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

Your evaluation is just fine except for one basic flaw. Your definitions of the scything stroke and guillotine stroke don't match the definitions used in this forum. You're altered definitions suit your conclusions, but this forum's conventions don't match your definitions and therefore your conclusions don't follow.

Originally Posted by Utopian

Your evaluation is just fine except for one basic flaw. Your definitions of the scything stroke and guillotine stroke don't match the definitions used in this forum. You're altered definitions suit your conclusions, but this forum's conventions don't match your definitions and therefore your conclusions don't follow.

To a certain extent, I agree with you (although my definition of a guillotine cut is exactly in line with the wiki). Regarding scything and slicing, they are used rather differently around the forum. Slicing is particularly poorly defined. I came to the definition above to provide a more useful, concrete description. Regarding scything, I have seen it used in the forum as I have defined it and also as the wiki defines it (involving a pivoting motion). I agree that the above definition differs from the wiki.

However, I had no preconceived notions when I started exploring this topic, and certainly didn't intentionally alter definitions to support them. I'm a math guy. I was making diagrams and doing some trig because it's fun. The conclusions came directly from the math. The definitions were made to make the math possible.

Finally, regarding the wiki defined scything, the math is somewhat different than this problem. I will work on that soon - probably will use polar coordinates/functions.

Originally Posted by ixtapalapaquetl

To a certain extent, I agree with you (although my definition of a guillotine cut is exactly in line with the wiki). Regarding scything and slicing, they are used rather differently around the forum. Slicing is particularly poorly defined. I came to the definition above to provide a more useful, concrete description. Regarding scything, I have seen it used in the forum as I have defined it and also as the wiki defines it (involving a pivoting motion). I agree that the above definition differs from the wiki.

However, I had no preconceived notions when I started exploring this topic, and certainly didn't intentionally alter definitions to support them. I'm a math guy. I was making diagrams and doing some trig because it's fun. The conclusions came directly from the math. The definitions were made to make the math possible.

Finally, regarding the wiki defined scything, the math is somewhat different than this problem. I will work on that soon - probably will use polar coordinates/functions.

So, I guess my conclusion has been wrong all this time...










...shaving really is rocket science.

OK, go ahead and do that, but the analysis can also be done with a knife and a tomato. Around here people call the scything motion a rotational motion. I don't agree with that definition as it does not match the motion of a scythe blade's motion relative to the grass it is cutting. For the guillotine motion, which I consider to be the same as a scything motion, the horizontal blade is moved down in a toe or heel leading North West to South East motion with the blade held horizontal. In other parts of the Wiki the guillotine is when the blade is held in a NW to SE orientation and then is moved straight down.

Regardless of any semantics or mathematical analyses, everyone knows that a tomato is better cut with a slicing motion rather than a straight down motion. Shaving works the same way.

Tomayto
Tomahto

There is a lot of work in that original post. We always appreciate those with a pssion for this stuff.

I have seen so many arguments about guillotine or scything motions and each has been described differently by different people.

In my opinion a video with the motions correctly described and demonstrated will help anyone reading the wiki. That way there won't be anymore confusion and arguments about the motions.

Originally Posted by basil

I have seen so many arguments about guillotine or scything motions and each has been described differently by different people.

In my opinion a video with the motions correctly described and demonstrated will help anyone reading the wiki. That way there won't be anymore confusion and arguments about the motions.

That can never really happen... There is always going to be a bit of give and take on the correct motion because the correct motion follows the direction of the hair in the beard and is done by feel... So if I do a video, and say this is correct, it is for me, and anyone else whose beard follows mine, BUT if your beard has a different growth pattern, the motion is going to be slightly different to cut your hair better...

IE:

If I were to demonstrate a simple WTG pass on my face I have to use three different directions for this demonstration in regards to N-S-E-W

Originally Posted by gssixgun

That can never really happen... There is always going to be a bit of give and take on the correct motion because the correct motion follows the direction of the hair in the beard and is done by feel... So if I do a video, and say this is correct, it is for me, and anyone else whose beard follows mine, BUT if your beard has a different growth pattern, the motion is going to be slightly different to cut your hair better...

Cmon Glen. You and I both know there is only one "true way" and that is a closely guarded secret among the SRP elite

True I forgot about that.
But it still could be helpful for newbies to see and then adjust to suit their needs.

Originally Posted by basil

I have seen so many arguments about guillotine or scything motions and each has been described differently by different people.

In my opinion a video with the motions correctly described and demonstrated will help anyone reading the wiki. That way there won't be anymore confusion and arguments about the motions.

I agree entirely. This post was an attempt at movement in that direction. It may come to pass that some definitions are simply more functional than others.

As I said, I will discuss the rotating scythe cut at another time. I haven't worked anything out yet, but the sketch I have in my head suggests that the rotational scythe cut is actually less of an ideal stroke than the scythe stroke here (specifically because a razor is straight, and not curved like a scythe). However, I can't say for certain until I actually play with the mathematical model.

Again, I have no bias, I am just doing some math. Truth be told, knowing all this I still use a straight cut a fair portion of the time!

Now tell me more about this list...