How a razor blade can be damaged as it cuts human hair (2020)(news.mit.edu)
news.mit.edu
How a razor blade can be damaged as it cuts human hair (2020)
https://news.mit.edu/2020/why-shaving-dulls-razors-0806
137 comments
Neither of the two videos embedded in the linked press release shows any damage to the blade of the razor. They each cut out at the point that the blade has just finished slicing through a hair, while the hair is still in contact with the blade edge and obscuring our view of any hypothetical chips or defects caused by the cutting process. Bizarre.
The first SEM video shows a small-omega shaped scallop in the blade after it cut the hair. It is indeed a shame this is only visible in the final handful of frames before the video loops.
For me though it didn’t detract too much from the awe. What an incredible result.
For me though it didn’t detract too much from the awe. What an incredible result.
What I see there is the cut edge of the hair overlapping the blade rather than any change in the blade itself.
The videos are very cool and I appreciate cool videos, but I don't see any evidence in them for the claim of capturing damage to the blades. It's possible that the press release omits clearer videos that unequivocally show damage to the blades during cutting.
The videos are very cool and I appreciate cool videos, but I don't see any evidence in them for the claim of capturing damage to the blades. It's possible that the press release omits clearer videos that unequivocally show damage to the blades during cutting.
There are videos in the supplemental to the paper, see https://www.science.org/doi/10.1126/science.aba9490
I love figure S5, it belongs in the surprisingly large family of "physics experiments involving the researcher's own hair" ("cross hairs" on a telescope were originally made from hair or spider silk).
I don't know why you mentioned s5...
s3 is good though. It actually shows some chips.
s3 is good though. It actually shows some chips.
Or it's also possible some grad students with a null hypothesis result are hyping their own startup idea - they have a patent on making better steel for such high toughness applications. Surely that's a technology that would have wide impact on a large number of industries, they probably chose razors as a low mass, high value MVP and hope to scale up.
I mean that's the zebra, yes. The horse is they just cut the video a bit too early and didn't watch it after doing so.
> The researchers have filed a provisional patent on a process to manipulate steel into a more homogenous form, in order to make longer-lasting, more chip-resistant blades.
How is that specific to razor blades? Surely this scenario of sharp bendy steel blade meets soft material is common across many industries.
For those interested in the SEM images and looking for more, check out this site: https://scienceofsharp.com/home/
The site focuses mainly on sharpening razor blades and is full of SEM images of blades in various conditions. Very cool to see.
This page about burrs has some particularly cool images: https://scienceofsharp.com/2015/01/13/what-is-a-burr-part-2/
The site focuses mainly on sharpening razor blades and is full of SEM images of blades in various conditions. Very cool to see.
This page about burrs has some particularly cool images: https://scienceofsharp.com/2015/01/13/what-is-a-burr-part-2/
> The team’s findings may also offer clues on how to preserve a blade’s sharpness. For instance, in slicing vegetables, a chef might consider cutting straight down, rather than at an angle. And in designing longer-lasting, more chip-resistant blades, manufacturers might consider making knives from more homogenous materials.
I'm no knife expert, but my understanding is that today's best knives use VG-10 steel, which is designed to "chip itself to make itself sharper". So its hard, flexible, slightly more brittle than you'd expect. But these micro-chips end up sharpening the blade more often than not. There's more than one way to design a blade's metallurgy.
For shaving steel, it needs to be as cheap and flexible as possible, so that machines can mass produce them. High end knife-blanks cannot be punched if the steel is too hard or strong (leading to a "price cliff", where the best steels are an order of magnitude more expensive than the punchable lower-cost steels).
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So yes, very interesting experiment. But also consider the overall picture: chip-resistance isn't everything.
I'm no knife expert, but my understanding is that today's best knives use VG-10 steel, which is designed to "chip itself to make itself sharper". So its hard, flexible, slightly more brittle than you'd expect. But these micro-chips end up sharpening the blade more often than not. There's more than one way to design a blade's metallurgy.
For shaving steel, it needs to be as cheap and flexible as possible, so that machines can mass produce them. High end knife-blanks cannot be punched if the steel is too hard or strong (leading to a "price cliff", where the best steels are an order of magnitude more expensive than the punchable lower-cost steels).
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So yes, very interesting experiment. But also consider the overall picture: chip-resistance isn't everything.
These ideas are mistaken.
"Sharpness" is related to the physical size and radius of curvature of the apex of the blade, combined with the angle of the terminal bevel. [1][2][3]
Chipping of any sort almost certainly tends to erode the sharpness for many reasons, not least of which is that a sharp edge is a very low entropy state (compared to a dulled / chipped / etc edge...).
VG-10 steel is considered "entry level" in terms of high end steels. [4] It was first introduced in production knives in the mid-90s, almost thirty years ago! [5] And there has been significant progress in materials since then.
Almost all mid- and high-end knives these days are cut from blanks via an industrial laser or waterjet cutter.
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[1] https://scienceofsharp.com/2014/01/25/quantifying-sharp/
[2] https://scienceofsharp.com/2014/08/18/definitions-of-sharp-a...
[3] https://scienceofsharp.com/2015/03/24/sharp-and-keen-part-2/
[4] https://www.bladehq.com/cat--Best-Knife-Steel-Guide--3368
[5] https://forum.spyderco.com/viewtopic.php?t=87185
"Sharpness" is related to the physical size and radius of curvature of the apex of the blade, combined with the angle of the terminal bevel. [1][2][3]
Chipping of any sort almost certainly tends to erode the sharpness for many reasons, not least of which is that a sharp edge is a very low entropy state (compared to a dulled / chipped / etc edge...).
VG-10 steel is considered "entry level" in terms of high end steels. [4] It was first introduced in production knives in the mid-90s, almost thirty years ago! [5] And there has been significant progress in materials since then.
Almost all mid- and high-end knives these days are cut from blanks via an industrial laser or waterjet cutter.
-----
[1] https://scienceofsharp.com/2014/01/25/quantifying-sharp/
[2] https://scienceofsharp.com/2014/08/18/definitions-of-sharp-a...
[3] https://scienceofsharp.com/2015/03/24/sharp-and-keen-part-2/
[4] https://www.bladehq.com/cat--Best-Knife-Steel-Guide--3368
[5] https://forum.spyderco.com/viewtopic.php?t=87185
Interesting - I noticed that the edges of some new knives that are very sharp don't feel or look smooth. I usually sharpen my kitchen knives on a standard stone and get them very smooth, which I like aesthetically but probably not the most efficient for, say, cutting tomatoes.
Could you clarify a little more about what you mean by this? Tomato skins are definitely hard to cut with a dull knife (without crushing the tomato flesh underneath), so many people will default to using a serrated knife for them, hoping that the scalloped edge grabs and tears the skin.
