The Importance of a Rigid Blade (or not)

[BigJ]

Interesting discussion!

My favored razor (Wolfman WR1) is a very rigid design. But, I can also get fine shaves with much less rigid designs so long as I have a fine prep and a slick lather.

For me it is all about technique!!

 

[DaveHStone]

The R41 is an interesting razor for testing the rigidity hypothesis. If I shave at a shallow angle with the R41, it tugs my beards so badly that my eyes water. I've never used a razor that tugs worse than an R41. This is true even with a brand new Feather. I don't get cuts or nicks typically, but it's a very painful shave. Increasing the angle as steep as it can possibly go helps, but there is still tugging going on. The Fatip Piccolo is nearly as efficient, but never tugs regardless of the shaving angle. I'm not alone in this experience. If you search for "R41 tugging", you'll see an awful lot of people complaining of tugging problems. Here are some selected comments from different people:

This is well worn ground, but looking the design of the two razor heads is illuminating. It makes sense that the R41 is less rigid than the Piccolo. I once put together a simple model that scored razors based on Edge to Cap Distance, Edge to Baseplate Distance, and Blade Bend Radius. These are the 3 parameters that I believe most influence rigidity. I didn't have an R41 at the time, but it would have scored below the Ming Shi Futur on these 3 parameters. It's bend radius is 21.78mm (it's nearly flat!), and it's effective edge to baseplate distance is 4.75mm because the blade doesn't actually touch the comb. What does this prove? Absolutely nothing. It was a dumb model. . I still say the R41 tugs my beard because it isn't rigid enough.

R41 has both wide blade gap and large blade exposure.

You don't have to be Einstein to figure out there'll be blade chatter with that geometry.

BTW, it was my first DE razor, by pure coincidence, as back then I had no clue about anything related to wet-shaving. When I think about it in retrospect, I am glad it turned out that way, as after mastering the R41 I feel I can shave with pretty much anything and get a decent shave. As always YMMV.

 

[SCh5]

BTW, the Muhle R41 has a blade gap
that ranges from 0.28 mm up to
0.31 mm .It’s a cast razor ,precision
is not to be expected .Not a large gap actually ,but rather small.Thus ,the
R41 has a very narrow ”angle of attack” range.

Blade exposure ranges from 0.30mm
up to 0.32 ,which is a rather large figure.Blade edge is protruding 1/3 of
a millimeter beyond the shaving plane.
Theoretically ,it can inflict serious wounds ,under poor technique.

R41 is indeed a terrible razor going ATG on low emerging angle stubble
and things really worsen if stubble
is thick and /or coarse .

In wet shaving everything obeys
to the YMMV thing.

I may consider the R41 the most
useless razor ever made.
Unnecessary violent and non-forgiving.
With extreme blade chatter issues and
with zero precision.
Meanwhile other people have found it
to be their best shaving tool ever.

 

[thombrogan]

@Dovo1695 - that’s a whole lot of thought and research in your post and even without my being able to make heads or tails of your second chart and its rating system, there is a lot of data presented to make an argument that a rigidly held, removable blade will usually tug less when cutting ATG than a blade allowed to flex and relax during the same task.

Anecdote versus anecdote, it appears that you were able to partially dampen that flex and release pattern of your R41 by using a more steeply angled position and doing the same with my Fatip Grande made me think everypony praising its rigidity had all escaped from Crazy Town Junction (yes, it’s kind of rigid if one rides the cap, but then the enjoyment of its roller-like comb is lost).

Could my stupid whiskers be less coarse, less curly, less dense, and less ductile than the multitudes experiencing harbor cruises to the Isle of Tugsley with their Mühle R41 safety razors? You had a lot of smart and skillful people in your list of tugsayers, so it couldn’t be anything I’ve intentionally done right with that razor. A neutral angle, the modern WTG/XTG/ATG pass sequence, and chipmunk bites and it acts like it likes me.

Would you please explain the second chart to me some more? A lot of work is collected there and I don’t like my inability to comprehend it.

 

[Dovo1695]

Would you please explain the second chart to me some more? A lot of work is collected there and I don’t like my inability to comprehend it.

