Utility Sharp and Shaving Sharp, Which is Best?

[Confederate]

There seems to be a great deal of pride in sharpening a blade to shaving sharp. Someone on another thread said his 440 blade got wickedly sharp when he sharpened it, but very quickly went to "utility sharp."

That's been my experience with 440A, too, and also, I might add, AUS6, AUS8 and others. The very cheap steels made with little or no quality control, won't sharpen much at all, and seem eternally dull. But what of shaving sharp? What is it we want our knives to do?

I've noticed that some blades seem not to be not very sharp to the touch, but they cut paper quickly and with without tearing in a clean, straight sweep. They also cut wood, cardboard and other materials with no problems. Even my ATS-34 blades sharpen to shaving sharp fairly easy, but then tend to lose the extreme edge with a little use and settle down to a good utility sharpness that satisfies all of my needs.

What edge do you prefer and why? Which angles do you want your blades to be comfortable with and how often do you sharpen your EDC? Also, what blade steel and grind works best for your edge requirements?

 

[PetaBread]

When i get my first knife ill answer all of your questions. :foot:

Actually... Ill just prematurely answer the questions.

Plain edge - easy to sharpen, 40 degree angle, and I want it so sharp, it can cut like a laser. :thumbup:

I also like all Super stainless steels(154cm, vg-10, Ats-34, etc...) and Damascus just b/c of the look

 

[msiley]

Here's my opinion and it's just that (stemming from experience and some
understanding of steels).

If your goal is to have a knife stay sharp as long as possible cutting
soft materials then an edge at a steep angle and as sharp as possible will
outlast an edge that is duller and/or and has a more shallow angle.
Given the same steel of course.

With steels that have a high degree of edge stability like the sandviks or
simpler carbon steels then this is when they work best.

On the other hand I find that D2 cuts just as well with a rougher edge
as with a razors edge across many applications. This is most likely
do to the large carbide formation. Not that the razors edge is a bad thing on
D2 but the rough edge (this does not mean a dull edge) has good slicing ability.
Kinda like having micro serrations.

To sum this up a dull edge will get duller faster then a sharper edge.

As far as grinds, for small knives I like thin edges and steep angles.
For larger knives I like a convex grind/edge since the edge is stronger.
For medium sized (4-5") it just depends on what I'm going to use it for.

Personally I like a fine edge on my knives and I like to keep them that way.
So, the 'cheaper' steals like 420HC are fine since I can get them back to
shaving sharp with a few swipes on a piece of leather. Also, 1095 is easy to get
wicked sharp. Whereas, it takes forever to get an edge on D2 just right
and takes more then a few swipes on a strop to get it back to a razors edge.

 

[johnny reb]

I can`t figure it out, So I carry one of each

 

[ginaz]

i've come full circle. i used to favor narrow angles and high levels of polish. then i went through a phase where a medium diamond edge was what i liked. it had a saw-like action that was very grabby. now i'm back to the mirror polish. i haven't found a circumstance yet where a duller knife cut better than a sharper one. webbing, rope, seatbelt etc. it all cuts better with a sharper knife. can i get by with a lesser edge? sure, but why?

 

[hwpaintballer]

What edge do you prefer and why? Which angles do you want your blades to be comfortable with and how often do you sharpen your EDC? Also, what blade steel and grind works best for your edge requirements?

What edge do you prefer and why? I prefer close to shaving sharp.

Which angles do you want your blades to be comfortable with and how often do you sharpen your EDC? As to which angles it really depends on the knife on the original angle that was one it, I usually try no to change it to much. How often I sharpen my EDC, I get bored easy so most days I will put in a movie or play around on the internet while using a small sharpener to sharpen my EDC or another knife close by.

Also, what blade steel and grind works best for your edge requirements? This really depends on the knife. A small key chain knife I would want a stainless full flat. A bushcraft or a chopper I would like a stainless convex or coated blade. For my edc I am happy with CPM-D2, easy to sharpen holds an edge.

