Thread: Analysis of the Scythe and Guillotine Cuts. Spoiler: they are the same thing.

This interests me alot as I have no idea what strokes I do when shaving, I tilt my head and the blade, sometimes keeping the hand slightly stationary and doing a sort of stroke you would do when drawing a circle with a compass - sort of half moon - and sometimes a cut where the razor is at a diagonal cutting in a straight line, whatever cuts the hair off my face without nicking it really.

I don't know I've learned alot of different subjects and for me sometimes terminology and labels just slow ya down and get in the way, but I still love it when someone can explain a complex action in succinct, cogent terms

hopefully an umpire wont be needed

Originally Posted by JimmyHAD

More Ahab I think ...... I'd rather be Ishmael.

Yep - you nailed it like a gold doubloon on the side of the main mast.

Originally Posted by Utopian

No, it won't.

I apologize to the OP (I'm not going to try to spell out your username!). I work in a scientific field (and also I'm a bit of an @ss) and I have a habit of being confrontational with insufficient tact. I usually don't intend anything personal by it and certainly didn't this time. As Alembic mentioned, I've "discussed" the scythe issue before. Apparently, I'm one of the few on here that has used an actual scythe, so I seem to be one of the few who grasps the actual cutting stroke of a scythe. For that reason, I have continued to disagree with the idea of the shaving stroke being rotational.

Einstein worked out many of his greatest achievements with thought experiments that he later elaborated upon with mathematical explanations. I'll stick with my tomatos but I'd be glad to see your mathematical analyses!

Just a thought - but several of us have tried to create the glossary as we see it - with varying degrees of agreement and success. I'm not sure if you have done so, but maybe it would be good if you did so we can lay to rest the vocabulary.

I reachin out with an olive branch here, I hope you don't scythe it, or shear it, or....

I think most of us here are a bit tactless.....we are the male of the species.
But the good thing is as the male of the species we seldom hold grudges!

I do not only have a scythe, but when I was younger I spent hours and days using one, and the one I have is curved. The problem with defining the scything motion is that we are not using a scythe, making that a misnomer from the get go. Because a scythe is curved it has differential velocity and force vectors and we can not duplicate that with a straight razor. I think the OP did a reasonable job with his models and the math seems reasonable.

When shaving I personally use a couple of different motions.

1. I use a toe or heal leading motion with a slicing motion that moves from heel to toe, or toe to heal.
2. I use a arched sweep that is coupled with a slicing motion as I make the arch.
3. I use a flat slicing motion on my chin and sideburns.

I honestly feel that it does not matter motion is use because if someone attempts some of the motions mentioned he will develop a technique that will work for him. I, myself am constantly learning so these threads are great!


Later,
Richard

Originally Posted by gssixgun

Those are hints at something your missing

That just has to do with what you are not taking into account with blade dynamics let alone when you throw it the fact that many of us hone and strop a special way just to always keep the striations on the edge the same for a more efficient cutting edge

Would that be the ultra-secret scything stropping motion? Following up on the mystery-shrouded guillotine honing stroke, it makes for a deadly shave, assuming the secret handshake has been used and the plasma-slurry is at the right density...

Okay, I'm taking my hones out of the microwave now, their molecular density is perfect for honing those new titanium straights!

One thing I always miss in these discussions, that I think matters as much as the angle of cut, is the way the stroke helps to keep the razor in close contact with the face as we move it over the contours of the face.

I use a kind of rotational stroke sometimes not because the math of the cut is better, but it seems the most effective way to handle that part of my face.

No stroke, however efficient at cutting, will shave well if the faces contours interfere with the edge's contact with the skin.

Originally Posted by LawsonStone

One thing I always miss in these discussions, that I think matters as much as the angle of cut, is the way the stroke helps to keep the razor in close contact with the face as we move it over the contours of the face.

I use a kind of rotational stroke sometimes not because the math of the cut is better, but it seems the most effective way to handle that part of my face.

No stroke, however efficient at cutting, will shave well if the faces contours interfere with the edge's contact with the skin.

You know - I agree with this. There are some stroke styles that when matched up with beard growth direction and facial contour are just not going to be the most efficient, but whatever the shaver can manage to pull off - irrespective of what you call it.

Originally Posted by LawsonStone

Would that be the ultra-secret scything stropping motion? Following up on the mystery-shrouded guillotine honing stroke, it makes for a deadly shave, assuming the secret handshake has been used and the plasma-slurry is at the right density...

Okay, I'm taking my hones out of the microwave now, their molecular density is perfect for honing those new titanium straights!

LOL
No I was hinting at the fact that everyone keeps saying a straight edge...

The was to give the hint that a smiling edge which is considered to be the "Easiest" to shave with by many, is ALWAYS scything as it is shaving... Much like the inside curve of a real Scythe the outside curve of a smile in many razors, and that are intentionally honed into many razors edges, helps create that effect with every cutting pass....

Combined with the fact that many of us actually hone the razor so that every single stroke creates striations that look like this ///////// on a straight edged razor, intentionally to help with every cutting stroke and actually Strop exactly in the reverse of those to keep all the striations in alignment thus also creating a scything effect when cutting....

All this is also part of shaving, but is being glossed over...

Originally Posted by hi_bud_gl

check this one out and may help .

http://ep.yimg.com/ca/I/yhst-6589063...0_2091_8715077

I know I'm new but... it sure seems those granite counter tops look equally well shaved to me...

Originally Posted by gssixgun

LOL No I was hinting at the fact that everyone keeps saying a straight edge...

I caught your meaning. It is often useful when tackling a new problem to simplify matters to the greatest extent possible. Once a basic understanding is reached, then levels of complexity can be layered back in. Such is the case with a smiling blade. I would like to finish the rotational scything case before moving into this territory. And to be honest, as you have suggested, there is only so much a simple model can do. There will always be subtle variables resulting from the human element that cannot be tractably represented. Thus, I keep my aims limited.

I was not aware of the angled honing technique you suggested. That said, I have a question. Ultimately, isn't the tip of the edge the only part doing the cutting? If so, don't //////// and \\\\\\\\ look the same at the point of contact on the skin with the razor (namely .........)? It is plausible that honing at an angle such as this will result in closer striations relative to straight honing, and I could see that impacting the final edge, but for a blade held at 20 degrees and a bevel of 17 degrees, the striations aren't even in contact with the skin, so their presence along the non-cutting portion of the blade seems irrelevant?

What am I missing?