Sharpening D2 Steel

The belt sander suggestion is probably the "fastest" method but you have to be very careful. As suggested, practice on cheap knives you don't really care about messing up. I use a harbor Frieght 1x30 belt sander for reprofiling and that thing is the bees knees. You have to keep the blade cool though because you can burn the edge, especially near the tip. I used mine on this bk24 with d2 steel to reprofile to around 30 degrees inclusive with a 400 grit belt. Then a king 1k, king 6k and Chinese natural 12k just to see how sharp it would get. Scary sharp.



 
albert_ilalang said:
can i sharpen d2 with corondum
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You can use corundum, (aluminum oxide), though depending on the grit it may be slow, given how wear resistant D2 can be. I've sharpened D2 on Sharpmaker rods in years past but it is a slow process.

Silicon Carbide (Crystolon) would be quicker to get the initial sharpening done, and might then benefit from finishing on Corundum.

There are many paths, but some are quicker and more efficient than others depending on how thick or thin an edge you are dealing with.

Not much we can do to change the price of sharpening gear in Indonesia, so you'll have to do the best you can with what's available and within your price range.
 
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albert_ilalang said:
can i sharpen d2 with corondum
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Yes. It's aluminum oxide, which is hard enough to work. It'll be slower than using SiC or diamond, especially for heavier grinding; but it can still work. At the finishing end, with corundum (aluminum oxide) stones, you'll probably notice more burring issues as well, because the abrasive doesn't cut the steel quite so easily as will SiC or diamond.

And there's a LOT of variability in corundum/AlOx stones too. Inexpensive oil stones in it may have issues with premature glazing or other slowing down/loss of aggressiveness, in cutting wear-resistant steels like D2. Those will be a LOT slower, if they work at all on D2. Look for reputable brands (Norton, etc) for the better ones. Avoid the real cheap ones ($5 and less); there are a lot of them out there, in aluminum oxide especially.
 
PURPLEDC said:
Sharpening is an art, and those big sharpeners are like trying to paint a masterpiece with a wagner power painter instead of a brush.
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Sharpening is a basic metal machining operation. Metal machining is best done on a machine that guides the cutter (the stone in this case) at a precise angle to create a precise angle.
Ford motor co doesn't hire artists to make their parts and they don't make them while holding them in their hand and eye balling the results (like a painter would).
Your eye glass lens maker doesn't eyeball the lenses while rubbing them hand held on a stone.

The comparison of brush and canvas (no matter how precise or crude the brush) simply doesn't fly.
To sharpen one makes a sharp edge by forming one or two angles that meet at a line (the edge) the best way to do that consistently is with something that can maintain the relation ship of the two plains precisely. Any wobbling about just forms an inferior edge geometry though it might be faster to create that inferior product.

To use the art / painting analogy : I can throw a bucket of paint on a canvas and call it art. It will surely be faster to complete but if I am attempting to make a precise, recognizable, image I will surely fail or do better with a camera.
 
I have no idea what the above post was trying to correlate, nor its reference. Does anyone?

D2 is nothing but it’s martensite matrix and chromium carbides. D2 is a relatively simple steel and is composed of chromium carbides and the surrounding martensite/cementite with a very tiny smattering of vanadium (depending on the D2 source itself). Use a stone that will cut chromium carbides, as they are harder than martensite and cementite for “best results”. AlOx will do the job especially in the coarsest grits to establish the edge itself, (best with “hard” stones in this category). SiC stones will eat it for lunch. So will CBN or diamonds.

That is all there is to it. Besides proper sharpening technique. But as for what D2 needs to be sharpened well.....you certainly don’t need theoretical nonsense.

For best results, a coarse stone of AlOx will cut and establish the edge bevel. To refine the actual edge apex, a SiC stone is plenty hard enough. CBN or diamonds will be that much faster. But for actual sharpening, D2 is a pussy cat.
 
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samuraistuart said:
I have no idea what the above post was trying to correlate, nor its reference. Does anyone?

D2 is nothing but it’s martensite matrix and chromium carbides. D2 is a relatively simple steel and is composed of chromium carbides and the surrounding martensite/cementite with a very tiny smattering of vanadium (depending on the D2 source itself). Use a stone that will cut chromium carbides, as they are harder than martensite and cementite for “best results”. AlOx will do the job especially in the coarsest grits to establish the edge itself, (best with “hard” stones in this category). SiC stones will eat it for lunch. So will CBN or diamonds.

That is all there is to it. Besides proper sharpening technique. But as for what D2 needs to be sharpened well.....you certainly don’t need theoretical nonsense.

