Finer grit addition for VC/WC steels

samuraistuart

samuraistuart

Joined
Dec 21, 2006
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There are several of you here that I highly value your input. I'll forget a few of you if I start naming names! Anyway, I need to add a finer grit stone to my lineup for more wear resistant steels, something in the 3 micron range. Doubtful I will be sharpening any S90V/S110V and the like anytime soon....mainly need something that will easily handle S35VN/Elmax type steels in the finer grits. Would like to NOT use CBN/diamond/strop...prefer to stick with stones...but I'm flexible.

Current line-up for wear resistant steels: DMT XXC, XC, C, F, EF also Atoma 140, 400, 600, 1200. Also have the Spyderco F and UF stones...I realize they are ceramic and harder than VC/WC (viet cong/wiet cong!), but they "seem" to be given a run for their money on hard Blue2, O7, Cru Forge V alloys (63HRC+).

Also in my line-up: Crystolon C/F, India C/F, Chemical 320, Naniwa SS 400, Shapton Pro 1000, Norton 1000, King 4000, Suehiro 8000 (nice stone!), Chinese 12k.

What would you add to go finer than the 1200 mesh (~9 micron) that would easily handle Elmax type steels, and handle possible S90V type steels in future? I may have to go with the diamond/CBN emulsions, but maybe the Shapton glass 6000 would work just fine for Elmax/S35VN type? I'm open to any stone suggestion, and open to emulsions of you think that's best.

(Concerning DMT MEF and EEF. Would prefer to stay away from those, as I hear a few reports of inconsistent scratch patterns/abrasive. I experience that on their 1200 EF stone, don't care for it)

Thanks in advance!
 
I like the EEF DMT, that would be my first recommendation. Have had good luck with mine and occasionally use it on wide bevel woodworking stuff - it makes a nice finish. On the really high VC steel it does an excellent job for microbevels on a thin cutting bevel. It is a good tool to have on those types of steels.

After that you're really bucking what is known and proven to work. I have a silicon carbide Suehiro 8k that works well on stainless but still has trouble with anything tougher then s30v. It works, but is not the same as diamond.

Diamond lapping films over a hard surface have given me good results and last a long time if not abused.

The Spyderco ceramics are not harder than VC and possibly not even WC IIRC, though they work through a combination of grinding and burnishing.
 
HeavyHanded said:
The Spyderco ceramics are not harder than VC and possibly not even WC IIRC, though they work through a combination of grinding and burnishing.
Click to expand...

Wow, that's really surprising. I had assumed for quite some time that the Spyderco ceramics would cut pretty much any modern steel, including those with Vanadium Carbides in them. ...and I mean cut, not "abrade away the matrix until the carbides fall or tear out". Five minutes of research says that Sapphire (which is what's in Spyderco ceramics) are 1800 to 2200 Knoop hardness, while VC is 2600 and WC is 1880.

So, apparently, Spyderco ceramics can NOT cut Vanadium Carbides and will have a rough time with Tungsten Carbide, as the hardness is so close. I have learned a new nugget of information. :)

Brian.
 
The Spyderco ceramics will abrade VC. The VC will just abrade the ceramics faster. Abrasion between hard/soft is not a 0%/100% interaction. It is not ideal, but it can be done.
 
I also am curious about huge grit options. I have some S110V that won't get quite a sharp as I'd like off the Sharpmaker.
 
Spyderco ceramics are Aluminum oxide at heart, and because of this they struggle with VC.

Even my Shapton Glass stones struggled past 500-1000 grit on anything over 4% VC, again because they are aluminum oxide as the main abrasive. Steels with wolfram sharpen a lot better but you will want a tight progression otherwise getting the previous scratches out can be a pain. It doesn't seem to be as troublesome as VC though.

Typically, I finish with a coarse DMT or SG500 and strop with 1-3 micron diamond on balsa. Personally, I don't see the point in making them any more refined as it just makes them perform worse.
 
me2 said:
The Spyderco ceramics will abrade VC. The VC will just abrade the ceramics faster. Abrasion between hard/soft is not a 0%/100% interaction. It is not ideal, but it can be done.
Click to expand...

