting topic metal alloys !
sounds good thanks i'll have to look arround, the machete I saw was aug 6 I think and after looking into it, it's a low quality steel (not wonder the price was pretty low)
kudos for the effort. but wouldn't it be simpler if the test substrate be similar for all knives tested? a stack of A4 copy paper binded tightly, with a standardized weight/ pressure applied to knife just above where the edge meets the corner of binded stack of paper. depth ( sharpness), consistency of the depth-of-the-cuts ( edge wear-ability ) and edge geometry (dps/ type of grinds) is easily demonstrated. the only think I can think of which can't be quantified by the above test is impact deformation vis-a-vis high-carbide steels and carbon steels.
There is less variability in the paper, however there are two concerns : -I would have to buy it -It would take a massive amount Even if the paper was free it takes literally about a km of used cardboard to blunt a knife as a m of carpet. I have never done a check on new paper, unless you buy some kind of intentionally abrasive stock it would take many hours to do one run. I can do a carpet run in ~10 minutes. I can do five of them in an hour easily and produce a consistent performance with about a 10-15% spread.
thanks for the reply. I have to agree cost is a factor, but cleaning up time and transportation cost is conversely reduced and the mess is more manageable. i don't know how your garbage collection system works in canada but in my area, there is extra charges for bulky item( timber/ construction ply & 2x4s and such). maybe free publication like magazines/ trade newspapers you get at paper stands?
k wong You don't seem to understand the volume of material that needs to be cut. To generate the kind of blunting achieved in the video kilometers of cardboard would have to be cut. If it was paper it would be even more, you are talking about enough paper to fill a small room for just one run, and dozens of runs were done in the work here. If you start using random magazines then you are back to having a wildly scattered cutting media and all you have done is just substituted one which has a very low blunting rate which means you are taking much longer, hours instead of minutes which means months of cutting vs a few days and literally truck fulls of paper. You can actually buy abrasive paper which is designed for edge retention testing. However as I have noted before : -that costs money, a lot of it -it generates unnecessary waste The material I cut up is already going to be disposed of, I make use of a lot of it and the parts I don't just end up in a landfill where they would have already. If I was to buy that abrasive paper then just enough for one run like I did here would be the same cost as one of the more expensive knives used and it would have no net effect aside from a slight reduction in the random scatter. I can reduce the random scatter simply by increasing the run count.
+BOOSTEDLASER This is a hard question to answer because it is very relative. It chips very easily compared to say S7, less so than S110V. It is similar to VG-10, ATS-34, D2, etc. .
+Cliff Stamp I only asked because some "expert" on a forum told me "read thread from 2005, EVERY S30v blade chipped non stop. stuff is garbage" and so on. I wondered if it was fixed or perfected. anyway great vids you make.
There were a lot of problems early on, I still have one of the original blades which was (and still is) clearly defective. Lots of rumors on why it happened, no clear answers, lots of conjecture.
This also makes you wonder if the Cartra testing is actually Too controlled, and is not really recreating what will happen to an apex in real world "avg person" use, vs a slitting machine cutting paper all day, which is really what cartra is testing. cartra is kind of telling you which steel would work the best for a machine making newspapers etc.
I prefer carbon steel knives. As opposed to the extra hard stainless and carbon mixed knives. One reason a high carbon steel knife while not as durable in edge retention to the other "modern steels". I can always can find a piece of flint rock (in my area easy to find) or any other stone harder than my blade I can sharpen it in a survival situation. Some of these new steels are so hard only a diamond hone can sharpen them. God help u if u lose that diamond hone...lol. As far as rust resistance just have the common sense to wipe the blade dry when it gets wet and add oil or grease from animal fat to the blade to keep it lubed. Laziness is a cruel master.
Makes me re think my choices in selecting a blade steel. I remember the good ole days when I didn't know much about knives and if it cost more the steel was better. Or, uh, I'm not sure, mind is still blowing.
I know cliff has passed. I just need to mention. The way carbides are distributed in cpm steels arent the way he describes them, and they maybe will have some segregations (generally not really, but I'm just saying maybe for the sake of argument). However, these carbides are not going to be the way he describes at the edge. And the ones in s30v really arent any finer than k390 or 10v. I wont go off of memory and say 10v is actually finer... But at the very least these carbides are the same size in both steels
Cliff what are your thoughts on the tanto blade shape? Not necessarily from a tactical perspective but from a utility perspective. I noticed you have not reviewed any. I'm really attracted to the aesthetics of the design and seem to carry a few benchmade's and microtech's with tantos. I really like them even though they might not perform like a drop point or something similar.
Aichmo I have used the CS tanto. It doesn't really do what it is promoted to do, have a large increase in strength, that is simply due to the cross section. What it does is give you a secondary point which can be useful but it also removes the natural blade curvature and replaces it with straight lines which reduces some aspects of slicing/draw cutting.
I just bought a boker magnum roamer in 440 (no a,b, or c marked on blade) for $29 and a doug ritter rsk mk3 (benchmade 152) for $165 in S30V. I wanted to compare them in edc tasks... however, no matter the performance outcome, even 2 to 1 better edge retention or even 4 to 1, I would reasonably have to surmise that 5 boker's for less than the price of 1 rsk is a no brainer.
