Question regarding sharpening and edge retention.

[Chapp]

Usually, the softer a steel is, the easier it is to sharpen. From what I understand, the trade-off is that the steel won't keep an edge for a long time. Case in point, 1095. Easy to sharpen, but averadge edge retention.

The thing I wonder is the ratio ease of sharpening/edge holding. Most people often want steel that keep an edge for a long time, even if it means being harder to sharpen, but is the trade off always linear ?

Like say I bump the ease of sharpening by 2 points, do I decrease the edge holding by 2 points at the same time ? Or is steel dependant and each have their own ratio trade-off ?

For example, let's say S30V keep an edge for twice as long as 1095, would that make S30V twice as hard to sharpen than 1095 ?

It's a question I've been wondering for a long time, I'm far from being an expert on steel.

 

[Larrin]

Softer steel is less wear resistant so removing material takes a bit less time. However, harder steels tend to take an edge easier and deburr easier. So no, there is nothing linear about it.

 

[ktataragasi]

I think the answer is like so many other things. It depends.

I feel like it really depends on the blade steel you are talking about. I have read so many posts about Maxemet being so difficult to sharpen but it was just as easy as any other steel I have been working with (s30v, s35vn, 20cv) but holds a crazy edge for a long time. It also depends on what you sharpen on. If you have diamonds it doesn't really matter that much, some may just take longer. Also some steels get a really stubborn burr and some are easy.

Also some of these really hard steels strop back almost as well as the softer steels so in top of a lo get lasting edge you can snap prolong how long you go between actually sharpening.

 

[Chapp]

bump

 

[Dangerously]

Not only is it not linear, you’re missing a whole wad of variables. It’s way more complex than that. There are websites like “science of sharp” or “towards 0.1 micron” that have interesting experiments on sharpening, sharpness, edge retention, edge stability, cutting ability, etc.

For example, edge angle affects retention (acute is better) unless it’s too thin for the matrix to support large carbides, so it differs by steel and heat treat. And that’s only true if the work performed doesn’t have too much lateral force, in which you’ll get more retention with a less acute edge.

No one has the complete model.

 

[GIRLYmann]

fully agree that one has gotta take in to account that there are bound to variables in knife usage.
knife tasking and the material its cutting or used upon plays a significant role in wear.
hard to judge if one doen't methodically log and record details of every single usage
so we could agree in part that high hardness
doesn't necessarily mean one gets away
from sharpening task any lesser if its been put up against some pretty densed material?
just my 2 cents.

 

[Steely_Gunz]

There is also a fair amount of voodoo as well. The mathematical quantifiable level of "sharp" doesn't mean squat if your skill only allows you to get it that sharp using a series of bench mounted stones if you are stuck in the mud lost on day 5 of a 3 hour hiking trip.

For me, edc knives can use higher end steel for lower maintenance but I prefer simpler steel for hard use.

However like others have said, there are so many variables when it comes to sharpening. It is next to impossible to be linear. Sharpening and steel choice is more like a Choose Your Own Adventure than a straight road map.

 

[Chapp]

If It depends on so many variables, why are a lot of people obsessed with the steel they use ? Like you see people being overly happy that a knife use M390 over a simple S30V ?

 

[Mikel_24]

Also worth mentioning that if you use diamond based abrasives for sharpening... there is not such a thing as too-hard-to-sharpen steel. IMHO.

Mikel

 

[Sonnydaze]

I often use a 6" diamond stone, coarse grit, that puts a nice coarse edge on any steel
I'm carrying....beginning to learn effective use of a strop...thanx to Makael...

 

[Silvanus]

If It depends on so many variables, why are a lot of people obsessed with the steel they use

Because new steels are trendy to have. I’ve said it before, the majority of knife users (that includes most enthusiasts) will not be able to tell the difference between 5Cr15MoV and Maxamet. Look at how many knives in the exchange are listed as “carried but never cut anything”, “only out of the box for pictures then put in the safe”, or “only opened an Amazon package and sliced some paper”. Not many knives with high end steels are seeing real EDC use, much less legitimate hard use.

As far as the answer to your question, Dangerously above probably has the best one. There are so many factors that go into a steels edge retention it’s hard to keep up.