At its core a straight razor is a specialized knife. The physics of a straight razor are the same. There are two reasons a knife or scissors cuts: simple pushing force and shear stress. Both are at work when we shave.

Shear stress is at work when you use a scissors to cut through paper. The two blades move past each other forcing the medium being cut to tear. Putting it simply, the hairs can only withstand so much force. A scissors works by holding the hair in place and applying force to shear off the hair being removed. See this page on shearing action for more information and an animation visualizing this concept.

The other physics acting upon our hairs is a simple pushing force. A blade cuts because the edge is extremely small. In the case of a straight razor, .5 microns or smaller. This small edge is then pushed into the hair. The hair, being softer than hardened steel, yields first. The physics is simple: force is magnified if concentrated in a small area. The stress acting upon the hairs is directly proportional to the force being applied and inversely proportional to the surface area. In plainer terms, the hairs will be cut easier if you use more pressure/force and a sharper razor.

So, applying the physics to our shaving regimens, we can have a better understanding of the physics of our shave. The pushing action is generated from the physics of the razor being pushed through the hairs. The hairs, being of a much softer substance, give way easily. But not before the hairs bend and pull. The pushing force is generated by our hands and is directly proportional to our skill level with the straight razor. The shearing action is enacted upon the razor through the skin and the razor blade acting in conjunction with the hair. While not a perfect shearing action, the skin acts as the second force acting upon the hairs. In our case, the skin and hair follicles hold the hair in place while the razor blade slices through the hair.

Check out this time warp clip to see how these forces act upon our faces in slow motion.

As you can see, the razor doesn’t magically cut through the hairs. The razor first meets resistance, the skin is pulled, then when the hairs can stand no more, the razor slices through the hair being cut and moves on to the next hair. This resistance is what causes pulling.

The basic physics law at work is Newton’s second law.

F=MA

In practical terms, the force behind the razor is controlled by how fast and hard we move the razor across our faces. Thus, to achieve maximum cutting force, we should strive to move the blade faster. In reality, the speed of the blade is absolutely restricted by the user’s skill and the threat of cutting into the skin. Put another way: move the razor too fast and your going to look chop up your face.

The other fact we can deduce from this formula is that a heavier razor will cut more effectively than a lighter razor. This is why wedge type razors are perceived to be better than hollow ground razors by some users. This also explains why 8/8″ razors are perceived to cut better. They are also popular the sheer size of the razor is desirable in itself to some users and collectors.

Back to the molecular level. We all know a sharper razor will cut through hairs more efficiently than a dull razor. This is because of the physics of pressure. Concentrating the force into a smaller area increases the level of force acting upon the hairs. The formula is below:

As you can see, the pressure exerted upon the hair increases as the edge radius decreases. Since reducing the edge radius decreases the surface area in contact with the hair, the force imparted upon the hair is magnified exponentially. However, the razor can only cut as well as the person handling the razor. We can decrease the edge radius to as small as possible, but ultimately, the F component is the key. If the user only uses 50% of their potential, the hair is only being cut half as effectively.

Looking at how razor dulling affects the forces exerted upon the hairs, we have to first define razor dulling. Razor dulling on the molecular level would be an increase in the edge radius (the thickness of the edge where 0 edge radius is a perfect razor). The above formula shows that a 10% increase in edge radius imparts a loss of 9.09% of the pressure acting upon the hairs. A 50% increase in edge radius results in a loss of 1/3 of the pressure. As you can see, the skill of the user is vastly more important than the sharpness of the razor.

So, to sum it all up: The sharper the razor, the greater the impact upon your shaving skill. However, the forces imparted by you are vastly more important than how sharp the razor is.

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According to this new blog post by John Tischler, Going Green by Shaving Straight, straight shaving is the cheaper than DE shaving! Now, everyone knew that straight razor + hone = set for life if you don’t break the razor. But Mr. Tischler’s math proves that DE’s are more expensive than straights even if you use a hone-meister! The math is in the article, however, he doesn’t state how many times you have to re-hone per year. We recommend once every 180 days of use. Of course, it’s only $10 per hone if you use our re-honing service. But I’m getting off-track. The point is, straight razor shaving is the cheapest means of shaving; even if you use a honemeister to sharpen & hone your razor for you!

Further savings can be had if you buy a vintage straight razor. There is no advantage to buying a modern razor as opposed to a restored vintage razor or one in great shape. You also don’t need a fancy strop. Any piece of good quality leather will suffice. Finally, you should be shaving with a brush and soap anyway, so these shouldn’t be additional costs. Finally, buying your own hone may be cheaper in the long run, but in the short term it is actually not cost effective. You need to buy an expensive finishing stone rated at least 12,000 grit; 16,000+ is better. But more importantly, you must invest a lot of time into learning how to hone. Even more time than you invested learning how to straight shave. At $100 for a finishing stone, you could purchase five year’s worth of professional honing.

Either way you go, the proof is in the numbers. Straight shaving is the cheapest way to shave!

Unfortunately, there is no one answer to this problem. A straight razor should not need honing for a long time. Provided you properly strop after each use, it should be between six months to a year in between honing. However, when you first start, the razor will invariably dull quicker and need re-sharpening. In the beginning, three to four months of good shaves is actually a good starting point. One month is not unheard of and re-honing your razor is just something that needs to be done as you journey down the long road toward straight shaving nirvana. Below I have compiled a list of the five most likely causes and their solutions.

