I decided to try the unthinkable! I took a gd 208 that i had laying around. Dusted it off and set a bevel on my belt sander on a 1k sic belt. Got a bur, flipped got another bur. Used the platen to contact the spine first and carefully placed the edge on the belt. I used a 2k belt after that and cleaned up the 1k scratches, went to paper wheel with white compound. Did a few passes on that. And then to a balsa pasted crox strop I use for knives. Then to .25 diamond spray on balsa. Then to hanging leather. It shaved! Now it is not as keen as Im used to nor as smooth. It was a rough shave. Kinda like the edges that we see on the factory ZYs coming from China. BUT it was what i would say is "shaveable". Im not advocating that everyone burns their stones and does it this way. BUT Im saying that with some tweeking Im sure it could work. Maybe some lapping film belts? A turned balsa wheel with crox on a slow speed grinder? I dont know and am not going to pursue this any further. But thats my take. I use my grinder with a speed control. And my wheels are spinning away from me not towards me like they are usually. If you decide to do this just know that you have to be very careful placing the blade. If the wheel catches it you may be in a world of hurt. Anyway Im going to take that same razor and do a one tomo to finish on a jnat and see what that does. I want to add though that the first time anybody attempts anything you cant expect stellar results. Its extremely likely with some tweaking that it can work much better than what I have done here. As i said Im not interested in pursuing this any further.
ITS ALIVE!
- Thread starter buca3152
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It would be intresting to see how close your tomo finish will align with the new belt cut bevel.
*Steve Martin voice* You are a wild and crazy guy! 
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I had to do it once! Lol.*Steve Martin voice* You are a wild and crazy guy!
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I just attempted this. I raised a small slurry on a hard takashima that I have. The edge is short. No contact which is pretty much in line with the zys. It's a half bevel off. Tape? Never! Lol. So this turned out to be all for nothing. Unless I can get someone to put a jnat on a lathe and spin that bad boy into a wheel! Lol. Nothing ventured nothing gained. I rate this experience from 1 to 10 as a 0. Lol.
Lol. Not too surprising, the paper wheels are tough to keep a precise angle on. I'm guessing any stropping you did on balsa probably didn't even hit the apex. And you'd need an AWFULLY big JNat chunk to get a decent sized wheel, haha.
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True! No doubt the flat strop did nothing. I got it out of my system! Been thinking on this for a while. I'm sure a knife can be made to shave. No spine and angle selection is pretty wide open. I don't think it's necessary though. But I'm sure it can be done. I would imagine if the demand for shave ready razors was large enough and people demanded a decent edge. Edge pro on a flat ground razor "knife" should be able to although I don't have one.
Yes, I've shaved with pocket knives plenty of times while camping back when I used to do that more. It's actually quite easy with a good high level edge even with a much more obtuse bevel than a razor. I usually keep my knives around 25°-30° inclusive and they shave quite comfortably there. It probably helps that they have a major smile where I normally shaved with a knife, right where the tip curves around. Less in contact at once and all. Does take a few extra swipes though since the path is so narrow.
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Im sure. The biggest drawback to making them that way would be stropping to someone who is unfamiliar with stropping knives. But it isnt too difficult. I guess we shall leave the razors as they are then? SHave with razors and use our knives for other tasks. It isnt broken!
Yep, you got it! 
Slash McCoy
I freehand dog rockets
Awwww I wanted to see your new Jnat wheel.
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I saw a jnat shaped flat for a turntable hone once on a Japanese stone sellers site. I'm sure there's more than one out there! Long time ago. Don't even remember how much it was either.
Razors are far to hard and brittle to sharpen with a belt sander, you will never get a chip free edge. Same reason I don't like to approach the apex with very coarse stones, the chance of fracturing the steel along the apex is too high.
This is an issue with traditional carbon steel Japanese chisels too. Using hard binder synthetic stones can cause micro-fractures along the edge that propagate in use, causing chipping. Not good.....
