Blade gap and blade exposure. Which is the driver for aggression?

[Guido75]

So, I have a question mainly on blade gap. Setting aside technique (because I can have an effective shave with just about any razor in my collection).

I was wondering: blade exposure I get. More exposure more blade forward and therefore potentially more blade contact with whiskers. Making the razor more aggressive in feel (even though that’s YMMV territory of course).

But why would blade gap contribute to the effectiveness/aggressiveness? I have razors with almost no blade gap and they are beastly aggressive and/or effective.

For example Wolfman (which I don’t have) started at .95 but we are in the 1.x digits now. What does a higher gap achieve?

Just curious…thanks!

Guido

 

[spacemonkey42]

Exposure is the biggest driver of aggression BY FAR!

Gap can be a small driver of aggression, particularly with a large gap one's skin can bunch up in the gap, causing nicks, but I think it is a small factor. Larger gaps can also help reduce clogging, allow longer whiskers to pop back up after the safety bar, and increase the range of angles that the razor shaves at (exposure does this too and even more strongly).

@dawid has an incredible experiment going, testing individual parameters, here is what they found on gap and it looks like exposure is coming soon.

 

[Guido75]

Exposure is the biggest driver of aggression BY FAR!

Gap can be a small driver of aggression, particularly with a large gap one's skin can bunch up in the gap, causing nicks, but I think it is a small factor. Larger gaps can also help reduce clogging, allow longer whiskers to pop back up after the safety bar, and increase the range of angles that the razor shaves at (exposure does this too and even more strongly).

@dawid has an incredible experiment going, testing individual parameters, here is what they found on gap and it looks like exposure is coming soon.

Thanks! Super cool thread!

 

[JimL911]

Positive exposure, big gap and neutral angle feels more like a straight. Take a Stirling Hyper Aggressive for a spin.

 

[ivan_101]

It is not that simple. There is also the degree of bending. And it is very important. Many users consider Merkur Progress a very aggressive razor even @1. And it has a relatively small exposure. It has serious bending which gives more cutting force to the blade. But here enters the 4th factor. It has notches, that function as scallops and allow for a closer contact of the blade.

And I am not even talking about other factors as clamping, how much of the blade is clamped, where it is clamped.

 

[JoWolf]

So, I have a question mainly on blade gap. Setting aside technique (because I can have an effective shave with just about any razor in my collection).

I was wondering: blade exposure I get. More exposure more blade forward and therefore potentially more blade contact with whiskers. Making the razor more aggressive in feel (even though that’s YMMV territory of course).

But why would blade gap contribute to the effectiveness/aggressiveness? I have razors with almost no blade gap and they are beastly aggressive and/or effective.

For example Wolfman (which I don’t have) started at .95 but we are in the 1.x digits now. What does a higher gap achieve?

Just curious…thanks!

Guido

As you’ve said Guido. Blade exposure is the main driver for efficiency (aggression). Starting out I was strongly influenced by Mike @Esox who said gap allowed too much skin rolling under the blade and contributed to skin irritation. The Fatip Grande probably in the very low gap group of razors. Since I had used the Grande exclusively for over three years. Switching to the Lupo, gap was the only reservation I had about the razor. The gap’s a monster compared to the Grande’s. The improved efficiency and large gap felt like I was shaving with a straight compared to the Grande. As far as whisker length a nine day growth would have the Grande choking up and the Lupo would choke up on an eleven day growth. Shaving weekly neither razor had clogging issues. Both open combs. I had already learned that highest efficiency in all aspects of a wet shave equated to highest skin comfort. Adjusting and to my surprise actually acquiring a softer touch with the Lupo’s higher efficiency. My shaves were closer with elevated skin comfort so in my case a win-win. My opinion would be that a soft touch will improve with a more efficient razor, especially if you’re using a sharper blade. I believe and in my shaving experience gap has little to do with lather or whisker evacuation, although they both have limits as to how much whisker length they can handle. I have very sensitive skin and the larger gap has not given me any skin irritation and has actually improved skin comfort. Once again I don’t think gap has anything to do with it in my case. I have used many variations of strokes on both razors and gap hasn’t made any difference one way or the other. Blade exposure is what drives the efficiency of a razor. Soft touch is what provides skin comfort. Keeping in mind that I exclusively single use a very sharp blade for each and every shave. The photo clearly illustrates the gap difference between the two razors. I love the Grande I learned to shave with it. I would never us it again after using the Lupo. Of course we all have and use many different parameters in our shaves.

 

[Star_Wahl_Clipper_Treker]

Take an Assured razor for a spin, and you'll learn the true meaning of aggressive, as you live on the edge of the dark side of the wet shaving force, as it performs reconstructive surgery.

 

[nav]

All else being equal, larger gap is aggressive for my skin whereas larger exposure gives me higher efficiency.

E.g. blackbird is my favourite razor. small gap, large exposure.

Timeless 95 and Rocca were useless for me!
The larger gaps with small exposure irritated my skin and didn't even give a close shave. Had rough patches everywhere even after 4 passes.

Other factors important for me are; minimal blade reveal beyond the cap, a good amount of blade bend, and a larger blade span (distance from blade edge to safety bar edge).