It's not really worth thinking about, I promise you. The table shown is just a thought experiment on how one might create a predictive model of the razor "rigidity" based on 3 parameters. It's a rough stab at a conceptual framework, not a finished product.

Further muddling the water, it doesn't use what came to be "standard" terminology. What I called "edge-to-cap" distance is what's shown in the diagram below as "free end distance". What I called "edge-to-baseplate" distance is shown in the diagram below as "clamp distance". What I'm calling "bend radius" isn't pictured in the diagram below, but it refers to how much the razor blade is bent into an "arch" shape by the cap and baseplate. The more curved it is, the more it has become spring under tension, and the more it resists deflection/vibration. The second pic shows what I'm talking about by "bend radius", the third pic shows the measuring methodology. It's comparing the actually width of the blade when flat compared to the actual width of the blade when bent into an arch (typically 22m with slight variation between individual blades).

All three measurements are relatively easy to take with a digital caliper. I just took a subset of razors already in my possession to see if there was any rhyme or reason to it all. Razors X1 - X7 were purely hypothetical razors that defined the probable range of possible razors based on known measurements of existing razors. X1 was meant to be ideal, and X7 was meant to be the worst possible razor. The scores are just a "first draft" attempt done purely as a thought experiment on how one might construct such a model.

If you ever want to read a 150 pages pondering the meaning of "rigidity", whether or not it actually exists, and devising experiments to understand it better, here is the seminal text.

The Great Rigid Blade Experiment

Just kidding about it being "great". It started early this week. I've been using my Rockwell 6S almost all the time lately, couldn't tell you why. I've also honed my lather building skills and can now get really nice, slick lather consistently that really works for me. In reading about all...

www.badgerandblade.com

 

[Dovo1695]

Like anything else, when trying to understand something, a reducto ad absurdum is often useful. Razor rigidity is no exception. The YouTube video below shows an example of the least rigid razor possible. It's a Feather blade mounted on a carriage bolt with two nuts holding it in place. It has a 11mm free end distance, an 11mm clamp distance, and it has no curve whatsoever. Can you shave with it? Of course you can. Is it rigid? If you assume those 3 parameters are important, then probably not. Skip right to the 2 minute mark and listen to the glorious sound it makes. Turn the sound all the way up to fully appreciate it.

I made a version of that razor by replacing the baseplate of my beloved RR Teck II with pair of washers. It rattled like a springless carriage on a dirt road. It's the only razor I dislike more than my R41.

I did a shave report for it as post #520 of the Great Rigid Blade Experiment (direct linked below) . Much can be learned about rigidity with a very simple and inexpensive mod like this.

The Great Rigid Blade Experiment

@AimlessWanderer I'll be the first to acknowledge that I'm out of my depth in the present debate about whether or not the forces that occur during normal shaving sometimes push the blade away from top cap, towards the blade gap. My understanding is that you say it cannot. I've tried to follow...

www.badgerandblade.com

 

[Medivh]

From what I can see from the video, I don't think he's enjoying that shave at all. I could shave with pretty much any DE razor even if it's the worst razor ever made with the worst blade chatter on the universe, but that doesn't mean that I would enjoy the shave or that I would keep shaving with that razor forever. Some folks even talk about ''technique'' like it takes eons of preparations, practice and meditation to fully master it and only a handful of jedi masters can do it or something like that. Shaving in general is no rocket science and even a total noob can master to some degree a straight razor after a few months of constant shaving with it, which is concidered to be the ''hardest'' form of shaving not counting shaving with a broken glass, machete, katana, shank, lightsaber, spoon, axe etc.

Also, just because some razors are loud when they cut the whiskers, that doesn't mean that all of them have blade chatter. Just because something works for one person or a group of people it doesn't mean that it would work for every else and if it doesn't then it's their fault, because their technique or skill is bad. I find that argument absurd.

 

[Dovo1695]

Also, just because some razors are loud when they cut the whiskers, that doesn't mean that all of them have blade chatter. Just because something works for one person or a group of people it doesn't mean that it would work for every else and if it doesn't then it's their fault, because their technique or skill is bad. I find that argument absurd.