 

[spyken]

I like the edges Spyderco and Emerson put on their blades. shaving sharp with lots of "bite". Mirror polish is sharper, but I don't like the "reflective" quality. I test my edges in my own peculiar way - shaving, biting into the nail, clean swipes on paper and my fabric/cloth test (I roll an old t-shirt into a ball, then slice the ball). When the edges are shaving sharp and mirror polished, they will fail this test and "slip", whereas the "grabbier" edges will slice up the fabric ball as it it were slicing into flesh.

still learning how to sharpen well....kitchen knives are ok due to their thin edges but when it comes to folding knives and hunting/thicker knives....I'm a real padawan.

 

[C.S. Graves]

I often use a rough grit to put a toothy edge on a slicer, then a fine grit to get it shaving sharp for some push cutting ability, yet still retaining those micro-serrations. My preferred edge profile for my everday knives is probably thinner than average, since it seems to postpone major reprofiling for longer, makes quick touch-ups easier to do freehand, and gives me a deeper cut in most materials. Reckon I can get away with it cause I use the blades in a careful and deliberate fashion that's unlikely to end up in chips or rolled edges.

 

[hardheart]

the roughest edge I put on a knife that was still capable of shaving arm hair comfortably was with a 60 grit stone. I'm going to use the flat of a 36 grit grinding wheel and see how that works.

My normal edges are polished anywhere from UF Spyderco to 13000 grit waterstone, followed by chromium oxide+0.25 micron diamond on a leather strop.

 

[Vivi]

i haven't found a circumstance yet where a duller knife cut better than a sharper one. webbing, rope, seatbelt etc. it all cuts better with a sharper knife. can i get by with a lesser edge? sure, but why?

That sums it up well.

Honestly it seems kind of sad we even have terms like "utility sharp" or "working sharp" to use as euphemisms in place of saying "I'm lazy" or "I can't sharpen well."

This is a knife forum, after all.

Coarse or polished, 40 degree inclusive or 10 degree inclusive angle, there's no reason your edge can't effortlessly shave arm hair, assuming you're sharpening something properly heat treated.

(I roll an old t-shirt into a ball, then slice the ball). When the edges are shaving sharp and mirror polished, they will fail this test and "slip", whereas the "grabbier" edges will slice up the fabric ball as it it were slicing into flesh.

How polished are you talking? The highest grit I currently have is about 2000 and my edges cut fabric very well at that level of polish, though I know others go much higher.

 

[spyken]

That sums it up well.

Honestly it seems kind of sad we even have terms like "utility sharp" or "working sharp" to use as euphemisms in place of saying "I'm lazy" or "I can't sharpen well."

This is a knife forum, after all.

Coarse or polished, 40 degree inclusive or 10 degree inclusive angle, there's no reason your edge can't effortlessly shave arm hair, assuming you're sharpening something properly heat treated.



How polished are you talking? The highest grit I currently have is about 2000 and my edges cut fabric very well at that level of polish, though I know others go much higher.

probably a combination of highly polished and convexed. it will still cut the fabric, but doesn't bite like an edge fresh of a fine diamond stone (then stropped).

 

[Roger999]

I found a very high polished edge to out perform a toothy at any cutting task that I have needed or encountered, with softer materials I need my edge to zip right through, the hardest material I ever cut is wood.

I also like sharpening my knives, I find it very relaxing and enjoyable to put a high polished edge on a blade. I usually use 10-15degree edge angles for my folding knives and a 20degree angle for SAK's(I am trying a 10degree angle on 1 SAK though).

I touch up my blades with a 6000grit waterstone then a strop loaded with Chromium Oxide when my blades cannot zip through newspaper with ease. I sharpen my edge when I can see reflections on the edge of my blade when I put it under a lamp.

 

[brians]

I like to get mine to push-cutting paper sharp.

 

[donny bee]

Who will be the ones to define what is sharp, and what isnt? How much refinement is required for a inexspensive knife? I do believe a certain amount of skill is what is most important compaired to steels or sharpening equiptment.

 

[Vivi]

probably a combination of highly polished and convexed. it will still cut the fabric, but doesn't bite like an edge fresh of a fine diamond stone (then stropped).

