Sharpening S30V blade

[B.F.U]

S30v isn't that hard to sharpen with good technique, at least in my experience.

 

[Ben Dover]

This is exactly why diamond is better for these steels (probably CBN too, though I've not tried it yet). SiC can sometimes abrade high-vanadium steels, but depending on the manufacture and heat treat used on an individual blade, the vanadium carbides will usually be very hard and often harder, even compared to the SiC abrasive. Diamond is ~3X-4X as hard as SiC, and will abrade the carbides much, much more effectively. Abrasive that's not quite hard enough to really grind & shape the carbides will tend to burnish/polish/round them off, instead of truly shaping them into a fine cutting edge. I've occasionally gone back and tried SiC on S30V, but the results are exactly as you've described, and always disappointing. It 'sort of' sharpens it, in making the edge relatively crisp, but not quite hair-shaving sharpness. Using diamond after trying that, the difference in the crispness of the edge will become very apparent, very quickly.
David

Well said, David.

Diamonds will sharpen the entire blade, including the carbides. If you prefer a polished edge, as I do, finer grit water stones, sprayed with a very thin film of the same grit CBN spray will refine it quite nicely and prepare it for CBN or diamond stropping.

Note! Use only spray CBN or diamond on stones. Never use a paste. (ask me how I know that)

 

[Obsessed with Edges]

Well said, David.

Diamonds will sharpen the entire blade, including the carbides. If you prefer a polished edge, as I do, finer grit water stones, sprayed with a very thin film of the same grit CBN spray will refine it quite nicely and prepare it for CBN or diamond stropping.

Note! Use only spray CBN or diamond on stones. Never use a paste. (ask me how I know that)

Thanks Ben.

And OK, I'll bite. I'm curious as to your impressions about using (not) paste on stones? I haven't yet tried using my Dia-Paste or any other compounds on any stones (just on wood strops), but now I'm curious as to your impressions on this. Thanks!


David

 

[Ben Dover]

Thanks Ben.

And OK, I'll bite. I'm curious as to your impressions about using (not) paste on stones? I haven't yet tried using my Dia-Paste or any other compounds on any stones (just on wood strops), but now I'm curious as to your impressions on this. Thanks!


David

The spray compounds rinse off after use, or just naturally drop off with the swarf. The sticky paste sticks solidly forever and is removed only with great difficulty, and swearing.

If you get an assortment of the higher grit CBN, say, from 8 micron down you will have a spray that approximates the grit of the stone.(IOW, close enough!)

i.e. 3 micron to 4000 water stone
1 micron to 8000 etc. I don't have my chart handy, it's a home, but the conversions are on google. Just remember if using on Japanese stones to use the JIS rather than the ANSI for grit size.

Of course the same can be accomplished with a large assortment of strops, but it seems to work considerably faster with water stones.

 

[Obsessed with Edges]

The spray compounds rinse off after use, or just naturally drop off with the swarf. The sticky paste sticks solidly forever and is removed only with great difficulty, and swearing.

If you get an assortment of the higher grit CBN, say, from 8 micron down you will have a spray that approximates the grit of the stone.(IOW, close enough!)

i.e. 3 micron to 4000 water stone
1 micron to 8000 etc. I don't have my chart handy, it's a home, but the conversions are on google. Just remember if using on Japanese stones to use the JIS rather than the ANSI for grit size.

Of course the same can be accomplished with a large assortment of strops, but it seems to work considerably faster with water stones.

Thanks Ben. I sort of wondered if difficulty of removal/cleaning had something to do with that.

I suppose the flip-side to that is, it's good to know the paste really does hang on, when used with strops that hopefully won't have to be re-loaded too frequently. I had sometimes wondered how much of the compound stays put, and how much gets scrubbed off in use, or wiped off during cleaning of strops. Sounds like it's pretty tenacious stuff.


David

 

[Ben Dover]

Thanks Ben. I sort of wondered if difficulty of removal/cleaning had something to do with that.

I suppose the flip-side to that is, it's good to know the paste really does hang on, when used with strops that hopefully won't have to be re-loaded too frequently. I had sometimes wondered how much of the compound stays put, and how much gets scrubbed off in use, or wiped off during cleaning of strops. Sounds like it's pretty tenacious stuff.