 

[ButterfaceX]

Do not foget about Slants, they still fall into the DE family.
BFX
other variables that can impact the shave (or the user): Weight, Metal, Balance, Tolerances and Blade used.
BFX
but...
"A good swordsman is more important than a good sword.”

 

[Tanuki]

And I am not even talking about other factors as clamping, how much of the blade is clamped, where it is clamped.

I'm with Ivan, in fact clamping/blade edge rigidity is my first parameter in an aggression discussion. But the aggression I talk about is towards my skin, not toward my stubble.

Helical slants add rigidity to the blade edge, so tagging slant razors as aggressive is a bit slanderous.

Open blades have infinite gap and many millimeters of exposure but nobody talks about SR aggression.

 

[Guido75]

nobody talks about SR aggression

Good point John! Never thought about that, but indeed I never ever see mentions of that in SR posts. Hmm…

 

[Guido75]

But the aggression I talk about is towards my skin, not toward my stubble.

Yes, that might be on me. In usually see people talking about aggression in respect to facial impact. For me aggression is about effectiveness in removing stubble. I should have been more clear about that.

 

[BradWorld]

Interesting thread. There is a close relationship between gap and exposure that contributes to effectiveness. And it’s a sliding scale that changes behavior as one parameter or the other increases, decreases, etc. This is precisely why a Wolfman at 1.15 is super smooth, yet a Timeless Bronze OC at .78 is a fierce aggressive blood thirsty beast. But in my world, efficiency has more to do with razor design and engineering. As @ivan_101 mentioned above, clamping, blade angle, blade bend have much to do with efficiency and effectiveness. That is why I will get a better shave from a modern highly engineered razor machined from premium metals every single time versus a vintage razor.

However, for me, exposure contributes more to the blade feel than it does with efficiency. An aggressive razor isn’t always efficient. Sometimes it just irritates my face and doesn’t give me any better shave results than a milder razor.

Similarly, there is a limitation to effective blade gap for me as well. Once I exceed that limit, I get a more harsh face feel, but negligible improvement in shave results, or none. For this example I will go back to Wolfman. I started with a 1.15 WR2 and got the best shaves of my life up to that point. But due to my beard’s swirling and flat-growing nature, bbs results were still challenging. So I went to a 1.25 to see if increase in gap would improve shave results. The improvements were minimal if any, yet the shave was markedly less smooth. So I took the advise of my peers and went for the 1.55 next. Granted the 1.55 was much less aggressive than one would have thought. But it again offered only minimal improvements in shave results. The risk of blood and irritation were far greater. In the end I should have stayed with my original 1.15 and stopped there. Sold the 1.25 and 1.55. Still have the 1.15 at the top of my rotation.

So I think gap and exposure have a codependent relationship. And there is a sweet spot for each. When you find that perfect balance, shaving nirvana can be achieved.

 

[spacemonkey42]

Yes, that might be on me. In usually see people talking about aggression in respect to facial impact.

I agree, the term aggression is usually about how likely a razor will bite, nick, or otherwise rough up one's skin.

For me aggression is about effectiveness in removing stubble.

Effectiveness in removing stubble is usually called efficiency.

 

[Guido75]

Effectiveness in removing stubble is usually called efficiency.

Thanks - efficiency for me is how long it takes to get to BBS levels. So more about duration than result perhaps.

so there’s YMMV in terminology as well. Luckily we are among likeminded, because outside of B&B this conversation is a one way ticket to the ward!

 

[lancre]

IMO, exposure is the main driver of aggressiveness in a razor/blade combo. That's what determines how likely a razor is to bite me. Then the gap determines how big a bite it will take.

 

[Jay21]

My hair lies flat on my skin. For me, blade exposure is an important variable for how well it cuts the hair. Larger gaps work better for me, but at equal gaps, positive exposure shaves better than neutral or negative exposure.

 

[Cal]

Talking about GAP only (in simple terms), it makes a lot of difference if you're a steep angle shaver and no difference whatever if you're a shallow angle shaver.

Just my two cents.

 

[Gecko45]

It is not that simple. There is also the degree of bending. And it is very important. Many users consider Merkur Progress a very aggressive razor even @1. And it has a relatively small exposure. It has serious bending which gives more cutting force to the blade. But here enters the 4th factor. It has notches, that function as scallops and allow for a closer contact of the blade.

And I am not even talking about other factors as clamping, how much of the blade is clamped, where it is clamped.

on the shaving room, the progress is considered a MILD razor..

But tis a massive impact on shape of head, the whole clamping angle.

Once read how the painted gillette flare tips equaled the fatboy on certain settings. They dont match MY fatboy.

 

[Goblin]

I agree, the term aggression is usually about how likely a razor will bite, nick, or otherwise rough up one's skin.



Effectiveness in removing stubble is usually called efficiency.

I have said before that for me Efficiency = Whisker Removing Effectiveness / Negative Blade Feel Effects

You might have a razor that annihilates whiskers like a pair of motorised garden shears, but if it is uncomfortable and unruly whilst doing it (scraping, chattering, biting, etc.) then I don't call that efficient. If we consider the actual definition of efficiency, this razor is directing some of the "work" imparted by the shaving strokes into things I don't want.

Conversely, you could have a razor that doesn't smash the stubble quite as effectively, but still delivers very close shaves in minimal passes whilst being easier on the face and more intuitive to handle. I would consider the second razor more efficient than the first.