Thread: Sharpness vs. Harshness.. you decide

So in the passed year that I've been hanging around these parts, there's been an often discussed topic I've been banging around in my head: sharpness (aka "keeness") vs. harshness. I've been trying to wrap my brain around both of these concepts, and here's my take on it, for better or worse...

My definition of "sharpness": the pressure required to pass the blade through the shaft of hair. The less pressure required to pass the blade through any given hair, the "sharper" the blade is.

My definition of "harshness": How jagged the blade is in relation to how sharp it is. Also the perceived amount of irritation. The more jagged the blade, the more irritation, the "harsher" it is. HOWEVER, harshness is also a product of sharpness. When you start getting really sharp, you're gonna start shaving off more skin and getting more irritation, even if the blade has no jaggies at all (impossible, but we're just talking theory here). So it does follow that harshness (to some degree) advances with every level of sharpness, but can be moderated *greatly* by how non-jagged the blade is for it's current level of sharpness. Did that make sense?

Seperating these two out has aided me a ton in honing. I've read in several recent threads about "how can a blade be too sharp??? You're nuts!" And the relevant responses. I'm on the side of, for the most part, a blade can't be too sharp. Well, that's not *entirely* true... some factory blades are too sharp for me. Anyway, I digress....

Let's hash out the infamous HHT for a sec. There are those that adamantly oppose its use, and an equal number that say it izzle the shizzle. Yesterday I posted that I'm in the HHT fan club, but only a, and I quote, "TRULY PASSED" HHT. Emphasis on the "truly passed" part. It's possible to get a phony HHT result. Overly jagged blades (read: harsh blades) can regularly fool people into thinking they have a passing HHT result. The hair can catch on an imperfection and snap in half. *NORMALLY*, the blade will "ping" or make some such sound when the hair breaks. THIS IS NOT A "TRULY PASSED" HHT RESULT! It is the result of a sharp *and/or jagged* blade. A guy around here used to have an animated .gif in his signature that showed a great example of a truly passed HHT. The hair shaft falls silently and swiftly under nothing more than it's own weight upon contacting the blade. No ping, no pop, no dramatics. It just lays over and dies. THAT is a "truly passed" HHT. A blade so sharp (and so smooth) that the blade passes through the shaft with no more pressure than it's own weight. Awesome. Imgagine how lilttle pressure that same blade is gonna require to pass through the whiskers on your face. And as long as the edge has no jaggies on it, it's gonna be smooth doing it.

So how do you check to make sure your blade is not just sharp but smoooooth? Well, of course there's the shave test. But prior to that, there's a truly positive HHT, as well as microscopic observation. Spend 12 bucks at radio shack on their little microscope. Use it to inspect your bevel/edge very closely. You should see zero chips, and it should shine like a mirror (unless you're using a Japanese finishing stone, then it might look hazy), and you should see *zero* scratches at the very edge of the bevel.

Having a sharp and shiny-smooth bevel/edge = a very sharp, not harsh blade that will pass the shave test with flying colors most of the time.

/rant mode off.

Check out Gssixgun's thread from a few days ago: http://straightrazorpalace.com/advan...ller-edge.html

I'm in the "even a perfectly smooth edge can be too sharp" camp. I don't like shaving with an edge than can only barely touch my skin, with the payload of weepers if I don't painstakingly watch shaving angle and pressure.

Nice to see you posting some more, my friend,

Bart.

Well, I've never seen a razor that was too sharp. I've seen razors that were overhoned and were honed to the point the edge was too brittle and just crumbled with use but as they say sharp is sharp.

Some media like .25 diamond will produce a harsher edge however the way I look at it a razor needs to be as sharp as possible. What you need to distinguish is what is sharp and what is overdoing it. But don't ever use that horrible term oversharp or Cletus will come over and hurt you.

I like smooth versus harsh in razors and in just about everything but that thread that Bart linked to covered all of it pretty well. I too am glad to see you back FP.

Thanks, guys... yeah, that thread kinda got me going about the whole too sharp/harsh thing.

Originally Posted by thebigspendur

Well, I've never seen a razor that was too sharp. I've seen razors that were overhoned and were honed to the point the edge was too brittle and just crumbled with use but as they say sharp is sharp.

Some media like .25 diamond will produce a harsher edge however the way I look at it a razor needs to be as sharp as possible. What you need to distinguish is what is sharp and what is overdoing it. But don't ever use that horrible term oversharp or Cletus will come over and hurt you.

Agreed. And lately I've been following .25 diamond paste up with .1 lapping film.

The .1 lapping film does not seem to increase the sharpness at all (as you can probably imagine) but it *does* take away a substantial level of harshness from the .25 paste, which at this level of sharpness does a *ton* to improve perceived harshness, irritation, burn, and the dreaded weepers.

I am a recent convert to .1 micron lapping film, and I love it. It's even put my Japanese finishing stone HAD under control.... for now.

My latest go-to sharpening method, which is producing the smoothest and sharpest blades I've produced so far, is Coticule, .50 Chromium Oxide, .25 diamond paste on leather, .1 lapping film on granite, webbed fabric strop, latigo strop. Examining under a microscope reveals a blinding mirror finish with zero scratches or chips, frog's hair HHT passed, and I have yet to have one not shave anything less than completely comfortable. Previously, I was coming off of .25 diamond paste, and would have to work on the webbed fabric and latigo for quite a while to work out the infamous .25 diamond harshness problem.