Six years ago I decided to start using an old-fashioned (“double edged”) safety razor.
I got a couple of “blade samplers” from Amazon — collections of maybe a dozen different brands, five blades from each brand. I then bought a 100-count box of Persona blades. They got good reviews and, at that time, they were made in Virginia.
Sometime this year, I’ll probably have to buy razor blades again. So, obviously, we’re not talking about a huge per-diem expenditure, for shaving. Nevertheless, whatever I buy this time, I’m going to end up living with it for years. So I’ve been revisiting the market for double-edge razor blades. And, incidentally, disposable razors.
How much?
Just to set some parameters, based on what’s offered on Amazon.
A typical name-brand mid-level disposable razor costs about $1 each. Plus or minus. There seems to be an extremely wide choice of brands and styles around that price point. The price seems unrelated to whether or not the handle is re-usable. The very upper end of what I observe on Amazon seems to run around $2 each. Maybe a bit more. Those models tend to have a lot of blades (e.g., five-blade cartridges).
On Amazon, at least, three brands — Schick, Bic, and Gillette — account for the overwhelming majority of offerings.
Cheap disposable razors bought in bulk can cost as little as 12 cents each, but a more typical price is around 20 cents each. Most of the bulk disposable offerings are no-name razors, but Bic also offers a low-end single-blade disposable for roughly 20 cents each, in bulk.
By contrast, there are dozens of brands of double-edged razor blades offered on Amazon. Compared to just three name brands of disposable razors. I counted 25 different brands among the first 64 products shown on Amazon.
Several name-brand blades can be had for six or seven cents a blade (Dorco, Wilkinson, Derby). You have your pick of blades in the 10-to-20-cent range. The very top end (Feather, an extremely sharp Japanese-made blade) runs about 40 cents each. (Those prices are all for lots of 100 blades).
Of course, you can find variation after variation. Exotic metal coatings. Lubricating strips. Multiple blades. Pivoting heads. And so on.
How long?
But where this market really gets somewhat crazy is when people state how long they will use a single disposable razor or razor blade.
For razor blades, almost all comments on Amazon fall into a range that I’d call reasonable. A handful of guys use each blade just once. Most seem to report between three and five shaves per blade. This means that, for the typical user, those low-end blades end up costing just over a penny a shave.
For disposable shavers, though, I note two things. First, the median number of shaves appears to be higher. I’d say that seven shaves per razor is the most frequently mentioned number. And, invariably, if you read enough comments on Amazon, you’ll find people who claim to use a single disposable razor for an almost unbelievably long time. It’s not at all unusual to see claims that one razor will last half a year or even longer.
Arguably, part of that is simple economics. When, exactly, you decide to replace your razor blade is subjective. And, plausibly, the more each blade costs, the longer you try to keep using it. So I would not be surprised to see people using a $1 disposable razor somewhat longer than they would use a 6-cent disposable blade. But nothing explains the guys who buy and use one razor a year.
This one simple trick changes everything!
Once blade longevity comes up, people will begin listing all the tricks they use to make razor blades last longer. Or, at least, that they believe make razor blades last longer.
As with the estimates of blade longevity above, these are also all over the map. And I have yet to see even one objective analysis of this topic. No testing of any sort, as far as I can tell.
Above, you see a list that I made after a brief internet search. These are all the methods I saw for increasing the life span of a disposable razor or blade. I have no clue whether or how well any of them work.
Let me try to explain my skepticism.
The most commonly-cited advice is to dry the blade off after each use. That seems perfectly reasonable, I guess, as rust will dull a blade. Until you realize that almost all razor blades are made from stainless steel. Which, last time I checked, by definition, does not rust. So why would drying it well extend the life?
This is not completely true. Stainless needs exposure to oxygen to keep the surface “passivated”. If you put it in an oxygen-starved environment, some types of stainless will rust. This is why stainless is typically not recommended for use well below the waterline of a boat (reference). Once you’re a few feet under water, you may be in a sufficiently oxygen-poor environment that stainless will rust.