1. Poor stropping technique – This is actually quite common among new straight razor users. The cause is rolling the edge. By dragging the edge perpendicular or near to perpendicular from the strop, you will roll the edge. The good news is this is 100% fixable through proper stropping technique. This why stropping is so important. Click here to read our article about stropping!
2. Rust – Rust is the enemy of sharp. Sadly the only cure to rust is to re-hone/sharpen the razor. Rust happens naturally, but there are certain things that can increase the rust rate: not drying the razor completely, storing it in the bathroom, or living in a humid climate. The good news is that there are things you can do to retard rust formation. Oil the blade when not in use, strop on a dry towel after use, stropping on linen/cotton, storing the razor somewhere dry, wrapping the razor in wax paper & place it in a waterproof box, etc..
3. High Angle – The higher the angle you shave your hairs with, the quicker your razor will dull. The solution is to lower the angle. This is hard for new straight razor users to accomplish because increasing the angle makes it a little easier to get a closer shave, but at the cost of edge longevity. In addition, increasing the razor’s angle helps compensate for a razor in need of honing. Thus, it becomes a vicious downward spiral; the only real solution is to sharpen/hone the razor if you are stuck in this vicious circle.
4. Coarse Hair – Sadly there is nothing we can do about this. Some men’s beards are so coarse that they just eat up razors. If this is the problem, it really doesn’t matter terribly much how well honed/sharpened the straight razor was to begin with, your coarse beard will just dull it. But don’t despair! There are things you can do. Soaking your beard softens the hairs and allows for easier cutting. Using a pre-shave lotion that soaks the hairs further softens the hairs, making it easier to shave. Proper stretching also helps, along with doing two with the grain passes.
5. Never sharp – The sharper your razor starts off at, the sharper it will be several months later. A good honing will pay dividends in the end.

1. Shave More – Getting a good shave using a straight razor requires a certain feel that you will develop over time. Unfortunately, some things only come with experience. You don’t have to shave your face, you can practice on your arm, a tomato, or just in the air.
2. Use Both Hands – Ambidexterity is good. Using both hands allows you to get better angles and reach places easier. Specifically, it allows an easier ATG on the opposite side of your face.
3. Soak Your Beard – This is incredibly important. Hair is made of keratin. Keratin is extremely tough. To make it easier for your razor to cut your hairs, you need to soak your beard in water. Hair absorbs water and makes the otherwise tough and somewhat brittle hairs pliable and water logged. Don’t believe us, feel your hair before and after you wash you shower.
4. Stretch the Skin – Skin stretching is extremely important for straight razor shaving. Always stretch in the opposite direction of the blade.U
5. Use a Good Soap and Quality Brush –If you still use canned shaving cream, you have to switch to soap and brush. It’s just vastly superior. Straight razors prefer slick lather. Old fashioned glycerin soap is slicker than the canned goop, and tallow soap is slicker than glycerin soap. Unless you’re averse to animal killing, you should make the switch.
6. Lower the Angle – Your razor is not a magical laser. If you angle the razor down towards your skin, your razor is just going to cut your skin. If you angle the edge just so, towards the base of the hairs, your razor will glide over your skin and give you a great shave.
7. Take Your Time – This cannot be emphasized enough. Too many cuts and poor shaving experiences are due to rushing into the task with gusto. Straight razor shaving is something to be taken very seriously and enjoyed. It should be a relaxing experience. Take your time, learn the right techniques, shave in short strokes until you master the straight razor and the angles.
8. Re-Wet Your Lather – There is no rule or reason to let the lather on your face dry out without replenishing it. If the lather on your face is not rinsing off your razor with no residue, dip your brush in water and re-lather on your face.
9. Use Less Pressure – Your not using a cartridge, there is no safety on your straight razor. More importantly, your straight razor is ACTUALLY SHARP!!! Yes, for the first time in your life, your actually shaving with something that is truly razor sharp and if you don’t treat it with respect, it will bite you. Unlike cartridges, the straight razor actually shaves by cutting the hairs, not by pulling them out or tearing up your face. If you choose to add pressure, you will only take off skin. Okay, this is not meant to say don’t use any pressure at all, but you have to learn exactly how much pressure is necessary. Go slowly and stop adding pressure once the razor cuts cleanly.
10. Use Water Only – As mentioned above, straight razors like slick lather. Water is not only really slick, but it is transparent. Shaving with water allows you to see everything.
11. Use a Sharp Razor – This one is a no brainer, but is a common enough problem that I must mention it. A sharper razor cuts the hairs easier and closer. Just watch the Gillette commercials. If you try everything else on this list and your razor still tugs, have someone else hone your straight razor. A professional honing may be what is required.

1. Heating the Water

The absolute fastest way to get hot water in the morning is to own a hot water pot. The next fastest way to get really hot water is to use the microwave. Fill up a  ceramic bowl with water and microwave for ~ 1:15 on high; adjust for personal preference and water amount. Alternatively, you could wait for the hot water from your tap. However, we prefer the first two methods because you can use filtered water.

2. Stropping

There are two ways to save time in the morning. One is to strop the night before. The second is to strop while your water is being heated. We like the microwave method because it gives us a full minute and odd seconds to strop. We also like stropping on the linen/cotton after the shave. More on this in the forthcoming stropping article.

3. Soaking the Beard & Brush

Your brush needs to soak. So does your beard. Might as well get the two out of the way at the same time. Once the water has been heated, drop your brush in the bowl and wash your face/take a shower. You could also wrap your face in a hot towel. The hot towel is quite nice, but you might feel like going back to sleep if you do that.

4. Lathering

Face lathering is quicker than lathering in a bowl, and canned shaving cream is even quicker. However, there is only so far we are willing to go to save time. Cream might be even quicker, but until they invent tallow cream, we prefer our tallow soap.

5. The Actual Shave

Only experience can cut down the time here. Skipping the XTG pass will cut down on the time. While it is possible to go straight to ATG, it isn’t as pleasant. If you move deftly and lather quickly, the actual shave can be cut down to five minutes or so.

There you have it. Our time saving tips. What are yours?