David

I use a lot of paste in leather. I even tried it on hardwood. It worked on the hardwood, but leather and cork are easier to use.

And yes, the paste is tenacious.

 

[vijaykumarvictor]

Man I'm loving this, all this information and experiences. Now I can do something specialized instead of mucking around with sic anymore. The other day an old timer showed off his D2 slice a piece of paper, the angle of the cutting edge was not too modified for this task alone. The sound that his knife made was really sweet, unlike mine that kind of shrieks. Can somebody please recommend me some value for money diamond tools that I'll require. Thank you.

 

[bodog]

Congress has some diamond (if I remember right) and ceramic stones. I'll look more into them, thanks for the heads up. As far as the sic stones, Phil Wilson said that they're his favorite and he takes S90V and S110V to about 6 points harder than what my knife is. Do you think that he prefers the very toothy type of sharp I'm talking about? I know it's a little bit of conjecture, but I'm serious, I spent about 6 hours total sharpening and polishing mine just trying to get it to shave the hair on my arm. To be fair, it slices cardboard like it's nothing, easier than a fine edge, and whenever I slice, not push cut, paper, it seems to do it easier than any other knife I have, maybe I should quit and leave it be.

I'm sure you guys are right about the carbides not being shaped, just trying to figure out why Phil Wilson would like them so much without him being here to ask. That and I'm guessing my strop paste isn't the best. I got it from a lapidary supply place and I'm betting it's not actually diamond paste, though they use "dia" in the name. My fault for not checking when I bought it.

 

[Obsessed with Edges]

Congress has some diamond (if I remember right) and ceramic stones. I'll look more into them, thanks for the heads up. As far as the sic stones, Phil Wilson said that they're his favorite and he takes S90V and S110V to about 6 points harder than what my knife is. Do you think that he prefers the very toothy type of sharp I'm talking about? I know it's a little bit of conjecture, but I'm serious, I spent about 6 hours total sharpening and polishing mine just trying to get it to shave the hair on my arm. To be fair, it slices cardboard like it's nothing, easier than a fine edge, and whenever I slice, not push cut, paper, it seems to do it easier than any other knife I have, maybe I should quit and leave it be.

I'm sure you guys are right about the carbides not being shaped, just trying to figure out why Phil Wilson would like them so much without him being here to ask. That and I'm guessing my strop paste isn't the best. I got it from a lapidary supply place and I'm betting it's not actually diamond paste, though they use "dia" in the name. My fault for not checking when I bought it.

If the carbides in the steel are relatively small (say 2 microns or less; this is possible with CPM steels), it's still possible to create good or even great toothy edges, if the stones are essentially shaping the steel matrix itself and exposing the carbides more or less 'as is'. If so, this could be done with SiC or other relatively modern abrasives (maybe aluminum oxide also; especially if the edges are applied on powered equipment, as most new blades are done). I still believe if one wishes to take these steels finer, to shaving/hair-whittling (literally), there'll be some need to start shaping the carbides to something smaller than their original size, down to < 1 micron wide at the apex. For that, I'd still much prefer diamond to get it done with some predictability and consistency. I don't have any idea what type of edge Phil Wilson prefers, whether toothy or more polished, though I'd bet it's the former. This seems to be what many makers 'prefer' in high-wear steels anyway, with relatively large and hard carbides. The good 'working edges' attributed to these steels are usually somewhat coarse from the factory. I have one Phil Wilson folder in S30V, and it's edge came rather coarse; don't know if that's typical of his blades overall. That particular knife is actually one that I'd had some difficulty with, in trying to use SiC wet/dry paper to refine & thin the edge.


David

 

[bodog]

Thanks for the info. I think I'll just be happy with getting razor edges on my other knives and keep this one like it is, a great but unrefined cutter. Does S30V perform the same (edit: nevermind, saw the other post saying it did). I've sharpened up an S35VN blade and it could get sharp but was a poor cutter because of the edge geometry. S60V acted quite a bit like the S110V but I could get a brighter finish on it vs the 110V. Honestly, the best edges I've gotten were on CPM154, 154CM, and crmov steels. D2 stayed pretty gritty, too, so yea, I can definitely see what you're talking about now that I think about it. When you say the carbides are about 2u, that means that any diamond or boron carbide strop under the 2u should be able to cut em down, right? If so, then I know my strop paste is bunk because I go down to 1u.