That said, a well sharpened kitchen knife should have no problem at all with tomato skins.
That said, a well sharpened kitchen knife should have no problem at all with tomato skins.
What I mean is that I can sharpen my knives (traditional Zwilling or Wuesthofs) on a stone until they are nice and sharp and when I run them along a towel nothing catches.
I noticed that when I got a new knife recently it didn't feel smooth at all, more like it had lots of microscopic burrs. That knife cut through (thickish garden) tomato skins more readily, even after weeks of knife use. Eventually I had to resharpen that knife and I just find that even though I can get it nice and sharp the type of edge I put on the knife doesn't last as long.
And yes, when I cut a lot of tomatoes I might use a serrated knife but in normal use I don't like to switch so much so I do almost everything with a 8 or 9" chef knife.
I noticed that when I got a new knife recently it didn't feel smooth at all, more like it had lots of microscopic burrs. That knife cut through (thickish garden) tomato skins more readily, even after weeks of knife use. Eventually I had to resharpen that knife and I just find that even though I can get it nice and sharp the type of edge I put on the knife doesn't last as long.
And yes, when I cut a lot of tomatoes I might use a serrated knife but in normal use I don't like to switch so much so I do almost everything with a 8 or 9" chef knife.
Wait a second, those micro-chips end in the cut food pieces, right? How "micro" are those and how much of those are made on average in a cutting session? I am pretty sure that steel dust, starting from some size of specks and general amount of it, is not very healthy for internal consumption so I'd like to learn more.
On the contrary, dietary iron, the kind you need, is just iron. There's a fairly common science demonstration where you blend up fortified breakfast cereal (I saw it done with corn flakes) and pass a magnet over it. The magnet will pick up a bit of iron dust.
The amount of steel flaking off a knife into any given meal is likely much smaller than how much iron is in the food on its own merits.
The amount of steel flaking off a knife into any given meal is likely much smaller than how much iron is in the food on its own merits.
There's also using cast iron to introduce iron into the diet.
Food prepared in iron cooking pots as an intervention for reducing iron deficiency anaemia in developing countries: a systematic review - https://pubmed.ncbi.nlm.nih.gov/12859709/
It's also something that many vegans have looked into https://plantprosperous.com/cast-iron-cooking-for-vegans/ (which links to the above article too - though I found the nih one first)
My search-fu is failing me at the moment, but that was also believed that this was an important part of the pioneers heading west in the early parts of United States history.
Food prepared in iron cooking pots as an intervention for reducing iron deficiency anaemia in developing countries: a systematic review - https://pubmed.ncbi.nlm.nih.gov/12859709/
It's also something that many vegans have looked into https://plantprosperous.com/cast-iron-cooking-for-vegans/ (which links to the above article too - though I found the nih one first)
My search-fu is failing me at the moment, but that was also believed that this was an important part of the pioneers heading west in the early parts of United States history.
> Food prepared in iron cooking pots as an intervention for reducing iron deficiency anaemia in developing countries
I believe also a little iron fish is sometimes introduced into the non iron pot during cooking.
I believe also a little iron fish is sometimes introduced into the non iron pot during cooking.
That's the first I've heard of it... so I looked it up.
https://brightthemag.com/lucky-iron-fish-raise-questions-abo... and https://pubmed.ncbi.nlm.nih.gov/28049274/
https://brightthemag.com/lucky-iron-fish-raise-questions-abo... and https://pubmed.ncbi.nlm.nih.gov/28049274/
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I remember seeing that on Bill Nye.
Those micro-chips exist on all knives through all kinds of cutting.
VG10 just is designed for those chips to sustain the sharpness of the knife, so it requires less sharpening. You can look at the ends of any knife that's been worn away, and its not as smooth as when it was originally sharpened.
The knife's edge is the thinnest part of steel, and may only be a few atoms thick when properly sharpened. It doesn't take much for it to chip off.
VG10 just is designed for those chips to sustain the sharpness of the knife, so it requires less sharpening. You can look at the ends of any knife that's been worn away, and its not as smooth as when it was originally sharpened.
The knife's edge is the thinnest part of steel, and may only be a few atoms thick when properly sharpened. It doesn't take much for it to chip off.
I don’t have anything useful to say other than damn I love SEM movies!
I bought a Celestron USB microscope. It was fascinating to look at my skin, nails, desk surface, carpet, anything. Well, at least for the 15 minutes before the device failed. I returned it and never bought a replacement. :-(
Has anyone had luck with a toy-ish microscope in the $200 range?
I bought a Celestron USB microscope. It was fascinating to look at my skin, nails, desk surface, carpet, anything. Well, at least for the 15 minutes before the device failed. I returned it and never bought a replacement. :-(
Has anyone had luck with a toy-ish microscope in the $200 range?
I picked up a Carson MicroBrite Plus for the same purpose -- looking at clothes/newsprint/etc and it works pretty well. It claims to do 60-120x magnification. No easy way to capture the images but it makes for a good toy.
Would be interested in a recommendation for something with higher magnification
Would be interested in a recommendation for something with higher magnification
You can take a webcam (as long as it doesn't do auto-gain control or auto-focus) and stick it on the eyepiece to capture video/stills.
Or your phone works too
I have a Celestron scope. It has worked fine for all of the years I've had it, though it doesn't give live video out to the PC itself, just to its own internal monitor.
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The researchers have filed a provisional patent on a process to manipulate steel into a more homogenous form, in order to make longer-lasting, more chip-resistant blades.
Considering what started the whole idea of the consumables industry, a patent on making razor blades longer-lasting seems incredibly ironic.
Considering what started the whole idea of the consumables industry, a patent on making razor blades longer-lasting seems incredibly ironic.
Just charge more for the longer-lasting blades. Don't forget to make them incompatible with every other product on the market except your own proprietary, overpriced handle.
I imagine there's already a steel capable of this task as well. Razor makers would choose their steel based on cost/performance tradeoffs not because they're already at the bleeding-edge of steelmaking technology.
The patent would keep other companies FROM making longer-lasting razors.
That's the real dark side of patent law - its used by the entrenched businesses FROM competitors entering the market with better technology for up to 17y.
That's exactly how we got Reprap so late - Stratasys patented the whole lot of 3d printing tech, and the patent didnt expire until 2011.
That's the real dark side of patent law - its used by the entrenched businesses FROM competitors entering the market with better technology for up to 17y.
That's exactly how we got Reprap so late - Stratasys patented the whole lot of 3d printing tech, and the patent didnt expire until 2011.
This study should be considered along with that from metallurgist John Verhoeven, who thought the main cause of chipping is corrosion. (https://knifesteelnerds.com/2021/01/11/what-causes-razor-bla...)
What both these studies reveal is an absence of bending of the sharp edge, indicating that the tradition of razor stropping has no real effect.