You can get a shaving edge on a knife, but unless it's a pretty high end one with very hard, fine carbide steel, it's not going to last long and won't ever take a really fine edge. Most knife steels have large carbides for abrasion resistance, and hence cannot be sharpened to a fine apex like small carbide steels. The carbides tear out, leaving a swiss cheese effect along the apex.
This is an issue with traditional carbon steel Japanese chisels too. Using hard binder synthetic stones can cause micro-fractures along the edge that propagate in use, causing chipping. Not good.....
You can get a shaving edge on a knife, but unless it's a pretty high end one with very hard, fine carbide steel, it's not going to last long and won't ever take a really fine edge. Most knife steels have large carbides for abrasion resistance, and hence cannot be sharpened to a fine apex like small carbide steels. The carbides tear out, leaving a swiss cheese effect along the apex.
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There's are no chips in the edge. I waxed the belt. I use speed control so I would estimate half speed (1700 or so rpm). It's isn't conventional I know. I've sharpened more than a few knves of all types. I don't follow your steel argument. Or at least I haven't seen it first hand. From cheap $10 knives up to $100 or so super steel ones. And I've done them freehand, belt sander, and with paper wheels. The exceptions I've heard for power tool sharpening are some Japanese steels. But I don't have any of those. I have knives from 1095 to s90v. No issues with this tearout you speak of. On leather belt or paper wheel. As a matter of fact I can say with almost 100% certainty that these are all sharpened unconventionally (on a belt or a wheel).
Takes an electron microscope to see what's going on, alas. A light microscope cannot resolve the carbides, nor the cracks and chips in the edge, they are only visible at about 5000x or so.
Of all the stainless knife steels I know about, only 13C26 has very small carbides -- because it's really the steel used for razor blades! The rest all have fairly to very coarse carbides (for very coarse, think D2). CroMoVa, the typical steel in "German" cooking knives has very coarse carbides, and is only hardened to RC 56 or so, so the edge failure mode is bending, not chipping. Attempting to sharpen to a fine edge results in carbide loss on the edge, leaving the base steel which flattens quickly in use. That's why you can restore the edge on those knives, and other fairly soft steels, with a smooth "knife steel" -- it bends the edge back up straight when used properly. Those coarse carbides, though, when they stay put, provide excellent abrasion resistance, so the edge stays moderately sharp with steeling for a long time. Never "razor sharp" but nowhere near as dull as the chipped edge.
1095 at RC 61 chips rather then bends, but it also get much sharper (ditto for the Japanese carbon knife steels). All the "plain" carbon steels have very fine carbides, it's the chrome and vanadium that tend to be large carbide formers I think.
Belts and stones give different edges, so do different operators. I suspect a skilled honer can get a very good edge on belts, but stones with similar skill will probably have a finer edge. I don't know of anyone who has sacrificed enough good knives for the electron microscope examination to know for sure. Not everyone is going to break a knife up to get a piece small enough to look at in the EM.
Of all the stainless knife steels I know about, only 13C26 has very small carbides -- because it's really the steel used for razor blades! The rest all have fairly to very coarse carbides (for very coarse, think D2). CroMoVa, the typical steel in "German" cooking knives has very coarse carbides, and is only hardened to RC 56 or so, so the edge failure mode is bending, not chipping. Attempting to sharpen to a fine edge results in carbide loss on the edge, leaving the base steel which flattens quickly in use. That's why you can restore the edge on those knives, and other fairly soft steels, with a smooth "knife steel" -- it bends the edge back up straight when used properly. Those coarse carbides, though, when they stay put, provide excellent abrasion resistance, so the edge stays moderately sharp with steeling for a long time. Never "razor sharp" but nowhere near as dull as the chipped edge.
1095 at RC 61 chips rather then bends, but it also get much sharper (ditto for the Japanese carbon knife steels). All the "plain" carbon steels have very fine carbides, it's the chrome and vanadium that tend to be large carbide formers I think.