For best results, a coarse stone of AlOx will cut and establish the edge bevel. To refine the actual edge apex, a SiC stone is plenty hard enough. CBN or diamonds will be that much faster. But for actual sharpening, D2 is a pussy cat.
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Looks like the issue is living in a part of the globe where access to even the cheapest stones here are not as available or affordable. Indonesia doesnt sound like a fun place if you like to sharpen
 
samuraistuart said:
Corondum is just Aluminum Oxide, which isn't a "fancy" stone. It will sharpen D2, especially in the coarser grits. If I had the option of Crystolon, tho, I would use that instead. It's Silicon Carbide, harder than AlOx.
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Yep.

'Corundum' is (originally) the mineral name for naturally-occuring aluminum oxide, as mined from the earth. The term is used kind of interchangably anymore, whether the stone is made from the 'natural' mineral grit or if it's purely synthetic.

I'm a little leery of the ones labelled as 'corundum', simply because it's a little more vague as to the quality or sourcing of the raw material used in the stone. Such stones can run the whole gamut, from horrible to very good. I cringe at the thought of trying to reprofile a blade in D2 on a cheap stone, even if it is some type of 'corundum'/aluminum oxide. The bad ones glaze much too fast in use, even on simpler steels. I have a couple of those laying around, and they don't do much for heavy grinding anymore, instead diminishing to the minimal aggressiveness of a much finer touchup stone at best, or turning into a burr-inducing monster that seems to bludgeon the blade's edge like thousands of microscopic ball-peen hammers (I have one like this, too).

Synthetic aluminum oxide stones have come a long way in terms of grit shape, size, friability, toughness and uniformity of grit size, all of which can be engineered-to-order into the product and likely would do better than the natural stuff, anymore. That's why I'd always suggest buying from reputable brands, for AlOx stones in particular.
 
I wasn't able to sharpen d2 with anything other than sic or diamonds. Or it was just taking forever and I wasn't doing it long enough. But then again I don't have a course alum ox stone.
 
To hijack, what finish do you leave on your d2? I usually apex with Spyderco ceramics, but didn’t like it on the only d2 blade I own. Could’ve been user error, but it didn’t seem very sharp until I went back and made a toothy apex bevel with dmt F (~600 mesh).
 
samuraistuart said:
Corondum is just Aluminum Oxide, which isn't a "fancy" stone. It will sharpen D2, especially in the coarser grits. If I had the option of Crystolon, tho, I would use that instead. It's Silicon Carbide, harder than AlOx.
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A crystalon isn't a fancy stone either. Go figure
 
Dangerously said:
To hijack, what finish do you leave on your d2? I usually apex with Spyderco ceramics, but didn’t like it on the only d2 blade I own. Could’ve been user error, but it didn’t seem very sharp until I went back and made a toothy apex bevel with dmt F (~600 mesh).
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Diamond has been my preference for D2, at higher finish. Especially in stropping D2 to a higher polish, I've noticed it's more prone to edge-rounding and loses it's bite, if I go too far with AlOx polishing compounds especially. To fix that after the fact, I take it back to DMT EF (sometimes follow that with EEF) and then polish with 3µ diamond paste on a hard substrate (I use basswood for that). Leaves the edge much crisper that way, at high polish.

Edited to add:
I keep remembering D2 has about 1% vanadium content. For most sharpening of D2, it shouldn't matter that much and probably doesn't. But I can't help but wonder if it's that marginal vanadium content making the subtle difference in ease of polishing at the finer end, and why diamond seems to make it much easier there. Just wondering out loud...
 
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Obsessed with Edges said:
Diamond has been my preference for D2, at higher finish. Especially in stropping D2 to a higher polish, I've noticed it's more prone to edge-rounding and loses it's bite, if I go too far with AlOx polishing compounds especially. To fix that after the fact, I take it back to DMT EF (sometimes follow that with EEF) and then polish with 3µ diamond paste on a hard substrate (I use basswood for that). Leaves the edge much crisper that way, at high polish.
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I only have 1µ on basswood, but that’s a good idea. I’ll redo the edge with EF and see if I can jump to the strop.
 
DeadboxHero said:
A crystalon isn't a fancy stone either. Go figure
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Correctamundo. You don’t need fancy stones for D2. All D2 isn’t the same. Some have higher vanadium close to and above 1%, other D2 is lower in V content. Just like David mentioned , not all AlOx stones are the same. Some have harder binders than others. As to if that is better depends on the stone itself.
 
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