I agree with you 100%. I guess I didn't frame that particularly well. It was literally a reducto ad absurdum argument. The question in the post title is "Is rigidity important?". The reducto ad absurdum argument is "if rigidity is totally unimportant, what does that look like, and is it comfortable?". The least rigid razor possible is the one in the video, and although it's clearly possible to get a good shave with one, it isn't particularly comfortable or enjoyable. Somewhere between a razor on a stick and a Wolfman lies an acceptable range of rigidity for 99.99% of people.

For some people that range is very broad, and for some people a bit more narrow and skewed towards rigidity. Some people do not experience tugging with any razor, and some people are more sensitive to it. If you fall into the category of people who experience tugging during shaving, I think a rigid razor can help alleviate that. No jedi skills necessary. It's definitely not one size fits all though. Like everything else in shaving, the relative importance of rigidity is subject to the law of YMMV.

 

[Dualist]

I think blade rigidity is extremely important. My second favorite blade is a Kai, which you can feel is stiffer than others simply by bending it. It's not thicker, but being twice tempered is stiffer.

They do that for a reason. The reason, in my opinion, is for better shaves.

My favorite blade, treet black beauty, is more flexible, to my chagrin. But it performs better in my FOCS. As do all my other blades. I believe this is because of the tension the blade is held in with the twist/slant head.

But I think more important than stiffness is actual thickness or mass. I think that is why straights shave better than DE blades. For me wedges shave best of all, the proverbial squeegie. I think the mass of steel fortifies the edge. As if the quality of the edge partially depends upon the overall mass to a point. Stiffer. My wedges have needed less maintenence. A thinner straight "singing blade" skips over my whiskers, requires a little more work, and definitely calls for more upkeep. It's more brittle. The auditory feedback is miraculous, but I definitely prefer wedges because their performance is noticeably better to me. Interconnected molecules or something. Something backing up the edge and fortifying it.

I dunno. Something almost esoteric but I believe it. And it's more than just weight and momentum, up to a point.

There are plenty of other variables though so my little theories could easily wilt in the face of science.

But I'm intrigued enough to have bought a Wedge blade SE, a Wilkinson Empire. I already have the stones to maintain it and I want to know if the added mass behind the edge, a mini straight in a stick, will have the effects I suspect and/or hope it will have to either prove or disprove my little idea. And give great shaves, maybe almost straight shaves, in a compact and convenient package.

 

[thombrogan]

What I called "edge-to-cap" distance is what's shown in the diagram below as "free end distance". What I called "edge-to-baseplate" distance is shown in the diagram below as "clamp distance". What I'm calling "bend radius" isn't pictured in the diagram below, but it refers to how much the razor blade is bent into an "arch" shape by the cap and baseplate. The more curved it is, the more it has become spring under tension, and the more it resists deflection/vibration.

That non-helical twist adds some rigidity, but I have four DE razors that provide a pronounced bend to the blade:

Maggards V3A - it’s like an R41/R89 in the baseplate with a very round, bendy cap. Shaves alright, but not rigid.

RazoRock BBS - lots of bend, lots of baseplate support. Fairly rigid especially when steep instead of shallow (though underatedly efficient used shallow).

PAA el Fantasma - lots of bend and baseplate support. Not as rigid as expected. Can be generous handing out weepers on ATG pass if one isn’t careful.

Ikon X3 - lots of curve, but less baseplate support than something a RazoRock Mamba (based on pretty pictures, not in person experience) and it’s DE Rigidity Royalty. Somehow smoother ATG than the RazoRock BBS even though the narrow baseplate suggested to me the blade would flex/unflex like a mousetrap.

The second pic shows what I'm talking about by "bend radius", the third pic shows the measuring methodology. It's comparing the actually width of the blade when flat compared to the actual width of the blade when bent into an arch

That may explain why some razors look utterly flappy, but have user reports of smooth ATG passes.

If you ever want to read a 150 pages pondering the meaning of "rigidity", whether or not it actually exists, and devising experiments to understand it better, here is the seminal text.

