[Coiloil37]

Originally Posted by Dean2

So Coiloil37

After deciding to give one of these super knives a try I have been doing a fair amount of research and trying to learn. I have a question. You claim the D2 knives you have from Crotts and Dozier have far superior edge holding capability. I have studied the chart you provided, read a bunch of stuff on Phil Wilson's site as well as other links you and they provided. I fail to understand how D2 steel accomplishes this when all the test results say S30V hold its edge longer at the same hardness. See the chart you provided below which show D2 at 500, S30V at 600 and S90V at nearly 800. What is it about the D2 steel treatment Crotts uses that makes his steel so much better than regular D2. I don't understand how his D2 steel knives would have superior edge holding to a quality s30V knife from a quality maker like Buck knives. Also, if D2 is so great why did you choose to make your last knife out of S90V, which has even higher edge retention scores than S30V. I know there is a good reason, I just don't understand it. Thanks for your help.

That’s a question best suited to a conversation but I’ll attempt to condense some of it into a short(ish) answer. There’s no way I’m going to be able to cover everything

First, no single test explains everything. At best it accurately shows the results produced in that test. Something like this chart above my post is fine, if your out in the woods with those knives cutting sand impregnated cards. It still didn’t explain the exact heat treat for each steel and if it was optimal. It did state the blades were all identical and sharpened the same way and the test was run 3 times per blade. Which is cool but different steels require different blade profiles to perform their best, different thickness behind the edge, different edge finishes etc. A rope cutting test is good if your in the habit of turning long pieces of rope into shorter pieces of rope and he stated in his results what the knife was, the hardness and thickness behind the edge but that doesn’t translate to performance on an animal or anything else. In short, neither test have anything to do with processing animals but they’re good at showing the differences between steels under specific sets of conditions.

I’ve used a lot of steels in a lot of different knives and have my own opinions. I break it down depending on use and I’m conscientious of what I’m holding and what not to do with it.


There is steel choice, which is important but less so then what comes next. Then there is heat treat and the blade geometry. You could have a steel with an attribute you desire (perhaps it’s wear resistance) but if it isn’t heat treated properly it could be outperformed by what should be a lesser steel on paper. All the steel choice does is gives a hypothetical ceiling on performance, it doesn’t immediately give you that performance though. All steel attributes are a trade off where you sacrifice one for another.
Blade grind and primary/secondary bevels make a difference. The thinner the steel at the edge the more efficiently it slices at the expense of strength. That includes the thickness of the stock, the grind and the final sharpening angle. Regardless if the steel isn’t tough enough to maintain the apex it rolls or chips. If it is strong enough to maintain the apex, due to it being thinner it cuts more efficiently and requires less force to cut, which equates to less pressure and subsequently damage at the apex… edge retention goes up. That too is a trade off. Carbon steels on average are much tougher then stainless. You could grind 1095 thinner then S90v and it would be hair whittling sharp (think straight razor) but the S90v ground to an appropriate thickness would still go the distance in edge retention and media cut due to its wear resistance.

You wont find a factory knife ground as thin as some customs. Factory knives are built for the average guy who could do almost anything to it. Benchmade, spyderco, buck etc. don’t need unhappy customers because their knife broke so they leave them thick enough to handle nearly anything… at the expense of slicing ability. I’m a little short on factory knives around here but I’ve got a spyderco south fork in S90v which is a spyderco/Phil Wilson collaboration. Spyderco has said on different forums they ground it thinner then most factory knives to try and emulate the custom but mine measures .020 behind the edge and the Phil Wilson custom southfork measures .006-.008”.

To try and answer some questions. Idk what makes Doziers heat treat different. It is though, from what I’ve read D2 is relatively simple to heat treat compared to some other steels but google it and you’ll find Bobs heat treat is legendary and deemed proprietary. He gets more from that steel then anyone else I’ve heard of.

Some of the performance has to do with his grind and it’s performance on flesh. It’s not a grind I would choose for carving sticks and doing heavy work but for processing animals it’s very good. The D2 he uses isn’t the CPM variety and has relatively large vanadium carbides. I’ve rationalised to myself those large carbides maintain a very aggressively cutting “toothy” edge. Part of the reason they do is the media they’re sharpened on (diamond) cut and shape the carbides. If I sharpened them on a softer stone where the abrasive was softer then the carbides I would expect less performance as the steel matrix around those carbides would be abraded by the stone, the carbides wouldn’t be touched and would either be standing proud and unshaped on the apex to be ripped out while cutting or would be ripped out in the sharpening process as the steel matrix around them is removed. Sharpen them properly, at an angle large enough to leave them supported and let those carbides do their job and the cutting aggression and wear resistance is impressive.

I chose S90v out of pride and hope it will outperform D2. Pride because on paper it’s a “better” steel and not as vanilla as d2. Hope is where the meat and potatoes are. I know the heat treat is nailed down and the performance he provides with d2. I have no idea how well his S90v heat treat is. I do know it’s more corrosion resistant, significantly more wear resistant and not as tough as d2. Given that I’m processing animals and not banging it off bones or hammering it through pelvises I’ll give up some toughness for the potential to have more edge retention. D2 isn’t a stainless but even sitting here 200m from saltwater and 3km from the ocean I have zero corrosion issues on any of my knives. I am aware the salt in the air could be an issue with the d2 but I wouldn’t expect it with the S90v. It’s entirely possible the S90v will be a disappointment once I start using it if his heat treat missed the mark. It’s also possible that the increased wear resistance leads to a longer lasting, hair whittling edge then d2.

Like I said I haven’t used it yet. I’ve been so busy fishing I haven’t bothered to hunt since I moved here. I did get permission on a property so once summers over I’ll start knocking deer down and using it. The red deer rut in April so a few more months and I’ll get it bloody.

I’ve owned/used the southfork and two folders in S90v. I’ve found it chippy for edc in the folders when hitting staples, rocks, steel etc but in a game processing knife I’ve never had a problem with it. Time will tell won’t it.