 

[Obsessed with Edges]

Thanks for the info. I think I'll just be happy with getting razor edges on my other knives and keep this one like it is, a great but unrefined cutter. Does S30V perform the same (edit: nevermind, saw the other post saying it did). I've sharpened up an S35VN blade and it could get sharp but was a poor cutter because of the edge geometry. S60V acted quite a bit like the S110V but I could get a brighter finish on it vs the 110V. Honestly, the best edges I've gotten were on CPM154, 154CM, and crmov steels. D2 stayed pretty gritty, too, so yea, I can definitely see what you're talking about now that I think about it. When you say the carbides are about 2u, that means that any diamond or boron carbide strop under the 2u should be able to cut em down, right? If so, then I know my strop paste is bunk because I go down to 1u.

To some extent, even larger grit abrasive can at least begin to refine smaller carbides. Depending on the backing/substrate used on the strop, larger grit particles will perform at a smaller 'effective' grit, due to the effects of the grit embedding more deeply into softer substrate, and even being somewhat 'cushioned' by it. As the substrate becomes firmer, grit won't embed as deeply or deflect away as much under pressure, so it'll start cutting & performing closer to it's rated grit size. Consider if you compared a 3-micron diamond hone (hard steel under nickel, with grit embedded in it) to 3-micron diamond grit used on a leather strop, the strop's grit won't be nearly as aggressive a cutter, as compared to the unyielding grit of the hard hone. So, you could use the 3-micron hone essentially to it's refining limits, then do additional refining & polishing with identical 3-micron grit on a strop.


David

 

[Ezmyrian]

I don't wish to hijack this post from Vijay, but I had a related question. I am currently looking at the Bear OPS MC-110-B7-T-SR knife and consequently, for a good setup for keeping it sharp and potentially re-profiling the edge. (if you have a similar knife you think would be better, I'm open to suggestions, as I have not purchased it yet. I wanted cpm-s30v steel, partial serrations, liner lock, and an easy one-hand open/close system and it fits that bill, but I'm still woefully new to good knives.) I've read several places that the Sharpmaker by spyderco is good for maintaining an edge, but not for re-profiling. Also, it's $100 for the SM, and I am on a budget and trying not to spend more than I need to in order to get the job done right. If it is really THAT good, I will consider it a sound investment that will pay for itself in savings for years to come. Being woefully new to this stuff, I would appreciate links to any suggested items. I've been reading for 8+ hours on several sites, and been unable to find the majority of the items people have posted about. Fx:

This is exactly why diamond is better for these steels (probably CBN too, though I've not tried it yet). SiC can sometimes abrade high-vanadium steels, but depending on the manufacture and heat treat used on an individual blade, the vanadium carbides will usually be very hard and often harder, even compared to the SiC abrasive. Diamond is ~3X-4X as hard as SiC, and will abrade the carbides much, much more effectively. Abrasive that's not quite hard enough to really grind & shape the carbides will tend to burnish/polish/round them off, instead of truly shaping them into a fine cutting edge. I've occasionally gone back and tried SiC on S30V, but the results are exactly as you've described, and always disappointing. It 'sort of' sharpens it, in making the edge relatively crisp, but not quite hair-shaving sharpness. Using diamond after trying that, the difference in the crispness of the edge will become very apparent, very quickly.

I used to think S30V and similar steels were difficult, and I just couldn't get excited about such steels. But that was mainly due to my not understanding the limitations of the SiC abrasive I was trying to use on it. After finally realizing the advantages of using the right abrasive (diamond) on it, S30V has suddenly become very easy to deal with. It responds greatly to something like a DMT 'Fine' and, using only that grit, touching up these knives is a breeze.

David

When David says DMT 'Fine', is he talking about bench stones, blocks, rods, files? This is why links are especially useful to me. I'm sorry if I am asking newbie questions, but I want to do this right, rather than have to do it twice. Also, any power equipment is out as I do not have a shop I can use, so it all has to be things I can do by hand. Thanks in advance!

