D2 sharpness vs. sharpening medium

Personally I agree, diamond is the best way to sharpen high carbide steels like D2. However I think you'll also find many knife-knowledgeable folks who like regular SiC and AO stones for the toothy, working edge you can get that's good for slicing.

FWIW, CPM D2 is a whole different story, out of curiosity I sharpened one on a Norton medium India stone and it took a beautiful edge with little evidence of chippiness. Obviously it's quite fine grained, and a nice steel to use.
 
dmt fine for profiling, blue & champagne belgian coticules (garnet stones) for sharpening, and they are the best thing I've found for hard steels in general. I don't care for the 'scratchy' look that diamond leaves, whereas the garnet stones leave a mirror polished edge as well as a sharp one. I burnish after sharpening with a tiny surgical arkansas stone, just for drill (and edge longevity) .

I own a kershaw outcast, and 3 ek #2 daggers, and 2 RAT-3's in D2.. they'll go past toothy with the RIGHT sharpener, and if you aren't going to spring for a belgian coticule, the only other flat hone i know would be effective is a DMT 8000 grit, which I don't own and keep meaning to buy.. in any case the garnet is 'hard enough' to polish off the carbides instead of ripping them loose, and i've not experimented with enough hones to know what else is. diamond and garnet work well enough, and i suspect that diamond paste on a paddle strop is as good an answer as any for a 'smooth' edge. . but the right natural stone will do it, supposing you're that variety of sharpener.
 
Just got a BM710D2. Not at all impressed with factory edge... toothy burr still present and visible to the eye. Used a small extra fine DMT DIASHARP to get most of the burr sorted. Finished her up nice and smooth and poppin' sharp with Tormek's Honing Compound and light oil on a leather strop. First time I've used the Tormek compound and I must say I'm impressed, it really does what is written on it: "Gently removes burr and polishes the edge to razor sharpness". Even D2.
 
I have always said that carbide size does not determine ultimate sharpness or limits the polish of the edge. D2 has an average carbide size of around 20 microns plus. If that were a limiting factor, you should never get D2 to shave at all (forget about hair-wittling). Many modern abrasives are perfectly capable of shaping and sharpening carbides, diamonds in particular have no problems doing that. It's just like Sodak said, it is only a matter of time and effort you are willing to put into it.

A different question is how long the edge will last, as the large carbides will destabilize a fine edge in general, but that is something that you hardly going to notice if you do no more (or not much more) than shaving. It is also a different question how low an edge angle you can put on a certain steel. I would imagine that once you pass a certain acuteness, you are limited in polish you are able to achieve as the carbides may already break out of the edge while sharpening.
 
Here is the chart previously posted by Mr. Landes to provide a visual for that last post by HoB.
 

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HoB said:
I have always said that carbide size does not determine ultimate sharpness or limits the polish of the edge. D2 has an average carbide size of around 20 microns plus. If that were a limiting factor, you should never get D2 to shave at all (forget about hair-wittling). Many modern abrasives are perfectly capable of shaping and sharpening carbides, diamonds in particular have no problems doing that. It's just like Sodak said, it is only a matter of time and effort you are willing to put into it.

A different question is how long the edge will last, as the large carbides will destabilize a fine edge in general, but that is something that you hardly going to notice if you do no more (or not much more) than shaving. It is also a different question how low an edge angle you can put on a certain steel. I would imagine that once you pass a certain acuteness, you are limited in polish you are able to achieve as the carbides may already break out of the edge while sharpening.
Click to expand...


I guess I tend to differentiate between shaving smooth edge and shaving acute angle.

I pretty much don't sharpen at less than a 30° inclusive angle. I find that works pretty good for me. Shaving and ultimate sharpness is not my thing.

How do you guys find the stability of D2 at 30° polished smooth?
 
30 deg should work great. I found stability issues going below 20, around 15 or so. Above 20, it seemed fine, as long as common sense was applied, depending upon the relief behind the edge.
 
sodak said:
30 deg should work great. I found stability issues going below 20, around 15 or so. Above 20, it seemed fine, as long as common sense was applied, depending upon the relief behind the edge.
Click to expand...


Thanks! Just what I needed to know.

Thanks to all who have taken time to educate me on this stuff.
 
For what it's worth, this picture was completely my fault. I kept taking the angle down to see what it could do performance-wise. Once I got damage, I put on a microbevel. I lost about 5% of the cutting ability, but gained a tremendous increase in strength. No more damage doing the same tasks.

This knife is a rope and cardboard cutting monster, no joke. It will cut seemingly forever on abrasive materials. Doing all this confirmed for me, that having a very thin relief with a relatively thick edge angle (microbevel) is the way to go with D2. That's pretty much what Dozier does, and he knows what he's doing.

Here's what can happen at 15 included, cutting fuzz sticks with a "scooping" motion:

http://i137.photobucket.com/albums/q203/sodak_photos/queen_4180.jpg

It took about 2-3 minutes on a DMT blue/red to take out almost all the damage, due to the thin relief. Sharpening this knife with a microbevel is pure joy, even though it's D2, it only takes a minute or two on a DMT blue/red.

Again, the damage was my fault. I was looking for it's limits, and found it. I backed off slightly, and continue to enjoy this knife today.
 
Could someone explain what is toothy and fine?

I use a DMT Aligner jig for rebeveling D2 Queen slipjoints.
I start with DMT extra course to extra fine (green)
It is a wonderful no-brainer to use.
It mostly comes of the jig sharp enough to whittle hair.

I can see the grind marks from the extra fine on the bevel.
Is this toothy or fine?
 
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