Thread: Dan's Whetstone True Hard

Originally Posted by Marshal

It all depends on the density of the stone really. Translucents, True Hard, and Black stones all fall into the same density range. I imagine one simply finds more Black stones at the densest end of the spectrum, but my True Hard performs every bit as well as any of my Translucent stones and they all have potential to have the same high density as a Black stone.

Good info! so basically the only difference between the "surgical black" and the "Translucent" (other than the price) is the color of the stone?

Have you been able to check density? I vaguely recall measuring dan's black stone at about 2.65 SG. The trans was about the same.

The true hards may vary a little bit more from stone to stone.

I purchased a "hard" from dans for my IM-313 (for kitchen knives, my wife has gotten into telling all of her friends that we can sharpen their knives for free), and it is dead nuts 2.5 SG and has a bit of bite that has mostly subsided, but it's got little tiny pores on it like you'd expect from not being insanely dense like a good trans or black stone will be. Those pores mean that it will never completely shut down like you can manipulate a good trans or black stone to do, but in my application, that's more than fine (most people have junk knives that can have a bevel reground by hand on a crystolon, cleaned up on a fine india and finished with the dan's hard - i doubt they can even hold an edge good enough for the hard once you strop off the wire).

At any rate, if the true hard is 2.55 SG or something like that, it would easily explain the difference in aggression. As long as the pores are minimal, it can still be made to do just about anything, including totally shutting it down so that it will mostly burnish steel that's in the rc60 range (like razors).

At some point, I will splurge on a true hard from dans, but I just picked a 10x3x1 trans off their specials page and don't want to put another 2 bills down on a true hard at this point. I'd like to get them on the phone at some point and see if I can get something really special out of them, but I can tell that when I start talking to them on the phone, they're not quite ready for it!

Originally Posted by CamMorris

Good info! so basically the only difference between the "surgical black" and the "Translucent" (other than the price) is the color of the stone?

Pretty much. Soft, Hard, True Hard, Translucent, and Black are all some odd %99 Novaculite, a form of silica if I remember right. The difference is the density of the stone. And when we get to the densest part of the spectrum they break it up by color somewhat. True Hard stones are mottled/banded or a hodge podge of color. Translucents are as the name suggests and as homogenous in coloration as they can manage. And Surgical black stones are, of course, black/dark grey.

The person to talk to at Dan's is Steve Kirschman, son of founder Dan Kirschman. He is extremely knowledgeable on all things Novaculite. The ladies, love them all, are not expert. They read the script. Steve was emphatic, and now so am I, there is no difference amongst the True Hard group of Arkansas Novaculite stones, including Hard Black and Translucent. Color is the only difference, which is cosmetic, and makes no functional difference. The magic number is, all the True Hards are 2.5+ gravity.

Thanks LHT-Great to know. May of us just got more and more confused by the various designations, which apparently aren't consistent from decades past and vary a little between companies. I believe Dan's should know more than anybody, and I know you have researched this topic exhaustively, even with that very useful field trip.

Note to self: "THEY'RE ALL THE SAME." Just hone already-I find this clarity comforting as my banded trans and surgical black sit at the ready beside me on the desk for when work gets too much.

What I'm saying is that if you have a stone that's 2.65 and one that's 2.55, there will be a difference in fineness. Maybe not after both stones have been used for a few years, but for a while there will be, and then every time the two are lapped.

The difference between the nortons that I've had has been about a tenth. Just about everything I've run into that is really fine is mid 2.6s. While I know their cutoff line is 2.5, if you get a trans from them and it's 2.68 and you get a true hard and it's 2.55 (which I doubt you'll get, I think they'll give stones above that), there will be a fairly substantial difference in cutting properties.

you won't get a trans stone that's 2.55 SG, though, there would be too many pores in it to block light to be like the dan's trans stones (which are "very translucent").

I have a trans coming today (actually, my wife picked it up. If she doesn't go nuts and throw it in the trash (i hope there's not a receipt with it), then I'll be able to measure it tonight).

Certainly not arguing that you can't have a pure white non-trans stone in the density I mentioned above, but when you get to the point where the trans stones are, very slight changes in density make for a difference in performance.

I did have a pure white with color streaks stone from a seller on ebay a couple of years ago that was in the mid 2.6 range and it was about the same as a trans. The seller sold the stones so cheaply that I believe it was $85 with free shipping, he threw in a cedar box with brass hinges that had several compartments, and put a 2x4 gray translucent stone in the box with the white one. I should've bought everything he had.

I think the statement should be that when the density is the same, the three types have similar qualities. There is a range within the grade, though.

In order to measure the density of these stones correctly, you need calipers and a scale that measures in mg, and then to confirm that the stones are in fact square and the same thickness all around.

Just out of curiosity, I went out to check the density of silica (specific gravity).

...

2.65. (and a follow up look for novaculite shows figures of 2.66 and 2.7). I'm not surprised then that a stone that is almost completely pore free might feel a little bit different than one that is around 5% pores. The pores are what give novaculite stones continued cutting power after the particles have dulled on the surface.

I have measured higher than 2.65 (2.68 or 2.7), but never on a stone that had a regular enough shape that I could say for sure that I'm right (in fact, I'm sure that the odds are way in favor of me not being able to measure the stone in question accurately - which was a natural whetstone black trans that wasn't even thickness, but did have flat planes on it on all sides. They just weren't coplanar).

(I can hone a razor on a pike washita, by the way, so the concern here has nothing to do with honing razors, they should all easily be fine enough with a properly conditioned surface).

Learning a bit here. Thanks for sharing all this info. Question, the soft is not the same as the black or thrans right? Its a different animal?