What both these studies reveal is an absence of bending of the sharp edge, indicating that the tradition of razor stropping has no real effect.
> indicating that the tradition of razor stropping has no real effect
Indicating that if stropping does help, it's not by the obvious/expected mechanism of bending the sharp edge back.
Indicating that if stropping does help, it's not by the obvious/expected mechanism of bending the sharp edge back.
I don't shave with a straight razor, but I do sharpen carving tools for woodworking.
I strop with a fine honing compound on the strop, and the purpose of that for my application is to get a more highly polished edge than I get off of stones. The[0] explanation among woodworkers being that a more polished edge has fewer micro serrations along the edge that create weak points on the edge for dulling to start. If the edge has fine points from coarser (relatively) stones, they can break off, leaving a definitely non-sharp region behind. Or something like that.
Other tools that are frequently stropped include drawknives. Chisels and plane irons are less commonly stropped because the softer strop inevitably reduces the flatness of the blade at the cutting edge[1].
[0] Ok, one explanation. Some woodworkers will argue bitterly about anything related to sharpening.
[1] The importance of which is another topic that woodworkers will argue endlessly.
I strop with a fine honing compound on the strop, and the purpose of that for my application is to get a more highly polished edge than I get off of stones. The[0] explanation among woodworkers being that a more polished edge has fewer micro serrations along the edge that create weak points on the edge for dulling to start. If the edge has fine points from coarser (relatively) stones, they can break off, leaving a definitely non-sharp region behind. Or something like that.
Other tools that are frequently stropped include drawknives. Chisels and plane irons are less commonly stropped because the softer strop inevitably reduces the flatness of the blade at the cutting edge[1].
[0] Ok, one explanation. Some woodworkers will argue bitterly about anything related to sharpening.
[1] The importance of which is another topic that woodworkers will argue endlessly.
I think stropping is still required after sharpening. But during shaving it might not do anything as indicated by the findings.
Stropping definitely is required after sharpening. Without stropping, you get a pretty harsh shave.
What we need is before and after microscopy to see just what effect stropping has. It seems like an obvious idea to me, but I haven't found any.
There are a large number of electron microscope images here showing the results of various sharpening tools including strops with and without added abrasives.
https://scienceofsharp.com/home/
https://scienceofsharp.com/home/
Thanks. Those studies are interesting, although after reading What Does Stropping Do? I feel like I still don't have a clear answer on whether it does any good to strop before shaving. The photo evidence seems really ambiguous.
It straightens and sharpens the edge, which is likely to improve the shaving experience.
It's unconventional, but I use an abrasive when stropping my straight razor (quarter micron diamond paste), which greatly increases the sharpening effect and reduces the need for other sharpening (traditionally, honing on stones).
It's unconventional, but I use an abrasive when stropping my straight razor (quarter micron diamond paste), which greatly increases the sharpening effect and reduces the need for other sharpening (traditionally, honing on stones).
> When he analyzed the SEM images and movies taken during the cutting experiments, he found that chips did not occur when the hair was cut perpendicular to the blade. When the hair was free to bend, however, chips were more likely to occur. These chips most commonly formed in places where the blade edge met the sides of the hair strands.
Extending the life of a razor blade sounds nice, but cutting hair perpendicular to the blade means shaving against the grain, does it not? I don’t want to handle the pain of doing that on the first or second pass while the hair is still long enough (like a couple of millimeters or longer, which cannot be trimmed using a trimmer and needs a blade). But shaving against the grain gives the smoothest skin texture (at the risk of causing ingrown hair, which for me is quite rare).
What I’m saying is that I’d rather the blades dull and need replacement sooner than put up with the burn and pain caused by shaving against the grain from the get go. A few passes with the grain and perpendicular to the grain (sideways) helps the “against the grain pass” be less painful and provide a smoother result.
I’d still love a blade that lasts longer though.
Extending the life of a razor blade sounds nice, but cutting hair perpendicular to the blade means shaving against the grain, does it not? I don’t want to handle the pain of doing that on the first or second pass while the hair is still long enough (like a couple of millimeters or longer, which cannot be trimmed using a trimmer and needs a blade). But shaving against the grain gives the smoothest skin texture (at the risk of causing ingrown hair, which for me is quite rare).
What I’m saying is that I’d rather the blades dull and need replacement sooner than put up with the burn and pain caused by shaving against the grain from the get go. A few passes with the grain and perpendicular to the grain (sideways) helps the “against the grain pass” be less painful and provide a smoother result.
I’d still love a blade that lasts longer though.
Switch to double edge razors and you won’t care about the blades again. They only cost a few cent when they aren’t wrapped in a proprietary plastic holder.
I think they're more commonly called "safety razors", at least in the USA.
They are $10 for 100-blades, extremely cheap, very sharp, very good at cutting. I highly recommend them.
I only shave twice per razor. Some people shave once-per-razor (throwing away a blade each day). Its just 10-cents a blade after all...
They are $10 for 100-blades, extremely cheap, very sharp, very good at cutting. I highly recommend them.
I only shave twice per razor. Some people shave once-per-razor (throwing away a blade each day). Its just 10-cents a blade after all...
Interesting shaving doesn't feel painful at all to me. No matter which way I do it. Well unless I cut myself.
My problem is I have sensitive skin, and don't feel the cuts at all - which happen much more easily when the blade is slightly dull. Shaving against the grain is a sure fire way to have folliculitis for the next couple of days - as it is I really can't clean shave every day if I want to actually look presentable.
Double Edge shaving solved a similar problem for me. I used to get irritation every time I shaved ATG but that was because I was hitting the wrong side of my face with 5 blades.. Now I can shave easily ATG just by using light pressure and doing WTG first.
Wow for me even trimming it hurts so much I can't sleep well the next night
There are some good videos out there that can give you good tips for avoiding this.
The two biggest things for me were using a shaving oil rather than a cream, and shaving first with the grain and then across.
The latter required more time as my facial hair is very thick and the “direction” seems to change a lot on my face.
The two biggest things for me were using a shaving oil rather than a cream, and shaving first with the grain and then across.
The latter required more time as my facial hair is very thick and the “direction” seems to change a lot on my face.
I think it's genes that determine the shaving pain threshold.
I can shave with a dull blade, completely dry, against the grain, in any direction, and it doesn't bother me a bit. Occasionally I'll cut myself and not notice.
(I don't use a dull blade since it's not efficient, but I'll use one if nothing else is available.)
If it is gene based, I'm not sure if it's something that moderates pain tolerance, hair / keratin composition, or some combination. I can grow a really thick beard, fwiw.
I can shave with a dull blade, completely dry, against the grain, in any direction, and it doesn't bother me a bit. Occasionally I'll cut myself and not notice.