 

[David Martin]

S30V or S60V is not difficult to sharpen on a large SiC stone or Norton's fine India stone. To reprofile these steels is another matter. Although it can be done it takes more time. Still, I didn't notice working it on a diamond stone was any faster. They all load up and need cleaning for the work to progress. Norton's large JUM-3 stone in SiC can be delivered to your door is under 50$ and is 2 grits. The same size diamond stone in coarse or X-coarse is 80$ and is a single grit. So, your call. DM

 

[Jens Schuetz]

I don't wish to hijack this post from Vijay, but I had a related question. I am currently looking at the Bear OPS MC-110-B7-T-SR knife and consequently, for a good setup for keeping it sharp and potentially re-profiling the edge. (if you have a similar knife you think would be better, I'm open to suggestions, as I have not purchased it yet. I wanted cpm-s30v steel, partial serrations, liner lock, and an easy one-hand open/close system and it fits that bill, but I'm still woefully new to good knives.) I've read several places that the Sharpmaker by spyderco is good for maintaining an edge, but not for re-profiling. Also, it's $100 for the SM, and I am on a budget and trying not to spend more than I need to in order to get the job done right. If it is really THAT good, I will consider it a sound investment that will pay for itself in savings for years to come. Being woefully new to this stuff, I would appreciate links to any suggested items. I've been reading for 8+ hours on several sites, and been unable to find the majority of the items people have posted about. Fx:



When David says DMT 'Fine', is he talking about bench stones, blocks, rods, files? This is why links are especially useful to me. I'm sorry if I am asking newbie questions, but I want to do this right, rather than have to do it twice. Also, any power equipment is out as I do not have a shop I can use, so it all has to be things I can do by hand. Thanks in advance!

8hours research? That's a lot of money if you think of it as work time. How about spending less time and jumping right in?
Just get an edge pro it's even easier than the sharp maker [which is already easy (I own both)]. The edge pro sharpens and reprofiles.
Even I can use that device and get shaving sharp. There are also others out there which some prefer like the wicked edge for example. So I guess my advice didn't save you any time since now you'll have to do even more research
Sorry

 

[Obsessed with Edges]

(...)
When David says DMT 'Fine', is he talking about bench stones, blocks, rods, files? This is why links are especially useful to me. I'm sorry if I am asking newbie questions, but I want to do this right, rather than have to do it twice. Also, any power equipment is out as I do not have a shop I can use, so it all has to be things I can do by hand. Thanks in advance!

DMT's 'Fine' is what they rate as '600 Mesh' or 25 micron grit size; color-coded RED. Their grit ratings are consistent across the entire line (bench stones, pocket/portable hones, rods, diamond 'steels', etc.). Here's a copy of their grit chart:

David

 

[Ezmyrian]

David Martin: I've read in several posts in forums that using SiC didn't work well with s30v and similar steels. Something about the hardness of the SiC and s30v being so close that it was tough to get a proper sharp edge on the knife. I don't mean to second guess you, you have far more expertise than I, just a concern for me.

DMT's 'Fine' is what they rate as '600 Mesh' or 25 micron grit size; color-coded RED. Their grit ratings are consistent across the entire line (bench stones, pocket/portable hones, rods, diamond 'steels', etc.). Here's a copy of their grit chart:

David

Ah, thank you for that. It helps clear up my confusion a bit.

8hours research? That's a lot of money if you think of it as work time. How about spending less time and jumping right in?
Just get an edge pro it's even easier than the sharp maker [which is already easy (I own both)]. The edge pro sharpens and reprofiles.
Even I can use that device and get shaving sharp. There are also others out there which some prefer like the wicked edge for example. So I guess my advice didn't save you any time since now you'll have to do even more research
Sorry

Haha, I did end up doing more research because of that suggestion, but I view it as an investment in getting it right the first time. I checked out several posts about the apex pro, and I am tempted to go that route. If I do, what, if anything, do you recommend I get with it? Higher/lower grit stones, hones, polish tapes, leveling kit?

 

[Ben Dover]

Haha, I did end up doing more research because of that suggestion, but I view it as an investment in getting it right the first time. I checked out several posts about the apex pro, and I am tempted to go that route. If I do, what, if anything, do you recommend I get with it? Higher/lower grit stones, hones, polish tapes, leveling kit?

Starting out with an Edge-Pro Apex is a very wise decision. I'd suggest you get a couple of Edge-Pro "blanks" with it. Then get a 2 inch By 6 inch DMT coarse diamond plate, and glue it with 3M super 77 to the Edge-Pro blank. (I think chef knives to go has that 2X6 DMT already glued to a blank.)