And just when you’ve started to shrug your shoulders about that one, you’ll come across a guy who swears he can make a single disposable razor last a year merely by drying it off with a towel after each use (reference).
That one simple trick changes everything about wear-and-tear on a razor’s edge? Really? I dry my blades off after each use, and I might get five shaves per blade.
Another common suggestion is to strop the blade, that is, do a fine sharpening of the edge by running the blade “backwards” (not in the shaving direction) over some suitable material. At first glance, that seems completely plausible, as stropping is the traditional last step in sharpening a straight razor. And then you’ll find somebody who swears that simply running the razor down his (denim) jeans a few times this makes his disposable razors last for months (reference). Others say to strop the blade against the back of your arm.
Or, you can buy a commercially-made razor strop on Amazon (reference). Most of these commercial strops promise a 10-fold or better increase in the life of your blade. (And, if you keep looking, you will eventually run across various antique devices for sharpening razor blades — so the idea of resharpening razor blades is not new.)
In terms of science, this study out of MIT found that razor blades wear out by a process of fracturing and chipping at the edge, as they cut through hair. The blades did not get “rounder” at the edge, as a kitchen knife will. Instead, they got “rougher”, accumulating myriad small chips and cracks. If that’s all there is to it, it seems like (e.g.) drying off the blade shouldn’t do much. But stropping it plausibly might restore a more even cutting edge.
Is it possible to test these methods objectively?
On the one hand, sure, it is a little crazy to test a method for extending the life of a 10-cent razor blade. Or a 20-cent disposable razor.
On the other hand, it’s not like anybody else is stepping up to do it.
I need two things: A reliable way to test sharpness, and a realistic way to dull blades.
Sharpness tester on the cheap. There are such things as edge sharpness testers. But even the cheapest one I can find on Amazon will set me back a few hundred dollars. Which seems like a rather extreme expenditure to help me figure out how to extend the life of a ten-cent razor blade.
It looks like the most common sharpness tester measures the force required to cut through a very thin wire or string. Surely I can gin something up out of scraps that will do the same thing with a reasonable degree of repeatability.
As with commercial testers, I’ll suspend a thread under a known tension. Attach the razor blade to some weight. Put the blade in contact with the thread. And slowly increase the weight until the thread parts.
But instead of using some sort of instant-reading scale, I’m going to pivot the entire assembly in an arc so that an increasing amount of weight will bear on the razor, on the thread. Start with the arm vertical, and slowly rotate it. Stop when the razor severs the thread. The bigger the angle, the more weight it took, and the duller the razor is. I won’t be able to calibrate this against a standard tester, but (with a bit of geometry) this will give me an accurate relative comparison across blades.
Artificial beard? The other barrier to doing this test is the lack of a standard way to dull the edge of the razor. If I literally have to shave with each blade, then a) the test is going to take forever, and b) that will introduce variation because I can’t guarantee that I’ll shave the same way each day.
As of this writing, though, I’m really not seeing the alternative. If the dulling process occurs as described by MIT above, I really can’t just (e.g.) slice up bits of paper or something. (Though I may resort to that.) Ideally, I’d have to slice through human hair, and lots of it.
Conclusion
Ever since I went back to shaving with a safety razor, I have wondered about the advice you will see on extending the life of your razor blades. Now that I’m getting ready to buy some — this year — I’m going to work up some sort of objective test, of at least some of those suggestions.
Of all the suggestions, I think I’ll test stropping the blade first. For one thing, given what I think I know about what blades are made of and how they wear, that would seem to make the most sense. Second, the claims made by sellers of commercial razor strops are quite extreme. Seems like, if they can make those claims with a straight face, and if those are true, I ought to be able to observe some effect. Finally, I can take existing used blades and see if stropping restores sharpness, using a piece of denim as the strop. But first I need to rig up that sharpness tester.