(I don't use a dull blade since it's not efficient, but I'll use one if nothing else is available.)
If it is gene based, I'm not sure if it's something that moderates pain tolerance, hair / keratin composition, or some combination. I can grow a really thick beard, fwiw.
Open comb double edge razor lets the blade to reach hair without bending them as much. I'm not sure if it's that or something else, but double edge razors are less irritating than anything else for me.
You could use two different blades for the different tasks?
> An in-situ hair cutting experiment in a scanning electron microscope, showing the chipping process. Image: Gianluca Roscioli
That video was oddly pleasant to watch. I admit I was expecting to see the blade become miraculously f'd up in the process, due to the rest of the article, but hair is indeed very soft and the look of that angular cut at such a scale is kind of amazing to think about.
(Perhaps when such microscopes hit Aliexpress we'll see this genre enter the extremely-satisfying-videos arena)
That video was oddly pleasant to watch. I admit I was expecting to see the blade become miraculously f'd up in the process, due to the rest of the article, but hair is indeed very soft and the look of that angular cut at such a scale is kind of amazing to think about.
(Perhaps when such microscopes hit Aliexpress we'll see this genre enter the extremely-satisfying-videos arena)
It took a moment to realise it but given the scanning nature of the microscope this was actually done like a stop motion animation…
That or scanning electron microscopes have gotten a way faster “shutter speed” since I last looked at them.
That or scanning electron microscopes have gotten a way faster “shutter speed” since I last looked at them.
Looks like we're seeing basically a recording of what you'd see at the microscope, just not in real time. The video is way sped up.
It is not in manufacturers' interest to apply this information toward a longer lasting blade. Replacing them is the business model.
It's quite simple to sharpen your own razors or shaving blades, I've been doing it for years.
Sure, but you're a user, not a manufacturer. ;-)
how?
Even rubbing against a pair of jeans will sharpen them again.
https://imustacheyoutoshave.com/sharpening-a-razor-with-your...
https://imustacheyoutoshave.com/sharpening-a-razor-with-your...
I tried this and had very little success.
I just switched to a double edge safety razor and never looked back.
I just switched to a double edge safety razor and never looked back.
nice leather strop?
Stropping is not sharpening. Stropping is just bending the edge back into shape when it rolls onto itself. Sharpening involves removing material which is necessary when you have chipping like mentioned in the article.
Stropping is sharpening. A clean strop (without added abrasive) not only straightens the edge, but also burnishes it and removes material by abrasion. Here are some electron microscope images showing the effects.
https://scienceofsharp.com/2014/08/13/what-does-stropping-do...
https://scienceofsharp.com/2014/08/13/what-does-stropping-do...
Discussed at the time:
Why shaving dulls even the sharpest of razors - https://news.ycombinator.com/item?id=24075855 - Aug 2020 (123 comments)
Why shaving dulls even the sharpest of razors - https://news.ycombinator.com/item?id=24075855 - Aug 2020 (123 comments)
I've read a ton about razors in the past decade or so, and wish more of what has been reported was covered here. This just reports that hairs microchip blades. To what extent does it matter, for example?
Firstly, I'd read that DE blades actually get sharper after the first shave, due to coating wearing off, then quickly dull after the third or fourth shave. Personally, I'm unsure of this finding, as I always find new blades the best cutting and in fact change my blade every other shave.
Secondly, it's commonplace to the point of common knowledge or folk lore that it is rusting that ruins blades, hence you should soak them in alcohol, or dry them vigorously after each shave. Is this even true?
Firstly, I'd read that DE blades actually get sharper after the first shave, due to coating wearing off, then quickly dull after the third or fourth shave. Personally, I'm unsure of this finding, as I always find new blades the best cutting and in fact change my blade every other shave.
Secondly, it's commonplace to the point of common knowledge or folk lore that it is rusting that ruins blades, hence you should soak them in alcohol, or dry them vigorously after each shave. Is this even true?
Nah, there's no need to alcohol/dry DE blades. They're all made of stainless steel nowadays and don't rust. That advice was maybe from 100 years ago when they were made of carbon steel. You're more likely to dull the blade by accidentally hitting something with its edge (hopefully not your finger) if you take it out of the razor.
As for changing every other shave, I guess it depends on beard and razor. I have a Merkur 34C that tugs like mad whatever blade I use, new, old, in-between, they're all as bad. And an Ikon slant thing that feels like you could use a piece of paper in it and it'd work wonderfully. I go about 60-70 shaves before I can tell the razor might be getting a bit dull in that one.
As for changing every other shave, I guess it depends on beard and razor. I have a Merkur 34C that tugs like mad whatever blade I use, new, old, in-between, they're all as bad. And an Ikon slant thing that feels like you could use a piece of paper in it and it'd work wonderfully. I go about 60-70 shaves before I can tell the razor might be getting a bit dull in that one.
Feather ASD2. I have extremely thick face hairs, like little wires. Which I find odd, because my head hair and arm hair and such are very fair, thin, soft. It's also a different color...blond vs some copper color(now half gray).
With a new blade, it feels like rubbing a wand on my face. By the 4th shave, it feels like a tiny metal man is plucking each hair from my face. Especially painful in the mustache area.
With a new blade, it feels like rubbing a wand on my face. By the 4th shave, it feels like a tiny metal man is plucking each hair from my face. Especially painful in the mustache area.
I feel your pain, I think I get a reliable 1-2 shaves from a new blade before wanting to change it. My neck pays the price if I don't.
[deleted]
I've been using a RazorPit sharpener for years - the thing really works!! And I consume a couple of blades a year, if that.
With kitchen knives, acid in fruits, esp, is the main reason they grow dull. Rinse 'em immediately after, without fail.
Skin oils might be a bit of harm, too.
Skin oils might be a bit of harm, too.
Source? And is this effect more serious than hitting the hardwood underneath the fruit? And the chipping explained in this article?
I always assumed razor blades were designed to last as short as possible a time that people would tolerate so as to maximize recurring revenue.
All cutting edges have in common that the sharper you make them, the more quickly they'll dull. It's why kitchen knives get sharpened at a shallower angle than hunting knives, and those shallower than hatchets and such.
Razors have a much, much tinier edge than even the sharpest filet knife. So basically every cut deforms the edge in someway.
They could potentially make thicker blades, but most people aren't going to ever bother resharpening them, nor would they be able to get the edge correct. And if they make the edge itself thicker... it's going to feel like shaving with an axe.
Razors have a much, much tinier edge than even the sharpest filet knife. So basically every cut deforms the edge in someway.
They could potentially make thicker blades, but most people aren't going to ever bother resharpening them, nor would they be able to get the edge correct. And if they make the edge itself thicker... it's going to feel like shaving with an axe.