Thanks. I read lots of it last year on my ill-fated quest to understand things. From that fledgling attempt to comprehend, I nabbed me a FaTip Grande and found it didn’t do steep ATG the way I wanted and certainly stopped being rigid due to the blade exposure and angles of resistance. Used shallow, it’s much nicer, but that comb no longer pampers my skin that way. Small price for a furlough from Scraped Face City, of course.

I did a shave report for it as post #520 of the Great Rigid Blade Experiment (direct linked below) . Much can be learned about rigidity with a very simple and inexpensive mod like this.

Very harrowing. Looks like the type of razor that likes Kardashian-shallow, gossamer light WTG strokes and nothing else.

It's the only razor I dislike more than my R41

I’ve read that the lemon was man-made creation (from breeding sour oranges with citron fruits) meaning that we had to make lemons ourselves before life gave them to us.

It sounds like your dislike for the R41 was so strong that you and your washer baseplate channeled the spirits of ancient, Transoxanian arborists (as one does).

 

[DaveHStone]

Fellows, if you want a smooth, no nonsense, easy to achieve BBS shave, I wholeheartedly suggest you switch to SE razor.

It's important to make a distinction between primary and secondary rigidity.

Primary is the rigidity of the blade itself. DE blades being thin and flimsy are not rigid. Therefore, the secondary rigidity is important when it comes to DE razors; and that's how rigidlly/firmly the blade is held between the base plate and the top cap.

That secondary rigidity is what actually matters with DE razors.

With SE razors, the secondary rigidity is not that important as blades are already rigid. Their primary rigidity comes from much larger thickness, hence SE blades don't bend at all, be it GEM, injector or AC format.

TL;DR get the Vector and a pack of Feather AC blades. BBS every time. No irritation.

 

[Eben Stone]

...If I shave at a shallow angle with the R41, it tugs my beards so badly that my eyes water. I've never used a razor that tugs worse than an R41. This is true even with a brand new Feather. I don't get cuts or nicks typically, but it's a very painful shave. Increasing the angle as steep as it can possibly go helps, but there is still tugging going on...

Some of this YMMV stuff I just don't understand. My experience is the exact opposite. I prefer to ride the cap with the R41. I also found Feather blades tuggy, but only with steep angle. Weird right? Am I doing something wrong?

 

[SCh5]

A blade “ tugs ” when the stubble cutting angle is far from being
perpendicular .

A smooth cut is achieved when
the blade meets the hair strand
at 90 degrees angle.Then,the blade
edge travels the shorter possible
distance through the hair ,until the
latter is completely cut .
The further the cutting angle is from
90 degrees the longer the distance the
blade has to travel until the hair is completely cut off.
That is experienced as tugging .

The YMMV “rule” is expressed at
it’s maximum here ...
Since every each one of us has
different stubble emerging angles .
Usually the neck area has lower
hair emerging angles that the face .
But there are exceptions too,even there.

So ,while shaver#1 rides the cap
with i.e. R41 and a fresh Feather
and gets a smooth shave ,
shaver #2 rides the bar in
order to get a smooth shave ,
as his stubble grow flatter than those
of shaver #1.

Nothing wrong .Just a typical
YMMV thing .

 

[Al Bundy]

I am one of those for whom rigid blades provide a far more comfortable shave.

Of my regular razors the 3 that fall into this category are Fatip Piccolo mk1, FOCS and Ever Ready 1912. Each of these provides an experience which, in terms of smoothness, is streets ahead of my Muhle Rocca, R41, Parker Variant etc

That's not to say I can't get excellent results with all of them but when I get to the tough spots the rigid ones will get through with much less drama than the others.

Out of curiosity, I understand that slant designs stiffen the blade by providing extra torsion from twisting the blade? With a razor such as the Yaqi DOC slant does this help make up for the otherwise "wild and free" nature of the blade clamping?

 

[DaveHStone]

A smooth cut is achieved when
the blade meets the hair strand
at 90 degrees angle.....

Actually not, have a look:

I'm no expert, but @JohnPS is and he explained this in detail in another post.

 

[Dovo1695]

Some of this YMMV stuff I just don't understand. My experience is the exact opposite. I prefer to ride the cap with the R41. I also found Feather blades tuggy, but only with steep angle. Weird right? Am I doing something wrong?

