How does a multiblade razor work?

[schmmd]

I've heard people say that they are designed to pull up hairs and then cut them, but I don't really understand how that works. How do 3 blades cut and what is the justifying theory that 3 blades are better than 1? The only source I found find was:

http://www.theonion.com/content/node/33930

Oh, and I looked at the Gillette website, which is probably the worst website I have ever seen (and all it says is shave everything 4x a day with the Fusion).

 

[DunEdinRanger]

If you can't believe The Onion, who can you believe?

The theory behind may be good, but in actuality a single edge works better.

 

[greyalien]

The Onion as a source

 

[schmmd]

If you can't believe The Onion, who can you believe?

The theory behind may be good, but in actuality a single edge works better.

I'm with you on that, but I don't even understand how the physics of the theory work. How do 3 blades lift and cut?

 

[greyalien]

I'm with you on that, but I don't even understand how the physics of the theory work. How do 3 blades lift and cut?

Essentially, the first blade grabs the whiskers and yanks them out from the skin a little so then the other two...or three...or four blades can come through and chop them off at a point which is normally below the skin. Ouch. My face doesnt like it one bit.

 

[schmmd]

Essentially, the first blade grabs the whiskers and yanks them out from the skin a little so then the other two...or three...or four blades can come through and chop them off at a point which is normally below the skin. Ouch. My face doesnt like it one bit.

So is the first blade different than the other ones? How can the first blade hold up a hair while FOUR MORE BLADES cut it? That seems like a long stretch of a hair...

 

[Millay]

Essentially, the first blade grabs the whiskers and yanks them out from the skin a little so then the other two...or three...or four blades can come through and chop them off at a point which is normally below the skin. Ouch. My face doesnt like it one bit.

Iwonder if the ouch point is to do with the speed at which this happens, and obviously the lack of sharpness in these baldes?

I say this because you need a fast pull to catch the hair that has been pulled by the first blade. Then, should you not be concerned that a blade is pulling a hair that much before cutting it?

Also what then is the third + blade for? just scraping off a layer of skin after the second blade has pulled it up?

 

[talibeard]

Essentially, the first blade grabs the whiskers and yanks them out from the skin a little so then the other two...or three...or four blades can come through and chop them off at a point which is normally below the skin. .

That is the theory indeed but the TV commercial by gillette in the late 70's or early 80's that showed this process by a sort of comic was banned by law (in my country at least) because they couldn't come up with any evidence...

 

[Luc]

There was a doco on youtube made in the Gillette headquarters in London.

See post #15...
http://badgerandblade.com/vb/showthread.php?t=89206

 

[_JP_]

So is the first blade different than the other ones? How can the first blade hold up a hair while FOUR MORE BLADES cut it? That seems like a long stretch of a hair...

The idea is that the hair has not yet retracted from the first blade, so the second blade is able to get a hold of it. And the process repeats itself with any remaining blades. But you have to do your part and be moving the razor fast enough for it all to work.

 

[reub2000]

So is the first blade different than the other ones? How can the first blade hold up a hair while FOUR MORE BLADES cut it? That seems like a long stretch of a hair...

Whenever a steel blade doesn't simply slice through the hair, it pulls on it a little bit before going through.

Another part of the theory is that the pressure on the head of the razor is evenly dispersed among the blades. Keep in mind that they are meant to be used with considerable pressure. It's basically meant to be an idiot proof system.

 

[r0ckrat]

It's basically meant to be an idiot proof system.

But, isn't that an oxymoron? Especially since the most oft mentioned thing on this forum is that anyone who uses more than a single edge is an idiot...

disclaimer: I neither agree nor disagree with any comments I might have made prior to this disclaimer. To each his own, and peace be with you.

 

[FFJim]

Essentially, the first blade grabs the whiskers and yanks them out from the skin a little so then the other two...or three...or four blades can come through and chop them off at a point which is normally below the skin. Ouch. My face doesnt like it one bit.

That is why I got into DE in the first place...lift/cut/rip...those days are gone for me.

 

[mmack66]

The 2-blade systems worked in the lift and cut method, but I believe the Mach3 and Fusion operate on the principle of each blade shaving you closer than the last. I seem to recall some talk about each blade being optimally angled to do just that. I also believe that the each blade shaving closer than the last concept is what creates the uncomfortable dragging sensation of those razors.

 

[kingfisher]

The 2-blade systems worked in the lift and cut method.....

Well, I don't know that anybody has any proof of this. That was certainly the dogma at the time. I find it doubtful it really works this way.

 

[mmack66]

Well, I don't know that anybody has any proof of this. That was certainly the dogma at the time. I find it doubtful it really works this way.

Well, the Good News had a tv ad about it than can be found somewhere on the internet. Perhaps the TracII and Atra were different. The Sensor had floating blades, so I don't know the theory behind that one. Any thoughts I have about the cutting physics of the various cartridges is mere speculation, though.

 

[schmmd]

Well, the Good News had a tv ad about it than can be found somewhere on the internet. Perhaps the TracII and Atra were different. The Sensor had floating blades, so I don't know the theory behind that one. Any thoughts I have about the cutting physics of the various cartridges is mere speculation, though.

http://www.youtube.com/watch?v=cd8ThwHKV6g

I've always wanted a shave so fine a baby could slap me in the face...

 

[HoratioCaine]

The Sensor had floating blades, so I don't know the theory behind that one. Any thoughts I have about the cutting physics of the various cartridges is mere speculation, though.

I'm just speculating, too, of course, but the floating design might help with lift-and-cut, since the first blade won't slice through as readily as a fixed blade, since it will give to the pressure of the whisker. Thus, there would be even less time between the cut of the first blade and the time the second blade contacts the hair. I don't know if it's worth noting, but all Gillette cartridges since the Sensor incorporated the floating blade design, so if what I say has any merit at all, it would apply to the M3 and Fusion as well.

 

[HoratioCaine]

http://www.youtube.com/watch?v=cd8ThwHKV6g

I've always wanted a shave so fine a baby could slap me in the face...

"So shaving feels so good..."

Yeah, and nothing feels so good as swiping a pair of blades from my ear to my chin in one fell swoop, irrespective of beard growth direction, pressure, or any of the other variables in technique that make for a good shave. Sheesh.

And today's ads feature the same long stroke. Double sheesh.

 

[grouse79]

The blade razor I usually used after stopping using the electric was the Mach3 Power. Gillette said some guff about micropulses lifting the hairs or something. Whatever it was, I always used it with the power on and when the batteries went flat, it scraped something terrible. My theory was the vibrations were making the blades only in contact with my skin for a short time. Considering the way I shaved then - one application of usually cold gel followed by about a dozen frenzied passes all over the place - I'm amazed I didn't cut myself more.

If I had a choice in the matter, I'd never go back to the Mach3.