The Sharpening Thread

I'd be happy to. I'm a fan of working with the SR101 steel. Does the 311 have a distal taper on it? The ASH-1 I did was near uniform thickness from handle to tip.

 

Not much of a distal taper on it. I know this will make the edge near the tip seem wider than the rest of the blade, due to the thickness at the tip. I don't mind that at all as long as the edge bevel is consistent from side to side!

 

This is good news. I've been using diamonds for over 20 years now and just don't know how I would feel going back to a traditional stone! Talk me in to it Ben!

 

I suppose that's what you get when the intended purpose is hammering it through cement blocks.

 

I also though about sending it out to Josh at Razor's Edge to get the primary grind thinned out with a distal taper towards the tip. That guy is amazing at regrinds!

But I also want to check out what a KME system can do!

 

If this goes down, I'll have to send two packages. If I had the time I would have to see what taking it to a super fine polish and then hitting it with a 1200 grit would do for performance.

 

I plan on sending something over to Josh for a dual hollow grind

Gotta see if I actually like the knife itself when I get it and if I plan on keeping it. That's the hardest part about knife ownership lol.

 

Some S30V goodness. 18 DPS convex freehand. Some tough stuff, but not the easiest to sharpen. Still struggling to take pictures good enough to show the flawless finish. Gives a smooth comfortable shave and will cut hairs .5" from the skin without support.

 

Looks good @Slade! I changed my mind on the 311. It's real sharp now and I don't think I'm going to take it down any thinner. I'm going to send you cts-204p for a 15dps mirror polish instead!

 

CTS-204p and its brethren take an awesome polish. The above is a 18 DPS convex freehand.

 

Where do you usually stop? I have heard a lot of preference for the 1200 range. And also, how do you remove the burr without removing the projecting "teeth?"

And I'm always curious what tasks people find a less refined edge better suited for. I suppose its possible that I am generally doing different things with most of my knives. There is definitely more time spent on creating the convex bevel shape at course grit than there is polishing it, so time wise they are very similar for me. In the KME, polishing adds considerable time.

 

I like finishing with 1200 grit.

 

This has been my experience as well. Coarse, less refined edges seem to cut much better on draw and slice cuts when polished passes through material with less drag when push cutting. I used to like finishing with a DMT 600 grit edge and stropping afterwards. Nowadays, I finish with the DMT 1200 grit edge and only take a few swipes on a bare strop.

 

Yeah, you're right, poor choice of words on my part...but you know what I meant.

 

Ah yes, getting into what makes sharp. this is always fun. Let's try to keep it civil. I don't mean any offense. I am very scientifically minded and like to discuss these things with those who are willing. I am also a bit biased as a result of my own thoughts on the subject, but I am never unswayable by evidence with theory to support it. Some thoughts

Disregarding the scratch pattern on anything but the final bevel, because unlike the angle (thickness) of the wedge of metal behind the cutting edge, it has little effect on the action of the leading edge, during sharpening a simple single bevel edge, the scratch pattern continues all the way to the apex of the edge. Notice that I say a simple single bevel edge referring to the final bevel receiving the scratch pattern and not a multi-faceted or back/micro bevel edge where the leading bevel becomes a fine polished final bevel. A course scratch pattern will leave the same scratches in the apex that they leave in the entire final bevel. This scratch pattern in the final bevel form what get referred to as "teeth" in that they are less supported projections of the apex where the two planes meet. This allows them to form a micro-saw if you will as the single line where the two planes meet is not uniform/straight. the edge angle should be the exact same but not necessarily in a straight line since the scratch pattern will terminate in different places. Since the grits on either side can terminate in various places, they woin't always line up and you will end up with "teeth" that are only half as thick as a finer finished edge of the same angle. They may be slightly sharper initially as a result, but they are also now half as thick and therefore less durable. Might the edge behind these teeth still cut well after the projected teeth are removed? I think so, and this is where continued sawing/sliding effectiveness comes in. After all, the edge was initially nearly the same thickness even behind the "teeth."

A thesaurus will give you polished as a synonym for refined and course as an antonym. The very definition of refinement is 'not course'.

Soft items that deform easily but also have surface tension benefit from this sawing/slicing action as the uneven leading edge applies more psi and breaks this surface tension. The only example I can think of right now are tomatoes. Hard but flexible items such as most plastics tend to resist shearing as a result of their plasticity e.g. plastic zip-tie. We are adding higher friction as a result of a more uneven surface of a micro-jagged edge causing the plastic to be removed as each small tooth takes a tiny bite out of the plastic as opposed to a refined edge taking much smaller bites, or even gliding on the surface without enough pressure, meaning more work required. I will allow that the pressure required for me to cut zip ties with a refined edge is likely detrimental to metals susceptible to rolling which is also a form of plasticity. For me this is such a small fraction of my use that I accept that it doesn't justify a change.

With exception to these two rare circumstances, I'm wondering what else I am missing that benefits from a "toothy" edge. The scythe is another good example, but this is certainly not a common use for any of my knives and even a machete is not used in a sliding motion, nor is a lawnmower blade. You could argue that machetes and axes function by force and the structure of the edge becomes less important than the angle, but the refined edge will still be less subject to deformation by way of support structure at the same angle.

I have a 11 dps convex Shun kitchen knife I use at home in my kitchen daily. I literally have not sharpened it or even honed it in months. The only food items it doesn't meet are hard frozen items, and hard bread. I peel tomatoes with it freehand, knife in one hand, tomato in the other, both hands in the air. After the initial slice to break the surface tension, the thin skin of the tomato is sliced through easily even by a 12,000 ANSI grit edge. For hard bread, a course edge may be slightly better than a refined edge, but the wavy edge of a bread knife is far better than either. I slice cut meat with no issue and never more than a single stroke. I cut stacks of 13/15 bacon approximately 1-1.5" square multiple times this weekend with less than half the length of the 7" kitchen knife described here. I'm thinking that a pushcut makes the length of cut possible theoretically infinite while a toothy edge not capable of pushcuts can only perform for the length of its teeth combined with each stroke.

Is there an instance where a true serrated edge made up of sturdy large scale visible teeth with a refined edge loses out to a "toothy" edge? Same capability of breaking surface tension via the same or even more psi at the tips of the teeth and a largely protected cutting surface.