Lol. No, I always get steep angle vs shallow angle backwards. Riding the cap is what works for me too.

 

[Lord NSIC]

Fellows, if you want a smooth, no nonsense, easy to achieve BBS shave, I wholeheartedly suggest you switch to SE razor.

Amen; I have a bunch of DE razors, but once I tried SE razors I have to make it a point to reach for the DE razors -- I use vintage equipment exclusively and nothing beats a GEM or Ever Ready Lather Catcher, 1912/1914 or MicroMatic shave for a BBS shave with lots of audible feedback. Used my 1901 New GEM Lather Catcher yesterday and I'm now just beginning to feel the stubble come through. As for my DEs, I think my Gillette New Improved holds the blade with the most rigidity and gives the best shave without having to think about it, second would be a '46 Aristocrat and Fat Boys. But I'd take an SE first and foremost.

 

[Dovo1695]

That non-helical twist adds some rigidity, but I have four DE razors that provide a pronounced bend to the blade:

Maggards V3A - it’s like an R41/R89 in the baseplate with a very round, bendy cap. Shaves alright, but not rigid.

RazoRock BBS - lots of bend, lots of baseplate support. Fairly rigid especially when steep instead of shallow (though underatedly efficient used shallow).

PAA el Fantasma - lots of bend and baseplate support. Not as rigid as expected. Can be generous handing out weepers on ATG pass if one isn’t careful.

Ikon X3 - lots of curve, but less baseplate support than something a RazoRock Mamba (based on pretty pictures, not in person experience) and it’s DE Rigidity Royalty. Somehow smoother ATG than the RazoRock BBS even though the narrow baseplate suggested to me the blade would flex/unflex like a mousetrap.

Rigidity is a mysterious thing. I don't really understand it. I personally believe that free end distance, clamping distance, and bend radius are the most important parameters, but I'd be hard pressed to prove it. I also don't think any single parameter is sufficient to create a "rigid" razor. I think you need to get the big 3 right. That said, the proof is always in the pudding. If a razor shaves comfortably, that's all that really counts, and it doesn't really matter what word you call it. I'm not 100% sure that rigidity is real or can be explained mechanically, but I'm 100% sure that shaves can be comfortable.

I’ve read that the lemon was man-made creation (from breeding sour oranges with citron fruits) meaning that we had to make lemons ourselves before life gave them to us.

It sounds like your dislike for the R41 was so strong that you and your washer baseplate channeled the spirits of ancient, Transoxanian arborists (as one does).

I think transoxanian arborists are often unfairly maligned in the popular media these days, which is unfortunate. The presumption tends to be that the lemon was an end goal in itself which seems improbable. Alternatively and perhaps more probably, the lemon owes it's genesis to an illiterate knife packing peasant thinking "I wonder what happens if I cut this bit of this tree, and glue it that tree". I believe this is the true spirit of the transoxanian arborist, and I channel it daily...

 

[Dovo1695]

I don't know whether rigidity is real, whether it matters, or how it happens, but I do know that people have been talking about it for a long time. King C Gillette and his engineers were obsessed with rigidity. Here is a 1925 pamphlet for the Gillette New Improved. Nearly the whole first page is devoted to discussing how the new design is more rigid due the increased bend radius over the clamping fulcrum. It's fascinating stuff!

 

[thombrogan]

Rigidity is a mysterious thing.

Not sure about mysterious, but it should be quiet and not a singing blade of Solingen.

I personally believe that free end distance, clamping distance, and bend radius are the most important parameters, but I'd be hard pressed to prove it.

A force probe/gauge could prove it. More force needed to deflect the edge equals more rigidity.

I also don't think any single parameter is sufficient to create a "rigid" razor.

Nope. And no one quality - not even rigidity - is enough to make a razor good or bad.

If a razor shaves comfortably, that's all that really counts

Indeed. I prefer rigid razors, but they’re not the be-all/end-all for e’erybody.

I'm not 100% sure that rigidity is real or can be explained mechanically, but I'm 100% sure that shaves can be comfortable.

A resistance to deflection and a resistance to what Chris Kirchen calls ”cyclical loading” and the rest of Earth calls “chatter.”