Cliff, I recently came across the very first person who is not particularly interested in knives to the level that you and I are, for example, who had managed to take notice of exactly the same thing you did when you produced a graph charting the edge retention as a function of sharpening time. This is a local guy who’s spent a fair amount of time doing deer and elk hunting, and he noted that after many years of doing it, he came to the conclusion that he is far better off when using a set of actual butchering/processing knives with what he called “soft steel” and simply carrying either a ridged steel rod or a ceramic rod with him. He noted that if he does this, he can very easily keep the edges at an optimal level of sharpness for quite a long time. As opposed to using more complex (or what he called “hard steel”) knives. I found this quite interesting, it hasn’t been particularly common for me to see guys paying much attention to stuff like this. Just thought you might like to know.
Say Heah Cliff, How wrong am I to assume that around. 1% carbon starts a decent edge retention as a rule of time, For instance 095, 1080 having less so edge retention would be lower, 1075 would have less both, etc. to 1055, Sure Temper is very important, Geometry is very important and for what your going to use the steel for, The lower carbon might be better for chopping. Ok, But with high RC and super steels, Again 1095 is usually my yardstick measure that I compare my blades to have carbon in. Am I way off base ? Thanx in advance.
Edge retention depends on many properties, I don't think simple rules will fare well. Imagine trying to get simple rules for basketball skill. Now you could try something like, well at 6'6" you start to be decent at basketball but what kind of conclusions would you make from that if you tried to compare people in basketball?
From the knives I get from "normal" people, even kitchen knives are normally so dull they will barely slice cut printer paper before someone will bring the knife to me to sharpen. At this level of sharpness do you agree that the higher carbide steels (at least K390, Rex121 I have not had the opportunity to work with) generally can make more cuts than the lower carbide steels?
I'm sorry, just getting into this knife steel thing. I don't understand any of your charts- what is TCE? on a more simpler note, is scoring higher on the chart better or lower better? Sorry again, I just don't understand
If you grind a high carbide steel with a material that is harder than the carbides with smaller grit, say a 1 micron grit diamond or ceramic stone, does the action break carbide particles out of the steel or reshape them? Also would this depend on the geometry of the grinding material's particles?
+Cliff Stamp Ah, I don't mean to bother but recently I stumbled upon a discussion from a year or two ago of your experiences with Maxamet, and a mention of Spyderco planning a mule using it. Now confirmed for an early August release, do you expect a similar issue with the larger carbides in Rex essentially inhibiting performance to be present in the Maxamet? Or does it depend entirely on Sypderco's HT and the steel's production? Could problems be mitigated by sharpening methods? Actually, do you know of a metallurgy source that covers any of this perchance? I'd rather not bombard you with questions.
It is a measure of edge retention, it is calculated by summing : -sharpness * amount of material cut which is recorded periodically. It is basically a piecewise integral. There is much more discussion of it on the forums : -www.cliffstamp.com/knives/forum/read.php?3,1664,30354#msg-30354 That is where the discussion starts. The way to understand it is simple, a higher TCE means the blade stays sharper longer.
The number of passes is the sharpening time. It is large because all of these blades are being sharpened as single bevels, aside from the Chef`s knife.
for sharpening high-carbide steels, don't you have to use diamond or similarly high-hardness(cubic boron nitride) whet stones to sharpen the blades? wouldn't those whet stones then cut the large carbide particles (your fist) to the shape of the blade's edge (palm together) so that the carbide particles would fit within the high-carbide blade's metal substrate?
The apex is set with a diamond stone, the bevels are ground with a grit so coarse it doesn't see the carbides at all. In order for the carbides to be cut the grit has to be much smaller than them otherwise it will just plough it out of the way. I have tried setting the edge with diamond abrasives as well to see if that made any difference (I have all kinds of diamond plates/pastes), it doesn't.
very interesting/ tedious/ almost-anal retentive way of sharpening your blades, but I guess you are testing them out so it's justifiable. so you are saying the blade's metal substrate can't grip/hold on to the carbides if the diamond abrasive particles are too large, causing tear-outs and chipping at the edge, while higher grits will cut and shape the carbides but takes too darn long? and that you have tried various diamond sharpening agents and they don't vary much in carbide cutting/ shaping?
k wong When an abrasive git impacts a steel it causes deformation and fracture as it cuts into the steel and carves out a track in the surface. If the abrasive grit is much larger than the carbides then the fractures it creates will be larger than them as well which means the carbides will likely be torn out rather than be cleanly cut. Coarse abrasive grits are going to be on the order of 100 microns in size, they are not going to cut the 1-10 micron carbides as the facets (flat spots) on the larger abrasive are going to be of similar size to the carbides. If the abrasive is much smaller than the carbides then it is likely they will be cut to some extent as long as there is enough of them in the surrounding steel to withstand the extreme pressures needed for them to be cut as they are extremely hard, much more so than the steels and hence they can still be torn out even if the abrasive is very small. However if you tried to sharpen an edge only with very fine grits you would need a power system to do it because the cutting speed goes down very fast as the grit gets very high. Yes I have tried various diamond abrasives, DMT, EzLap, Wicked Edge plates, Atoma, various industrial pastes, etc. .
Ah, so the edge retention with both at 45dps is till same ratio I take it? Bah sorry about that I was thinking of rewording it to say that the edge retention was quite dependent on edge angle but posted accidentally
shurdi3 I believe the critical issue is the thickness of the apex as noted in the video and that doesn't change significantly depending on th edge angle. Thus a higher carbide steel is stable with a lower sharpness not a lower edge angle.