I used to think that too till eKretz took some excellent pics. Here's one with his UF on HSS, not even Vanadium carbide, more likely Tungsten:

13%20Spyderco%20UF%20Raking%20Light.jpg


This thread should be a sticky
http://www.bladeforums.com/forums/s...V-S90V-CTS204P-etc)/page3?highlight=stropping
 
Would you include VG-10 steel in this lineup? I find it slower to sharpen with default Lansky stone, but not that slow.
 
malaverdiere said:
Would you include VG-10 steel in this lineup? I find it slower to sharpen with default Lansky stone, but not that slow.
Click to expand...

VG-10 doesn't have enough, if any, vanadium or tungsten to be significant in carbides (VC, WC). It's only significant wear resistance comes in the form of chromium carbide; and that's not much of an obstacle to sharpen with aluminum oxide (India stones, alumina ceramics, etc).

The main speed limitation with Lansky's hones is their very small size; any small increase in hardness or wear resistance of the steel will be more noticeable with such a small hone.


David
 
Last edited:
Also have the Spyderco F and UF stones...I realize they are ceramic and harder than VC/WC (viet cong/wiet cong!), but they "seem" to be given a run for their money on hard Blue2, O7, Cru Forge V alloys (63HRC+).
Click to expand...

The Spyderco ceramics are not harder than VC and possibly not even WC IIRC, though they work through a combination of grinding and burnishing.
Click to expand...

I have used my Spyderco UF Triangle Rod on 3V almost elusively and it is starting to peter out and just burnish so probably not the best for the higher VC stuff. Not that I have much experience with those.

One view I have is M390 is sharpenable by just my Shapton Glass and that steel is pretty super so I have settled down into that nice mud hole where my steel likes my stones and my stones like my steel and the steel is fantastic.
 
HeavyHanded said:
I used to think that too till eKretz took some excellent pics. Here's one with his UF on HSS, not even Vanadium carbide, more likely Tungsten:

13%20Spyderco%20UF%20Raking%20Light.jpg


This thread should be a sticky
http://www.bladeforums.com/forums/s...V-S90V-CTS204P-etc)/page3?highlight=stropping
Click to expand...

I'm not sure what that's supposed to show? I've seen diamond grinding wheel grits dulled by grinding WC. Not knocked off, but worn flat like a mountain with the peak cut off. There is abrasion on both sides, just much more on one than the other. Again, it doesn't make it optimal or even practical, but it's doable.
 
me2 said:
I'm not sure what that's supposed to show?
Click to expand...

Take a look at the linked thread. It shows some before and after pictures. Essentially, the pictures from the Spyd UF show that it has only mildly reduced the macro scratch pattern, but has introduced the black thin "streaks" in the steel, which might be as a result of the carbides tearing out and then cutting through the steel matrix as they become part of the abrasive surface. This last sentence is purely my own speculation. Look at the before and after pictures and see what you think.

Brian.
 
There're reports that new DMt EEF (8000) is too sharp & doesn't yield finer scratch patterns than EF (1200).
I can tell it's true. However a smoothed out DMt EEF works better than Spyderco UF for VG10.
Luong has tips on smoothing down the EEF. I simply did that by using it to rebevel (i.e. wearing down much steel).

Highly recommended EEF as you have Spyderco UF already. Sometimes the UF can help breaking off burrs, but has to be high angle edge leading feather light pass. Not good when I'm tired & impatient.
 
me2 said:
I'm not sure what that's supposed to show? I've seen diamond grinding wheel grits dulled by grinding WC. Not knocked off, but worn flat like a mountain with the peak cut off. There is abrasion on both sides, just much more on one than the other. Again, it doesn't make it optimal or even practical, but it's doable.
Click to expand...

bgentry said:
Take a look at the linked thread. It shows some before and after pictures. Essentially, the pictures from the Spyd UF show that it has only mildly reduced the macro scratch pattern, but has introduced the black thin "streaks" in the steel, which might be as a result of the carbides tearing out and then cutting through the steel matrix as they become part of the abrasive surface. This last sentence is purely my own speculation. Look at the before and after pictures and see what you think.

