Part 2 | Z-Cut VS Victorinox Paring Knife | Spyderco Gauntlet Fine Edge Test

BD1N is back in the Spyderco Z-Cut to endure some tests against the Victorinox paring knife wearing a fine edge from the Spydero Z-Cut!
Also check out my tutorials on dual grit sharpening.
What's a dual grit edge, you may ask?
Think: high performance aggressive knife edge!!! This method for versatile razor sharp knives is fast, easy, and leads to edge retention increases of up to 50% in some tasks! Watch my tutorials to quickly learn innovative hand sharpening techniques with whetstone, diamond plate, & honing strop.
The dual grit method is a specific method for sharpening one side of the edge coarse and the other fine - an updated tutorial is below:
• CPM MagnaCut Dual Grit...
And the results have been observed by independent testing:
• You Won't Believe How ...
If you're curious about the science behind the edge mechanics, check out this scienceofsharp.com article in which Dr. Todd Simpson analyzes the effect:
scienceofsharp.com/2021/06/15...
Please consider supporting me on Patreon if this helps you,
www.patreon.com/thehomeslice?...
Whether your passion is bushcraft knives, survival blades, hunting & fishing knives, edc knives, or kitchen knives - this method could revolutionize the way you sharpen your knives and make your edge last longer!!!
#thehomeslicesharpening #dualgritedge #dualgrittest

[@danielbottner7700]

Re- oval abrasives ~ Your scientific approach & thoughts are always appreciated. They open my mind to relative & important details/mechanism's of what's likely happening to the atomic structure of metal alloys in the cutting edge. I was surprised in my initial testing of hand sharpening methods to see metal smearing at the apex when attempting to refine the cutting edge on news paper. Overheating & destroying the atomic structure of the metal immediately became my main concern. Your conclusions open my mind to other mechanisms & seem spot on. I have thoughts of other forces that also may be at play here. My thoughts gravitate toward the concepts of support provided by the metal in close proximity to the abrasive/contact area, reducing the atomic structure breakdown. Two ways: ( 1 ) Physical support of near by metal limiting distortion: this limits carbon cracking & deterioration of metallic crystal structural bonds . We know some distortion can result in what is known as work hardening which can have it's benefits, anything more is straight up destructive. ( 2 ) Metal in close proximity to the abrasive/contact area provides a heat sink; limiting temperature rise & heat related carbon cracking in the metal supporting the apex & the apex it self.

[@homeslicesharpening]

Oh, that’s super interesting!!! Have you read Todd Simpson’s latest article series on sharpening S110V? It sorta harmonizes with some of your thoughts. He basically finds that high alloy powder steels don’t “stay sharper” but rather “dull better” in the sense that the edge breaks off in very very small bits along grain lines between carbides. The resulting edge has sharp shoulders - we usually refer to this phenomenon as “breaking down from a fine edge to working edge”. He then found that one of the primary reasons for a “super steel” to dull is that during use the apex flexes, and carbides which are touching break apart, opening spaces between them and promoting larger chips. The larger chips then require more force to cut with, and the additional force contributes to the edge “mushrooming” which is often where full dulling occurs. It’s a good read.

[@danielbottner7700]

Have you come up with a theory of why those oval abrasives achieve better results with less effort than the flat stones ? Durability of the cutting edge lends credence to the concept that the atomic structure of the steel left in the cutting edge has endured less damage. The satire to me in crafting high end knives from high quality steels is how the atomic structure of the steel in the cutting edge is often trashed in the sharpening process. The cutting edge is arguably the only portion of the knife blade where high end steels yield a perceive benefit over mid range knife steels. Conceptually I believe the HRC loss is likely higher in high HRC steels. There is research lending credence to the concept of a 5 to 7 HRC loss from sharpening at the theoretical apex in 59-60 HRC SV-30 knife steels. Any thoughts . . . ?

[@homeslicesharpening]

Hey Daniel! Always a fun scientific thought for me haha! Re: Hardness loss - I had not heard that! I know Todd Simpson observed subsurface damage in steels during sharpening in proportion to the size of the abrasives used (IE a 20 micron diameter abrasive might damage the steel 15 microns deep, while a 3 micron strop might only damage 2 microns of steel underneath). I think he was unsure whether this would have a detrimental effect or not, but recommended going through several steps of smaller abrasives and strops to clean this up if you are sharpening a straight razor that needs ultimate stability in a very thin apex. There is also the question of work-hardening. I do wonder whether my dual grit method harnesses this "damage" to subsurface steel in the sense that it relies on moved metal - and metal that has moved often experiences work hardening. This makes it harder to wear away but more brittle. I do feel that it's better to clean up as much damage under the apex surface when you intend to chop, because I think subsurface damage is more of an issue in an impact application. What research are you reading that suggests a loss of hardness? That would be a new perspective for me.

[@homeslicesharpening]

Re: Oval abrasives - I think that they work better because they are rounded. On a flat stone, the pressure you exert is spread out along a flat surface, slowing the abrasive wear by reducing the localized psi, if you will. On an oval you are only ever touching one point on the edge (maybe 2 on a serrated knife), this focused the force and cutting action of the stone to a tiny localized area, increasing speed and efficiency. That is my current theory. In ceramics, the effect is compounded because you are relying on adhesive wear. Which is to say, there are no particles ploughing out microscopic curls of metal as you'd see in conventional abrasives, rather the steel is "micro-welding" itself to the ceramic surface, and the metal could be better described as being "smeared" or "sheared" off. Not only does this have apparent benefits in reducing subsurface damage, but it also means that if the oval shape focuses the force to one point, there is a lot of "grab" to fold a burr over and shear it off - resulting in a clean edge. From my current understanding, that is what I think is going on. Cheers bro!