slant like pass

[Galhatz]

Hi,
I experimented with a pass motion where the blade is at an angle, similar to a slant. I had the usual very close shave (Damaskeene, pella)...you know, i thought I'd share...
Comments?

 

[Mick]

Mantic59 talks about the Gillette slide and the J hook.

Have you see the video? Does it resemble what you are doing?

 

[Mr. Flay]

Mantic59 talks about the Gillette slide and the J hook.

Have you see the video? Does it resemble what you are doing?

I routinely use the Gillette slide, especially with my Auto Strops, and I don't get through a shave without a little blade buffing under my chin. I use a modified J-hook (more of a C-hook?) to get those pesky horizontal-grained whiskers growing across my windpipe.

 

[a Rose's thorn]

I don't mean to throw cold water on the topic, but I think the slant (and what you describe as a slant-like blade angle) are over-rated. I think we picture a guillotine chopping our whiskers when we use a slant. It is just hair. Whether we cut it straight or at an angle isn't relevant.

 

[Haggises]

The slant stroke works for me - for DE, SE and straights.

 

[catherix]

Both the Gillette slide and a slant stroke has worked well for me too. And a slant(razor) too.

 

[angelo]

I don't mean to throw cold water on the topic, but I think the slant (and what you describe as a slant-like blade angle) are over-rated. I think we picture a guillotine chopping our whiskers when we use a slant. It is just hair. Whether we cut it straight or at an angle isn't relevant.

I respect your opinion, but... Go to a cooking class and ask if slicing is the same as chopping. Yes, hair is just like vegetables.

 

[Mike H]

What Gillette recommended....

 

[a Rose's thorn]

I respect your opinion, but... Go to a cooking class and ask if slicing is the same as chopping. Yes, hair is just like vegetables.

......

 

[HUF]

I respect your opinion, but... Go to a cooking class and ask if slicing is the same as chopping. Yes, hair is just like vegetables.

+1

 

[rajagra]

I'm unconvinced that even guillotines benefited much from the angled edge. After all, the blade motion is still downwards at every point, and the neck is clamped in place. Has anyone actually seen a proof that the angled blade works better?
I'm pretty certain that slant razors create an angle so small that that particular aspect of the design is insignificant.

However, the Gillette slide works very well. Firstly, you can move in a way that creates a very significant angle. More importantly, I believe that when the blade has difficulty "chopping" straight through a hair, the hair gets pushed along with the blade. Eventually the tension on the hair is enough to overcome friction and it can move sideways because of the angled blade. This creates a slicing effect, and Ping!, bye bye hair.

I may try to make a decent diagram showing this, in the meantime here's a rough draft. Excuse the scrawl!

Spoiler

 

[mblakele]

If the blade pushes the hair, the cut is likely to end up higher on the hair shaft. Hence the shave will be less close.

As for the guillotine, http://tuhsphysics.ttsd.k12.or.us/Research/IB06/JCo/index.htm might interest you.

In my hypothesis, I stated that not only the blades with an angle would fare better than the zero degree angle, but that the angles between 45 and 75 would be the most efficient. In the data table, the angled blades were able to slice through the clay at least seven centimeters before the zero degree angle. The 45 and 75 degree angles were the first to cut through the clay after a 12.065cm drop. My initial reaction to this was that the 60 degree angle would therefore be the best because 60 is the average of the two. However, this was not the case; the 60 degree angle cut through the clay 2 cm after the 45 and 75 degree angles. The 30 degree angle did as well as I expected it to, while the 90 degree one took me by surprise. It seemed unusual that it would cut through the same amount of material at three different heights, but I retested it, and received the same results. The zero degree angle also performed how I thought it would. It tended to smash the area around the cut more than any other angle. The uncertainty here is probably the greatest among any of the other blades because, as aforementioned, the metal sheet that the blade attached to could also hit the clay. Therefore, those numbers would be lower. It is also interesting to note that after a certain height, (19cm), all the blades were able to slice through the clay.

 

[JDTTO]

I never felt like doing the Gillette Slide but a slant/guillotine-like angle works great for me. I have found it to cut smoother than just cutting straight.

 

[Klopstick]

I've done this motion for years with Gems and straights. Works especially well in the hollows of your neck where you want a really light touch. Blades seem to get more life too.

 

[gruntedshaves]

you guys are all talking about how these are ehh and all passes do the same; don't forget all of our hairs grow in ways that resemble a sand drift in a storm. they go where ever the heck they want!

 

[rajagra]

If the blade pushes the hair, the cut is likely to end up higher on the hair shaft. Hence the shave will be less close.

I don't think you've seen videos of beard being cut that show just how jelly-like skin is at this scale. The blade can catch the hair at exactly the same point as if was cut instantly, and pull it quite a way before something happens. Either the blade will skip, or it will cut through, or the hair will slide sideways as in my diagram.
This shows what happens; even without the Gillette slide, the hair catches, is pulled, and cut cleanly: http://www.youtube.com/watch?feature=player_embedded&v=zzDwSK91f8I
I believe the slide makes this more efficient by causing the blade to slice through the hair at an earlier moment.

As for the guillotine, http://tuhsphysics.ttsd.k12.or.us/Research/IB06/JCo/index.htm might interest you.

Interesting, but he is aiming the blade at a flat block of clay instead of a rounded object like a hair or neck. His own hypothesis explains why this is a poor model of how a guillotine works: "because the force of the blade will hit a smaller area, thus slicing the clay better. "

 

[mblakele]

I can tell you feel strongly about this, but I am a touch critical of that video as evidence. It is unsourced, but I suppose it was funded by P&G or another company that sells shaving systems? They had a sale to make. It would have been in their interest to use fresh blades, and try dozens or hundreds of takes to get at least one nice clean cut on video. Would they show us any sloppy cuts, even if they outnumbered the clean ones? So to my mind that video does not necessarily tell us how a cartridge behaves ordinarily, much less the behavior of straight razors, SE blades, or DE blades - especially when folks use them for a week at a time.

I agree that the exact shape makes some difference, but from my own observation my beard hairs are not perfectly round in cross-section. Sometimes square would be an equally good, or bad, approximation.

Another way to look at your "pull-then-slice" idea is that if it is pronounced enough, the shaver will notice tugging or pulling. if so, a slant or slide may yield a more comfortable shave.

Playing devil's advocate to my own position, I think you should point out that any discussion of a blade edge hitting a single hair may be misleading. In real-world conditions, when shaving dense areas, the blade edge is likely to hit half a dozen hairs at once. That mutes any putative reduction in FTC from an angled edge, where the advantage comes from a concentration of force on one point.

Anyway the bottom line is YMMV: some folks prefer a slant over a sliding motion, some find a sliding motion is just as good, and some find that neither approach helps.

 

[rajagra]

Yes, that video is taken from Gillette's lab research into the "hysteresis" effect. But the only point I'm taking from it here is that a blade catches the hair, tugs it out a bit, and eventually the tension causes something to happen.
If I can find the full video, I'll link it. EDIT> Video has gone, but here's what took me to it. Shame, it was informative.

Anyway, here's an animation I made showing what I think happens with the Gillette slide:

In practice, this may happen many times in rapid succession: catch hair, tug a bit, slide and slice a bit, then tug again; repeat until hair is sliced off.

P.S. No, I don't feel strongly about it LOL. And actually I think that video shows how *blunt* they have to make their multi-blades to make the hysteresis effect work. Sharp blades tug less and wouldn't pull out enough "extra" hair for the next cut.