More acute angles resist abrasive wear better because more material must be removed before the edge radius is too large to cut effectively. More obtuse angles resist deformation and chipping better, but cannot slice through material as effectively.
https://knifesteelnerds.com/2018/06/18/maximizing-edge-reten...
https://knifesteelnerds.com/2018/06/18/maximizing-edge-reten...
For this purpose it's difficult to make blades that are both sharp, and dull quickly.
Razor blades are a standardised commodity. And it's easy to switch suppliers.
This explains why my shaving blade last for me very long time - I always shave in the opposite direction of hair growth, not along, so that blade always approaches hair at nearly 90 degrees.
if you shave along the direction of hair growth, the blade will approach hair at 15-30 degrees which causes excess wear & tear on a shaving blade.
if you shave along the direction of hair growth, the blade will approach hair at 15-30 degrees which causes excess wear & tear on a shaving blade.
Another tip that has worked for me is stropping the blade by running it backwards on the skin of my arm. It’s anecdote but it certainly seems to give me several more shaves out of the blade. I generally start when I would otherwise throw the blade out.
I do this against a towel after each shave, I saw a video some 10-15 years ago of a guy doing it against jeans. I believe he also verified with a microscope it indeed made the blade sharper.
I saw something similar. I thought it was Hank Green in a vlogbrothers video. My
Google-fu isn't good enough to find it again.
One warning though, shaving against the grain can increase razor burn and ingrown hairs.
I thought everyone did that?
I always go with the grain for the first pass and against the grain for the second.
Me too; my hair is coarse. But I'm too chicken to go against the grain with a straight razor. So I keep a Gilette Mach 3 for the second pass. I get a "baby's bottom" result. I wish I had the guts to try against-the-grain with a straight razor. I have tried across-the-grain for the second pass, with disappointing results.
That does seem to be the most common method. Starting out by going against the grain is just uncomfortable for me. Fine for the second pass though, although I usually go perpendicular to the direction of growth then.
people with extra thick facial hair have problems cutting against the grain.
if blade is not extra sharp, blade starts ripping hair, shaving along the grain in comparison is more forgiving for duller blades.
if blade is not extra sharp, blade starts ripping hair, shaving along the grain in comparison is more forgiving for duller blades.
I'd take my skin off if I did that on the first pass.
I do first pass with the grain, second against
its supposed to irritate the skin more or smth but i do it anyway and don't have problems
Interesting article! However I hoped to get some recommendations, or at least “it doesn’t matter what you buy”, and maybe some comments on the performance of multi-blade razors.
Given that the angle of cut matters is it better to shave certain parts of the face with the grain or against?
Given that the angle of cut matters is it better to shave certain parts of the face with the grain or against?
I prefer to use double edge safety razors and shaving with the grain. It prevents ingrown hairs, but the result is slightly less smooth. It's enough for daily use and very comfortable while shaving. Replacing blades is super cheap so it's always sharp.
always against, so that blade approaches hair as close to 90 degrees as possible, cuts quickly and is done.
what really kills the blade and creates cracks is when you cut hair at 15-20 degrees and blade cuts hair and then starts dragging it along your face while cutting and this is how microcracks form and grow in size.
you can create your own experiment with knife and some veggie like green onion. try to cut it at steep angle and drag it along the cutting board - and you will see that it produces much more stress on cutting surface
what really kills the blade and creates cracks is when you cut hair at 15-20 degrees and blade cuts hair and then starts dragging it along your face while cutting and this is how microcracks form and grow in size.
you can create your own experiment with knife and some veggie like green onion. try to cut it at steep angle and drag it along the cutting board - and you will see that it produces much more stress on cutting surface
Item 1. I hate sharpening knives and tools, so I wish someone would do a similar study for wood plane irons/blades (including their different steel types) versus various grinding techniques, grinding grit sizes etc.; and also explain why good old carbon steel often gives a smoother cut than do many of the harder specialized steels that have Rockwell figures which are well into the 60s—even though the fact that carbon steel dulls and blunts much more quickly than do those much harder steels?
Item 2. In a somewhat oblique vein, during COVID I always wore N95/P2 masks in public and I always took extra heed to follow the instructions that came with them which read to the effect that 'this mask will be less effective on those with bearded faces'.
Clearly that stands to reason so the question is by how much.
I'm constantly bemused by the large percentage masks on bearded faces and whose wearers seem oblivious to the fact that their beards are likely rendering their masks ineffective. Especially so when I see doctors on TV who've beards and who are there specifically to proselytize the virtues of wearing masks. With their beards popping out from behind their ill-fitting masks, it seems strange to me that these highly trained medicos seem oblivious to the obvious fact that their beards are putting them at risk—not to mention that they are setting a bad example.
Now the issue is this: given that a clean-shaven, stubble-free face provides a better mask-to-skin seal than one with stubble, the questions are:
Does anyone know of whether tests have been done on N95-type masks to test the effectiveness of their mask-to-skin seals? If so, whether any significant leakage was detected at the seal and whether stubble growth throughout the day worsened said leakage (the implication being that by the afternoon/evening masks would be less effective though increasing seal leakage)?
The corollary of the question would be to ask if a beard stubble impedes the effectiveness of the mask-to-skin seal then at what point in the growth of a newly-forming beard (at what stubble length, etc.) does the stubble render the mask ineffective (dangerous to wear)?
Item 2. In a somewhat oblique vein, during COVID I always wore N95/P2 masks in public and I always took extra heed to follow the instructions that came with them which read to the effect that 'this mask will be less effective on those with bearded faces'.
Clearly that stands to reason so the question is by how much.
I'm constantly bemused by the large percentage masks on bearded faces and whose wearers seem oblivious to the fact that their beards are likely rendering their masks ineffective. Especially so when I see doctors on TV who've beards and who are there specifically to proselytize the virtues of wearing masks. With their beards popping out from behind their ill-fitting masks, it seems strange to me that these highly trained medicos seem oblivious to the obvious fact that their beards are putting them at risk—not to mention that they are setting a bad example.
Now the issue is this: given that a clean-shaven, stubble-free face provides a better mask-to-skin seal than one with stubble, the questions are:
Does anyone know of whether tests have been done on N95-type masks to test the effectiveness of their mask-to-skin seals? If so, whether any significant leakage was detected at the seal and whether stubble growth throughout the day worsened said leakage (the implication being that by the afternoon/evening masks would be less effective though increasing seal leakage)?
The corollary of the question would be to ask if a beard stubble impedes the effectiveness of the mask-to-skin seal then at what point in the growth of a newly-forming beard (at what stubble length, etc.) does the stubble render the mask ineffective (dangerous to wear)?