The DMT will speed up reprofiling by an order of magnitude. A stone leveling kit will eventually end up on your workbench, as well as an angle cube. But they aren't absolutely necessary right at the start. The angle cube will save you a lot of work in setting bevels, though.

There are dozens of other accessories available for the EP, but get the basic unit and learn how to use it, then when you're good with it, you can decide on accessories. I've used most of the systems out there, and in my opinion, the Edge-Pro is the best and fastest road to razor-blade edges.

 

[Ezmyrian]

[/B]
Starting out with an Edge-Pro Apex is a very wise decision. I'd suggest you get a couple of Edge-Pro "blanks" with it. Then get a 2 inch By 6 inch DMT coarse diamond plate, and glue it with 3M super 77 to the Edge-Pro blank. (I think chef knives to go has that 2X6 DMT already glued to a blank.)

The DMT will speed up reprofiling by an order of magnitude. A stone leveling kit will eventually end up on your workbench, as well as an angle cube. But they aren't absolutely necessary right at the start. The angle cube will save you a lot of work in setting bevels, though.

There are dozens of other accessories available for the EP, but get the basic unit and learn how to use it, then when you're good with it, you can decide on accessories. I've used most of the systems out there, and in my opinion, the Edge-Pro is the best and fastest road to razor-blade edges.

Thanks for the info Ben. I looked on chef knives to go, but the only item I found was a double sided coarse/extra coarse plate. http://www.chefknivestogo.com/dmt2x6diplfo.html is the link. Would this work? And would I need to mount it to a blank? The video says it will fit, but I question how well it would hold it. Also, if I were to mount it on a blank, I'd be losing the extra coarse side. I kind of hate to do that, but I may have no choice. Also, I noticed that was about the same price as the single sided coarse plate from the DMT website. http://www.dmtonlinestore.com/6-Dia-Sharp-Continuous-Diamond-Bench-Stone-P16C26.aspx

Otherwise I'm looking to get the EP apex as Jens and yourself suggested with the setup you outlined. I just wanted to find out what I should do about the above issue before I got to ordering everything. I've heard it's best to buy the EP direct from their website, so that's what I'm planning. Thanks again.

 

[HeavyHanded]

S30V or S60V is not difficult to sharpen on a large SiC stone or Norton's fine India stone. To reprofile these steels is another matter. Although it can be done it takes more time. Still, I didn't notice working it on a diamond stone was any faster. They all load up and need cleaning for the work to progress. Norton's large JUM-3 stone in SiC can be delivered to your door is under 50$ and is 2 grits. The same size diamond stone in coarse or X-coarse is 80$ and is a single grit. So, your call. DM

This is a link from Phil Wilson's site - is good reading for anyone interested in how he gets it done on high carbide steels.

http://www.seamountknifeworks.com/articles/shapening.pdf

I don't have any experience of steels higher than s30v or D2, but silicon carbide works both to a very clean edge and quickly - both off a stone and on sandpaper. There are no 3u voids visible along the cutting edge indicating mineral tear-out, and stropping with SiC produces a tree-topping edge.

I would have to believe that diamonds would be best choice to go to a higher finish with these steels anyway, and especially s90 or 110v. I have reservations about using a finer polish on these steels - the bulk of endurance testing done on them leads one to believe the medium finish (600-800 or 1k JIS) produces the longest lasting edge, and perhaps a finer edge finish is best left to finer grained steels?

 

[rutcrazed]

This is a link from Phil Wilson's site - is good reading for anyone interested in how he gets it done on high carbide steels.

http://www.seamountknifeworks.com/articles/shapening.pdf

I don't have any experience of steels higher than s30v or D2, but silicon carbide works both to a very clean edge and quickly - both off a stone and on sandpaper. There are no 3u voids visible along the cutting edge indicating mineral tear-out, and stropping with SiC produces a tree-topping edge.

I would have to believe that diamonds would be best choice to go to a higher finish with these steels anyway, and especially s90 or 110v. I have reservations about using a finer polish on these steels - the bulk of endurance testing done on them leads one to believe the medium finish (600-800 or 1k JIS) produces the longest lasting edge, and perhaps a finer edge finish is best left to finer grained steels?

Hello H.H Thanks for the above link. Printed it and stored it. It almost felt like i was discussing sharpening with you. LOL