The measure of blade sharpness

What criteria do you guys use to call a blade sharper than another?

Let me explain. All the blades I've tried feel almost the same with a few feeling a little better than the others as long as I'm shaving WTG. And basically I can get a decent shave from any of them.

Now switch over to doing an against the grain shave and it's a whole different story.
I used a feather that already had 3 shaves on it and it felt great and left smooth skin as a result.

I used a brand new Astra which I always thought was a nice sharp blade and it pulled and dragged and was pretty uncomfortable.

So when you guys are posting about how sharp a blade is are you counting ATG too or just WTG and XTG?

Edit:
EJ89

I don't know the general measurement of sharpness used on the board. I just wanted to comment on the brand new blade dragging. I don't look forward to the first shave with a new blade, the second or third shaves always seem smoother to me.

I'm with SuperChris on that. For some reason the first shave or two with my fave PermaSharp is less carefree than the four or so that follow. Any insights/observations?

Weird, my third and fourth shaves always seem a lot smoother as well. I thought I was just crazy!

I tend to notice sharpness the most on against the grain vs. with...(comparison of Merkur vs. Feather blades, for example).

I generally judge a blade by my ATG pass because it has the potential for greatest resistance (before), effort (during), and irritation (after). All of the blades glide smoothly for me during WTG or XTG passes. Not all are equal for me ATG.

Also, some blades, for my face, like Derby and Merkur, seem to get better (i.e. smoother, more comfortable) after one or two uses while some, like Astra or Feather, are at their best on their initial use. YMMV, but the first use on a Feather blade is as smooth as I can get on my face.

I agree with the sharpness being most "detectable" while going against the grain, although to me, the sound is also detectable when going with the grain. The more sharp the blade is, the more I seem to hear it cutting. Am I alone on this?!?

As for the first shave with a new blade being less comfortable than the follow-on, I would have to agree. Too bad there isn't a way to "rough-up" the blade when it is out of the package to bypass that 1st shave feel...

tenpin524 said:

As for the first shave with a new blade being less comfortable than the follow-on, I would have to agree. Too bad there isn't a way to "rough-up" the blade when it is out of the package to bypass that 1st shave feel...

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I have read several threads on here that reference "corking" the blade. I am not really sure what the process is, but I guess it just running a cork along the edge of the blade.

Interesting. Need to investigate that.

gegarrenton said:

Weird, my third and fourth shaves always seem a lot smoother as well. I thought I was just crazy!

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Well, you still might be crazy, but your experience is echoed by a lot of other members, myself included.

BlackBard said:

Well, you still might be crazy, but your experience is echoed by a lot of other members, myself included.

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I should edit, I am definitely crazy.

I personally think any blades sharpness is measured in what it can cut.
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I judge blade sharpness based on how deeply they cut me.