>>I wish someone would do a similar study for wood plane irons/blades (including their different steel types) versus various grinding techniques,
I think you're looking for the book "Knife Deburring: Science behind the lasting razor edge" by Vadim Kralchuk. The author had a good website, but it appears no more and my cursory web search indicates that he has passed away. He has / had a YouTube channel as well.
I think you're looking for the book "Knife Deburring: Science behind the lasting razor edge" by Vadim Kralchuk. The author had a good website, but it appears no more and my cursory web search indicates that he has passed away. He has / had a YouTube channel as well.
Thanks, I'll also keep an eye out for it.
I'm not bad at sharpening plane irons and when I set my mind to it I can make them razor sharp—certainly sharp enough to shave with but I only test them by shaving the hairs on my arm and they do that very well.
That said, most books on this subject only cover techniques and not the underlying metallurgy. The metallurgy is important but the problem that most of us encounter is that we plane users don't know what it is (as it's usually unspecified).
Even if it is, it doesn't help much. Leaving aside badly-tempered steel (sharpened to red heat on a grinder etc.), some steels are just horrible to work with, I've some block plane blades made in the 1930s that have high tungsten content and they're almost impossible to sharpen well and even when razor sharp they don't cut well and it's never been clear why. Thus my comment about wanting to know more about the subject.
I'm not bad at sharpening plane irons and when I set my mind to it I can make them razor sharp—certainly sharp enough to shave with but I only test them by shaving the hairs on my arm and they do that very well.
That said, most books on this subject only cover techniques and not the underlying metallurgy. The metallurgy is important but the problem that most of us encounter is that we plane users don't know what it is (as it's usually unspecified).
Even if it is, it doesn't help much. Leaving aside badly-tempered steel (sharpened to red heat on a grinder etc.), some steels are just horrible to work with, I've some block plane blades made in the 1930s that have high tungsten content and they're almost impossible to sharpen well and even when razor sharp they don't cut well and it's never been clear why. Thus my comment about wanting to know more about the subject.
A big part of the aforementioned book is the manner in which differing steels produce a burr, or even micro-burr that can be mistaken for an edge, but cuts poorly and/or deteriorates quickly. A number of deburring techniques are tested on a number of steels and it is noteworthy that there is no single best method - each category of steels responds best to a different manner of deburring. Great longevity was achieved with proper deburring (as shown in the book with a host of SEM photos.
Excellent (aftermarket) plane irons of known alloy are widely available (at least here in the U.S.). I know some woodworkers value having all original parts, but if the primary goal is paper-thin even-width shavings it's hard to beat modern metallurgy.
Excellent (aftermarket) plane irons of known alloy are widely available (at least here in the U.S.). I know some woodworkers value having all original parts, but if the primary goal is paper-thin even-width shavings it's hard to beat modern metallurgy.
That's interesting, especially if it has info on ways of identifying steels where micro-burrs really aren't very controllable. One does everything correctly (I even use a lab microscope occasionally) and with some steels micro-burrs sort of flake off irrespective of the method of sharpening and or steeling them.
Some steels are just horrible and tempering and hardness are not necessarily good indicators of quality. I have a few chisels that superficially seem OK and the steel is hard and takes a good edge but five minutes later they're useless, others, sometimes even cheaper ones, turn out to be excellent.
As a techie who like playing with tech toys I thought of using a handheld x-ray fluorescence spectrometers like, say, this one: https://alloytester.com/xrf-steel-tester. There are any number of them around these days but they're expensive even to hire and I can't really justify one just to indulge my curiosity. However though, it would be really nice to go around testing everything that has an edge and logging its alloy properties against actual performance tests. Perhaps some day.
I couldn't care less about original parts (they're tools!)—so long as the tool works well (I don't for a moment consider myself a collector of old tools). That said, when making repairs I'll go to some trouble with old tools to match a tool with its 'correct' parts if possible (but ultimately it's a pragmatic decision—if I don't have the correct part I'll use wherever is to hand or what works best). By that I mean if it's possible to mate together a tool with parts from the same manufacturing source and same era then I'll do. For example, my No. 8 Stanley somehow lost it's lever cap during a move and I had access to several others that would fit but I selected one that came from the same factory and manufactured around the same time (in this instance the plane was of US manufacture/New Britain and made in 1933, so it received another lever cap from the same factory made in the same era (it was of the first generation to use the kidney-shaped slot for the cap's screw). I'm in Australia, so I had lever caps manufactured in the US, UK and here (including UK Record parts) to choose from. Nevertheless, it now has a plane iron of modern manufacture (but I've kept the original one and it's identified as belonging to said plane). There's also another reason to match parts which is that they usually fit better (leaving Bed Rock planes aside, I'm also of the opinion that the best consistent run of 'normal production' planes Stanley ever made came from its US plant and were manufactured between 1933 and about 1941 (the run came to an end when war regulations kiboshed the quality).
I do have a sense of history when it comes to these old hand-tools, my No. 8 is now 89 years old but it's not the oldest, that accolade goes to my No. 45† which dates from 1907. I'm of the opinion that we never actually own these objects, we're just their custodians for life—after all, my No. 8 is still in excellent condition (so are several others which are older), and if looked after with a little care, it'll still have several human lifetimes left in it after I'm gone. BTW, its original owner wrote his name on a piece of paper and dated it then put it in the space under the plane's tote (I'm now very curious to know who he was but I've really no idea). Anyway, that piece of paper stays with the plane (I've really no right to remove it).
Incidentally, I have a copy of Antique & Collectable Stanley Tools - A Guide to Identity & Value - 1996 edition by John Walker. You're likely already aware of it but in case you're not, it's an absolutely invaluable 880-plus page tome on the subject of Stanley tools, there's nothing else its equal. It's the ultimate bible for not only collectors but also for anyone who fixes or refurbishes these tools. There's a new edition out which I've not yet seen (it was out of print for quite some years which made secondhand copies of it much more valuable than many of the tools mentioned therein).
Back to plane irons, I use this mob from time to time for replacement irons but they're expensive here where I live. They are reasonably consistent and work reasonably well but I'm not altogether totally happy with them (it's what I now use in the No. 8, No. 4, 5 etc.): https://www.ibctools.ca/product-category/ibc-blades/. They'll also do paper-thin shavings but that's usually of secondary importance—for me, a steel that keeps a keen edge for the longest duration ranks first (these come close but I've had irons that cut somewhat better).
Thanks for your comment.
__
† Damn monstrosity of a thing it is, the only thing I can imagine that's worse would be a No. 55.
Some steels are just horrible and tempering and hardness are not necessarily good indicators of quality. I have a few chisels that superficially seem OK and the steel is hard and takes a good edge but five minutes later they're useless, others, sometimes even cheaper ones, turn out to be excellent.