Fine diamond stone is about where I like to stop my sharpening as well. It seems like a good compromise between polished and toothy.

 

[symphonyincminor]

Maybe the question needs to reworded: what kind of materials are you cutting and what sort of edge is best suited for that job?

How thin of an edge do you need to cut packing tape or an envelope? For woodworking? For skinning and gutting?

 

[hardheart]

As thin as possible, how possibly thin is determined by the steel/heat treat when coupled with user action. Vivi has probably provided the best examples of how 'too thin' is not for many cutting tasks.

 

[donny bee]

How thin you can run a blade will be dictated by the quality of the steel, and by what you are doing with it. How long it will stay sharp will depend on the grade of the steel, what you do with it, and how well you can sharpen it.

 

[Vivi]

Maybe the question needs to reworded: what kind of materials are you cutting and what sort of edge is best suited for that job?

How thin of an edge do you need to cut packing tape or an envelope? For woodworking? For skinning and gutting?

I did a little research.

I asked a few times here, and read other threads asking, "What do you use your knife for?" Then I tested various steels and geometries under these uses, to define for myself which geometries match which applications instead of trusting popular opinion.

The most common responses were opening envelopes, opening packages, breaking down cardboard, cutting rope and a little food prep. This is similar to my own uses and the tasks I used to test edge durability. I found that as long as you push straight into the cut and do not load the edge laterally, most tasks can be accomplished with what many users here consider beyond extremely thin geometry (I'm talking 3-6 degrees per side, or 6-12 inclusive, with a more obtuse microbevel).

Go try all of these common knife tasks with a standard box cutter blade. Watch it not once fail or chip out due to how thin it is.

Now compare the geometry of the box cutter blade to many popular knife models, and note that they are often used for the exact same jobs. The reason, as far as I've been able to deduce, that blades are made this way, is because some people think of their knives are pry bars in addition to cutting implements. Personally there are never occasions I find myself in where I find it necessary to pry with my pocket knives, and if I did I'd carry a tool more suitable for the job like a mini pry bar or a Leatherman with beefy screwdriver heads.

The answer, as Hardheart said, is as thin as possible given the steel, heat treat and intended use. If you intend to baton a cheap 420 series chinese made fixed blade, you would go with a thick bevel. If you have a 100$+ knife of a high quality stainless like S30V or ZDP189 and you use the knife for the things I previously listed, like slicing cardboard, you would be better served with going to 6 degrees per side for the edge bevel and adding a 10 degree per side microbevel.

If you think the knife you regularly slice cardboard with my have to see batoning one day (Or any other "hard use"), you can leave it a little thicker for the "versatility," but it will not then be optimized for pure cutting applications.

Box cutters and kitchen knives are typically ground thin for a reason.

You can still cut with a thick edge. You can also drive your car with under inflated tires. The question, though, is why? Especially if you're here, at a knife forum, reading a thread on edge angles. I would expect you, the knife enthusiast, to crave the highest performance from the tools of your interest.

Those looking for a good arm workout need not apply.

 

[symphonyincminor]

A 40 degree inclusive edge will open mail and packages just as quickly and efficiently as a 12 degree inclusive edge. Most folks don't have either the equipment or knowhow to reprofile edges down to extreme degrees. It's time consuming, even with a Lansky or Edge Pro. If all your pocket knife does is cut soft non-abrasive materials, I don't see how thinning the edge down to extremes will net any extra performance for occasional zip tie, string, or envelope.

For kitchen knives, 10-15 degrees inclusive is outstanding (if the steel can take and maintain that sort of edge). All you're cutting is soft vegetables and meat... but the performance gained is worth the time and effort because you're cutting for extended periods of time. A 40 degree edge will work just fine too, but there is a noticeable difference because of the prolonged use.

I guess my point is for duration cutting, a super thin edge is the way to go. For a pocket knife, a super thin edge is great if you have the skills, equipment, or the money (Krein regrind), but it isn't necessary.

Your car analogy is apt: I wouldn't mind driving around the block to the store with deflated tires, but I sure as hell wouldn't want to go on a road trip with them.