Good points. I have a couple of Sharpmakers scattered around, and that's what I use ordinarily. I like to keep my knives arm-hair shaving sharp. It's easy to do with that system and that's sharp enough to do whatever I need.

I also have a couple of the little 3" triangle ceramic rod sharpeners I keep in my earthquake bags. They'll do the job in an emergency. Sharp enough to cut what needs cutting is sharp enough.

Kevin B.

I would take it from the other end of the question:
Is it possible for a knife to be too sharp?

My answer is: No.

The practical minimum of sharpness is simple functionalism: Sharp enough to cut what I need to cut without having to spend too much time or effort.

The practical top end is: How much time and effort are you willing to invest into sharpening and/or maintaining an edge on your knives?

That depends. If I sharpened one of my larger fixed blades down to a very acute edge (like a straight razor) it would do fine with shaving, slicing paper, ect. However, the first time I use it to chop/baton or do any other hard use, the edge would become useless. Probably broken, bent, or heavily chipped. How sharp a tool needs to be depends on the application and what the design/materials can take.

"I've never found the need to shave my arms in a survival or normal outdoor activity"

Spotting that someone else has can be useful! In one of Patricia Cornwalls novels her heroine warns a scumbag in a bar that the he'll never make it to his knife, because cops carry guns....

The Sock

I think I've read that scene. Although maybe it was used by another author as well. Just goes to show, if you're a bad guy...wear long sleeve shirts.

When the blade glides through the target like a bird through air, then it is sharp enough.

My favorite test is if I can push it through really thin paper (thin like a cash register receipt) at 90 degrees without slicing and without having to hold both sides of the paper taught. However I only test my pocket and kitchen paring knives this way. My other kitchen knives are designed to slice so I test them by slicing something heavy like several layers of heavy paper.

i wouldn't bet a penny on it me having quoted even the right author. i only read a chapter. but think it was the first of her books about the female pathologist.
The Sock

Most of my field knives are Bark River Knife & Tool semi-custom knives with a convexed edge. I can easily get them sharp enough to shave hair, and they will baton and still be hair shaving sharp.
A leather strop, mouse pad with leather, or some very fine grit sandpaper all that is usually needed to keep the convexed edge as they should be.

I think your confusing sharpness with the angle, and grind profile, which the blade is configured to.

Edges exposed to more impact and used on harder and tougher materials are usually better sharpened at a more obtuse angle and the grind will typically be one which better supports the edge more.

A straight razor is sharpened at a fairly sharp angle and the grind is often 'hollow ground'. The angle means the edge slices the hair with little resistance and the grind keeps the supporting metal behind the edge out of the way of the cut to reduce friction. A hollow ground blade also sharpens more quickly because you have to remove less metal to reform the cutting edge.

The down side of a hollow grind is that the edge is very much sitting out there on its own unsupported and unprotected from lateral forces or impacts when contemplated in cross-section. Straight razors are rather delicate. So much so that simply dropping one in the sink can break off chunks of the edge and require the razor to be reground at the factory. It is hard to find people who know how to regrind and retune straight razors so the cost and shipping can be prohibitive. Dropping or otherwise abusing these units can mean you need to buy a new one. Not very cheap if you buy quality.

A meat cleaver would be ground to much less of a fine angle and usually to an 'axe' grind that effectively surrounds and supports the edge as it absorbs the stress of impact into hard materials.

Neither the angle nor the grind define how sharp a blade is. Sharpness being how mathematically precise and smoothly the angle of the edge is closed.

A knife used to split wood by being hammered on or otherwise being used roughly in tough materials would benefit from a more obtuse edge and a more supportive and impact resistant grind. If your going to use it like a splitting maul it would be best if the grind and sharpening angle more resembled a splitting maul or axe than a straight razor. Once the blade is well configured it would be better if the edge was appropriately sharp. A different issue.