As a techie who like playing with tech toys I thought of using a handheld x-ray fluorescence spectrometers like, say, this one: https://alloytester.com/xrf-steel-tester. There are any number of them around these days but they're expensive even to hire and I can't really justify one just to indulge my curiosity. However though, it would be really nice to go around testing everything that has an edge and logging its alloy properties against actual performance tests. Perhaps some day.
I couldn't care less about original parts (they're tools!)—so long as the tool works well (I don't for a moment consider myself a collector of old tools). That said, when making repairs I'll go to some trouble with old tools to match a tool with its 'correct' parts if possible (but ultimately it's a pragmatic decision—if I don't have the correct part I'll use wherever is to hand or what works best). By that I mean if it's possible to mate together a tool with parts from the same manufacturing source and same era then I'll do. For example, my No. 8 Stanley somehow lost it's lever cap during a move and I had access to several others that would fit but I selected one that came from the same factory and manufactured around the same time (in this instance the plane was of US manufacture/New Britain and made in 1933, so it received another lever cap from the same factory made in the same era (it was of the first generation to use the kidney-shaped slot for the cap's screw). I'm in Australia, so I had lever caps manufactured in the US, UK and here (including UK Record parts) to choose from. Nevertheless, it now has a plane iron of modern manufacture (but I've kept the original one and it's identified as belonging to said plane). There's also another reason to match parts which is that they usually fit better (leaving Bed Rock planes aside, I'm also of the opinion that the best consistent run of 'normal production' planes Stanley ever made came from its US plant and were manufactured between 1933 and about 1941 (the run came to an end when war regulations kiboshed the quality).
I do have a sense of history when it comes to these old hand-tools, my No. 8 is now 89 years old but it's not the oldest, that accolade goes to my No. 45† which dates from 1907. I'm of the opinion that we never actually own these objects, we're just their custodians for life—after all, my No. 8 is still in excellent condition (so are several others which are older), and if looked after with a little care, it'll still have several human lifetimes left in it after I'm gone. BTW, its original owner wrote his name on a piece of paper and dated it then put it in the space under the plane's tote (I'm now very curious to know who he was but I've really no idea). Anyway, that piece of paper stays with the plane (I've really no right to remove it).
Incidentally, I have a copy of Antique & Collectable Stanley Tools - A Guide to Identity & Value - 1996 edition by John Walker. You're likely already aware of it but in case you're not, it's an absolutely invaluable 880-plus page tome on the subject of Stanley tools, there's nothing else its equal. It's the ultimate bible for not only collectors but also for anyone who fixes or refurbishes these tools. There's a new edition out which I've not yet seen (it was out of print for quite some years which made secondhand copies of it much more valuable than many of the tools mentioned therein).
Back to plane irons, I use this mob from time to time for replacement irons but they're expensive here where I live. They are reasonably consistent and work reasonably well but I'm not altogether totally happy with them (it's what I now use in the No. 8, No. 4, 5 etc.): https://www.ibctools.ca/product-category/ibc-blades/. They'll also do paper-thin shavings but that's usually of secondary importance—for me, a steel that keeps a keen edge for the longest duration ranks first (these come close but I've had irons that cut somewhat better).
Thanks for your comment.
__
† Damn monstrosity of a thing it is, the only thing I can imagine that's worse would be a No. 55.
Not sure where you can do it outside the industry, but mask fit tests are required in many (all?) US petrochemical facilities. The test involves an accurate measurement of gases passing through to the mask wearer.
Edit: seems you can just buy a kit https://pksafety.com/3m-ft-20-training-and-fit-testing-kit-i...
Yeah, I'm vaguely aware of this and mask fitting for asbestos removal is almost mandatory in many workplaces.
I suppose, given all the fuss over COVID, I've been rather surprised by casualness over the approach to mask-wearing given that the warning were there on mask packets before the pandemic. I would have thought this would have alerted many to the fact come COVID but seemingly not.
BTW, my attention to detail seems to have paid off so far (I've not caught the disease as yet). Nevertheless, it would have been good to have been able to put some some figures to the practice rather than working anecdotally.
I suppose, given all the fuss over COVID, I've been rather surprised by casualness over the approach to mask-wearing given that the warning were there on mask packets before the pandemic. I would have thought this would have alerted many to the fact come COVID but seemingly not.
BTW, my attention to detail seems to have paid off so far (I've not caught the disease as yet). Nevertheless, it would have been good to have been able to put some some figures to the practice rather than working anecdotally.
A little off-topic, but:
Am I the only one who finds the repeated incorrect spelling of "heterogeneous" annoying?
The worst part is, the way they spell it, "heterogenous", actually means something else. Just not what they think it means...
Am I the only one who finds the repeated incorrect spelling of "heterogeneous" annoying?
The worst part is, the way they spell it, "heterogenous", actually means something else. Just not what they think it means...
"Heterogeneous" is just so horrifically awkward-sounding. It's as if it's a word purpose-built for making the speaker sound like they're pronouncing a word they don't know how to pronounce.
I read a lengthy article on how the edge of a straight razor reacts to being used.
It seems that microscopically, the honed edge of the blade looks like a comb of teeth. When you shave, these teeth fold over. Stropping apparently straightens out the folded edge.
Eventually these teeth break off, and the edge has to be remade. That can be done with a few strokes on a coticule, every 6 months or so.
The authors apparently experimented on stainless steel blades; stright razors are made from carbon steel, which doubtless has a different microcrystalline structure.
[I know, the article's about disposable razors]
It seems that microscopically, the honed edge of the blade looks like a comb of teeth. When you shave, these teeth fold over. Stropping apparently straightens out the folded edge.
Eventually these teeth break off, and the edge has to be remade. That can be done with a few strokes on a coticule, every 6 months or so.
The authors apparently experimented on stainless steel blades; stright razors are made from carbon steel, which doubtless has a different microcrystalline structure.
[I know, the article's about disposable razors]
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That headline suggests a sharper razor should dull less. But surely the sharper a blade is (the thinner the edge) the faster it will dull.
I've noticed that a lot of the alloys for knife blades that have good edge retention are from PM (often, but not exclusively, sintered). I always assumed it was because of the types of alloys they could make, but this article suggests that the uniformity attainable through PM might be a bigger effect.
Yeah, I was wondering about the particle metallurgy process (or the equivalent from other foundries). I know that AEB-L and similar Sandvik steels are ingot steels. Would the added cost be worth it? What about something LC200N (Cronidur 30)? Great corrosion resistance and toughness. Comments here talk about corrosion leading to micro fractures. Not sure if traditional toughness in terms of cutlery applies here.
Now does stropping straighten or correct the imperfections caused as we believe or is it a useless practice? We’ve been doing it for hundreds of years with this mental model that these experiments confirm and that stropping doesn’t sharpen but merely straightens the edge.
Yet one must still sharpen the edge eventually.
Yet one must still sharpen the edge eventually.