Brian.
Click to expand...

That's it. Maybe some shaping of the carbides but the density of pitting, the absence of anything but slightly excavated carbides and then holes where they were, pronounced dig tracks from the carbides, show mostly they are not being shaped to any extent.

Yes carbides will wear on AlOx and maybe to a slightly greater extent on SIC, but for true carving of them you really need a super abrasive, esp as the grit size becomes equal to or smaller than the carbides. On most stones, the abrasive only stand 10% proud, so a 20-30 micron abrasive only 2-3 micron scratch depth/path. This fits with a lot of anecdotal reporting 600-800 ANSI about tops before needing to switch to a super abrasive for best results.
 
Chris "Anagarika";16616708 said:
There're reports that new DMt EEF (8000) is too sharp & doesn't yield finer scratch patterns than EF (1200).
I can tell it's true. However a smoothed out DMt EEF works better than Spyderco UF for VG10.
Luong has tips on smoothing down the EEF. I simply did that by using it to rebevel (i.e. wearing down much steel).

Highly recommended EEF as you have Spyderco UF already. Sometimes the UF can help breaking off burrs, but has to be high angle edge leading feather light pass. Not good when I'm tired & impatient.
Click to expand...

That makes sense, I hated my eef at first, i started using it a lot, not caring about it. Now I get a nice fine edge on many knives, kitchen included.
I now have a medium eef (4000) that I am going condition. My plan is to use it on knives at work, should provide a quicker touch up on kitchen knives that are not of the highest quality. After a bit I will try it on my lower carbide hobby knives. With the high carbide stuff , I adhere to Jason's 4% rule, coarse dmt then 1mic cbn strop.

Russ
 
Thank you all for the help, I just now checked back in on this thread. For ~4% VC steels. So the EEF DMT seems to be preferred? Diamond compounds in the 1-3 micron range after a C or F diamond stone? I'd like to hear more from all of you before I pull the trigger and purchase something. I like to get my research in before making bad/stupid decision.

Forgot application...this will be mainly for hunting knives AND kitchen knives (chef/paring/petty/santoku). Some customers like Jason's edge (polished teeth), others prefer a full on razor (progression up to 1 micron or better).
 
Um... that (purplized) is a very small well-informed violin :p

Stropping with diamond compound is complex going everywhere and nowhere at the same time because abrasives are partially embedded (could rotate and or move), plus substrate can flex & reflex (dip & crest) to produce undulated abrading topology. IF/when stropping apex with diamond/cbn, I jump directly to 0.25um size from EE.

samuraistuart said:
Thank you all for the help, I just now checked back in on this thread. For ~4% VC steels. So the EEF DMT seems to be preferred? Diamond compounds in the 1-3 micron range after a C or F diamond stone? I'd like to hear more from all of you before I pull the trigger and purchase something. I like to get my research in before making bad/stupid decision.

Forgot application...this will be mainly for hunting knives AND kitchen knives (chef/paring/petty/santoku). Some customers like Jason's edge (polished teeth), others prefer a full on razor (progression up to 1 micron or better).
Click to expand...
 
For 2-3 yrs now, I've been stubborn on 0.25um because I envision bigger abrasive = higher impact, which contribute to weaken apex decorated carbides. I think an abundant of of 25-30nm abrader (actually cutting tips) will works better on shaping carbides from 250nm to 5um in dia. Just focusing on carbides on apex, they are mostly 50% naked on bevel side, so don't dislodge them with lapping/stropping impact :p
Chris "Anagarika";16619199 said:
Luong, so the 0.25 after EEF is refined version of Jason's C & 1 micron?
Click to expand...
 
Luong,

Thanks. It explains why edge leading on smooth EEF is better than adding stropping 1 micron after. Or it might be my lack of technique. I use 1 micron you sent me, over 2 layers of paper on WB.
 
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