Belts and stones give different edges, so do different operators. I suspect a skilled honer can get a very good edge on belts, but stones with similar skill will probably have a finer edge. I don't know of anyone who has sacrificed enough good knives for the electron microscope examination to know for sure. Not everyone is going to break a knife up to get a piece small enough to look at in the EM.
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The name of the game for me anyway is that I can put an excellent edge on a knife for what my purpose is whether it's the kitchen or general use. Now if what your saying is true then these fancy expensive knives that cut so well are broken? Lol. And they arrive that way from their makers as they are all done on wheels or belts?
Top end knives aren't supplied ready to use, it's assumed the end user will sharpen to suit themselves. Even lower end Japanese knives aren't considered finished as shipped, and most of them really need some thinning behind the bevel. Actual use and user preference determine the finish grit and polish (or lack of it).
CroMoVa knives in general don't have steel that benefits from a highly polished edge nor the geometry to support one, and a belt finish works very well for them.
I prefer those freakishly sharp Japanese knives, and put up with the fragility of the edges in return for the ease of use. I finish my VG-10 knives to 6k as a rule and strop them on chromium oxide loaded hardwood after honing. Much more like a straight razor with a 20 degree included bevel angle than a Wustie at 40 degrees.
Running a good Japanese knife on a 1k belt will probably result in a "chippy" edge -- this was a big complaint about Global knives when they started selling VG-10 knives. Probably a combination of incorrect heat treatment and rough sharpening.
CroMoVa knives in general don't have steel that benefits from a highly polished edge nor the geometry to support one, and a belt finish works very well for them.
I prefer those freakishly sharp Japanese knives, and put up with the fragility of the edges in return for the ease of use. I finish my VG-10 knives to 6k as a rule and strop them on chromium oxide loaded hardwood after honing. Much more like a straight razor with a 20 degree included bevel angle than a Wustie at 40 degrees.
Running a good Japanese knife on a 1k belt will probably result in a "chippy" edge -- this was a big complaint about Global knives when they started selling VG-10 knives. Probably a combination of incorrect heat treatment and rough sharpening.
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So tell me. What is a "good edge" capable of? Shaving hair? Cutting thin paper? Because all of these things are easily accomplished using the tools I am using. Please tell me if I'm missing something. And without chips. Now I know using these types of tools can damage a knife something fierce if used improperly. But if they aren't damaged, temper blown or chippy then what? Lol.
I think you guys are not quite on each other's wavelength. I believe Fred was talking about belt grinding creating troubles with some steels at certain hardnesses. That does happen but I think only on relatively coarser belts and when they're sharpened edge leading. Paper wheels are used the other way 'round like a buffer - edge trailing. Most of the knife manufacturers that sharpen on belts also do a finishing step on a buffer or something similar.
Sharpening on stones can definitely produce a wicked shaving edge on knives, just the same as on razors. The knives with steels that have the carbide issues are pretty darn evident right from the start - they feel like glass on the hones and very little swarf is produced. Stuff like S35V and higher, T15 and certain other high speed steels, etc. I myself made a razor from one of the high speed steels - it was a bear to set the bevel on. I ended up using a diamond plate. The Chosera 1k barely did a darn thing.
Todd Simpson has a good blog with EM photos showing structure of some of the steels with prominent carbides - they seem to stay put fairly well. One exception that I'm aware of is high tungsten alloys. Those tend to not have a very good grip on the tungsten carbides.
Sharpening on stones can definitely produce a wicked shaving edge on knives, just the same as on razors. The knives with steels that have the carbide issues are pretty darn evident right from the start - they feel like glass on the hones and very little swarf is produced. Stuff like S35V and higher, T15 and certain other high speed steels, etc. I myself made a razor from one of the high speed steels - it was a bear to set the bevel on. I ended up using a diamond plate. The Chosera 1k barely did a darn thing.
Todd Simpson has a good blog with EM photos showing structure of some of the steels with prominent carbides - they seem to stay put fairly well. One exception that I'm aware of is high tungsten alloys. Those tend to not have a very good grip on the tungsten carbides.