The purpose of stropping is to break off the weak edge formed after sharpening so the smoothed edge is less prone to chipping.
So what if you made a razor blade of something like the monocrystaline nickel alloy used to make jet turbine blades? Would they never dull from cutting soft material such as hair?
Some discussion from when this was news 2 years ago:
https://news.ycombinator.com/item?id=24075855
https://news.ycombinator.com/item?id=24075855
Turns out everything is just fuzzy magnets sticking together softly.
> “The team’s findings may also offer clues on how to preserve a blade’s sharpness.”
This team is playing with fire and should tread carefully. If they should happen to stumble across the secret to a “perma-sharp” razor blade that never needs replacing, I have no doubt that “big razor” will dispatch them with a vengeance.
The team lead will be strolling through the park on a lazy Sunday afternoon, when a stunningly beautiful female jogger “accidentally” steps on his foot. He’ll think nothing of it, but what he won’t realize is that he was just on the receiving end of a Polonium 238 injection delivered at the order of the Gillette family.
This team is playing with fire and should tread carefully. If they should happen to stumble across the secret to a “perma-sharp” razor blade that never needs replacing, I have no doubt that “big razor” will dispatch them with a vengeance.
The team lead will be strolling through the park on a lazy Sunday afternoon, when a stunningly beautiful female jogger “accidentally” steps on his foot. He’ll think nothing of it, but what he won’t realize is that he was just on the receiving end of a Polonium 238 injection delivered at the order of the Gillette family.
With all of human tech and science, why do we not have better hair management by now?
Growth, removal, color…
You’d think the richest people would want to invest in that research as they grow older.
Growth, removal, color…
You’d think the richest people would want to invest in that research as they grow older.
We do have IPL (https://en.wikipedia.org/wiki/Intense_pulsed_light) to stop growing hair where it's problematic.
We have hair transplants, not really a new thig.
For some woman washing hair is a hours long procedure applying various chemicals :)
Coloring is also "solved" a long time ago.
What do you miss?
We have hair transplants, not really a new thig.
For some woman washing hair is a hours long procedure applying various chemicals :)
Coloring is also "solved" a long time ago.
What do you miss?
I believe, even with all the impressive advances, we do not know as much as we would like to think.
True, most of the supposed impressive advances touted by the media, including that of medicine amount to almost nothing on close examination.
TL;DR:
"They found that the simulations predicted failure under three conditions: when the blade approached the hair at an angle, when the blade’s steel was heterogenous in composition, and when the edge of a hair strand met the blade at a weak point in its heterogenous structure."
"Tasan says these conditions illustrate a mechanism known as stress intensification, in which the effect of a stress applied to a material is intensified if the material’s structure has microcracks. Once an initial microcrack forms, the material’s heterogeneous structure enabled these cracks to easily grow to chips."
"They found that the simulations predicted failure under three conditions: when the blade approached the hair at an angle, when the blade’s steel was heterogenous in composition, and when the edge of a hair strand met the blade at a weak point in its heterogenous structure."
"Tasan says these conditions illustrate a mechanism known as stress intensification, in which the effect of a stress applied to a material is intensified if the material’s structure has microcracks. Once an initial microcrack forms, the material’s heterogeneous structure enabled these cracks to easily grow to chips."
How did this article get the first word "How" through the HN filter? Why does this filter exist?
1) The filter only exists for the initial submission. You can manually edit the leading word back in after that if you want.
2) I'm not certain, but I presume the idea is that many clickbait article titles are improved by removing the "how".
2) I'm not certain, but I presume the idea is that many clickbait article titles are improved by removing the "how".
Ceramic knifes are much better at cutting soft stuff than metal knifes.
So why are there no ceramic blade razors?
So why are there no ceramic blade razors?
I guess it's mostly just not economical to produce such a thing. As other commenters noted, with good quality disposable safety blades you get between 3 and 10 shaves depending on your hair and preference. When you buy those in a typical bulk package containing 20 cartons of 5 blades each, your yearly expense in terms of blades sits around the €5 point.
Perhaps Gillette could put out one of their fancy twenty-odd blade monstrosities with an extra ceramic blade in front though. I'm sure that's marketable to people who haven't figured out they're spending way too much money on something that costs a fraction if you look beyond the products pharmacies push in your face.
Perhaps Gillette could put out one of their fancy twenty-odd blade monstrosities with an extra ceramic blade in front though. I'm sure that's marketable to people who haven't figured out they're spending way too much money on something that costs a fraction if you look beyond the products pharmacies push in your face.
Ceramic knives are so prone to chipping that they effectively have micro-serrated edges even when freshly sharpened. A micro-serrated edge on a razor pulls hairs and cuts skin.
I don't doubt that in your experience ceramic knives cut food better than metal ones, but I suspect you have not used a well-sharpened knife. Mass-produced knives are typically sharpened using belt grinders and do not cut as effectively as knives hand-sharpened by someone skilled at it.
https://scienceofsharp.com/2018/02/24/ceramic-blades/
I don't doubt that in your experience ceramic knives cut food better than metal ones, but I suspect you have not used a well-sharpened knife. Mass-produced knives are typically sharpened using belt grinders and do not cut as effectively as knives hand-sharpened by someone skilled at it.
https://scienceofsharp.com/2018/02/24/ceramic-blades/
I use Feather blades from Japan. I can get up to six shaves from a single two-sided blade.
I've used Kai blades and they're far too sharp. Nowadays I much prefer Voskhod blades, they're much better fitted to my hair and skin.
I've found Astra blades to be good enough for me; quite a step up from the lowest tier (e.g., Bic), but not as fancy as those Japanese blades.
Inflation certainly seems like a good motivator for more people to switch to safety blades — wet shaving should be cheap, and it is if one stops buying the stuff marketed the hardest.
Inflation certainly seems like a good motivator for more people to switch to safety blades — wet shaving should be cheap, and it is if one stops buying the stuff marketed the hardest.
I initially switched years ago because it made more financial sense, but nowadays I just enjoy safety blades more. I don't spend much on blades (10€ for a hundred Voskhod blades lasts me ages), but I do spend a bit on the shaving cream (nothing beats L'Occitane's shaving cream, and it's a local company).
The sharpest blade is not necessarily the best. The "perfect" blade, should such a thing exist, depends on your razor, beard and technique.
Shameless plug: should you start the search for the perfect blade, at https://www.razorbladesclub.com/ you'll find the widest selection of double edge razor blades worldwide.
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The razor housing can make a big difference to this as well. I find feathers are far too sharp for me in one of my razors but are excellent in another, while astra blades are perfect in the first one and too dull in the second.
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Mildly OT, but the hair cutting gifs are surprisingly satisfying to watch :)
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They make ceramic knives. Why not ceramic razors?