Sometimes it’s OK to Have a Damn Good Strop!

In the ‘Razor Shark – Field Sharpening’ article, which I have renamed 'Razor S.H.A.R.K. Sharpening', mentioned above, I describe a simple, yet foolproof, methodology for sharpening any cutting edge on the planet. The system was developed by me over a number of years in response to the numerous difficulties many of my students were having whilst learning and practicing traditional sharpening techniques. The main problem most beginners seem to encounter, including myself, when I was still a sharpening neophyte, is that whilst the traditional theory of sharpening is relatively simple grasp, the practitioner is required to quickly develop a moderately high skill set, if they are to achieve any degree of sharpening success. In other words it seemed to me, when using traditional sharpening systems that the degree of blade sharpness that is usually attained is exponentially related to the level of skill that the practitioner has mastered at that point.

I reasoned that there ought to be a method, as yet unknown, of sharpening that required only the simplest of sharpening paraphernalia that could easily be taught, learned, mastered and then practiced and would give outstanding results from the outset. It had to be a system that would give professional results, would meet, or even exceed, most peeps expectations of blade sharpness and yet would satisfy even a fanatical cutting edge fusspot like me!

Given a smidgeon of practice, the techniques described in the article would enable most everyone to at least attain a level of sharpness that I refer to as ‘Chef Sharp’ i.e. sharp enough to easily and cleanly cut through a squishy tomato, which seems to be the iconic symbol of measuring blade sharpness.

Taking a blade that would be considered to be Chef Sharp, up to the next level of sharpness i.e. making it ‘Razor Sharp’, would be the subject of another article, since it would require a degree of explanation that would make it into a story in and of itself; hence this article.

To - laconically - describe the benefits of this article, yes I do know a few big words! I would say that Stropping is: ‘The final 1% of the sharpening process that makes 99% of the difference!’

I would strongly recommend that you read that article before this one, since it will give you a strong background into the Razor S.H.A.R.K. Sharpening technique as a whole. If you would like to read the 'Razor S.H.A.R.K. Sharpening' article frist please 'Click Here'. If you want to get straight into Stropping, let's get started!

In essence a Strop is a sharpening tool that used in the final or finishing step of blade sharpening. It is usually made from a soft material, such as paper or card, a soft wood such as balsa or fibreboard, or even from cloth; however leather is often considered the best material to use. Such materials are often stuck on to a flat, solid platform, or ‘Platen’, such as wood, glass or steel to name but a few that adds stability to the stropping material and the process of stropping, thereby allowing easier stropping to take place.

Since Strops are generally made from soft materials, they are, by design, not really intended to actually sharpen a blade’s cutting edge. Nevertheless, they can, at a pinch, be said to add to the sharpness to a blade - given that enough strokes, say 50 to 100 and up, on the Strop are made. However, I would say that the extra sharpness gained would be so insignificant as to be considered irrelevant to the finished results; bearing in mind what a Strop is usually made from, and then comparing it’s softness to the hardness of tempered steel. Certainly I have never really noticed any significant difference in all of the decades I have been sharpening and cutting.

Well, stropping is mainly used to realign a blade’s cutting edge, by straightening out any micro-rolls or distortions that occur when a blade is used. Also, stropping will clean the blade, wiping away debris that may have become stuck on the cutting edge itself, thereby reducing the cutting efficiency of that blade. It does not actually sharpen a dull blade. Want to know more about Sharpening your blades?

A Honing Strop, on the other hand, is a horse of different colour. A Honing Strop it is a standard Strop, preferably made from leather that has been coated, or ‘Loaded’ with an exceptionally fine abrasive. Thus, when a blade is repeatedly drawn, across a Honing Strop’s surface the addition of an abrasive will grind away metal from the blade, which is called ‘Honing’. Removal metal in this way effectively sharpens the blade; therefore, if no abrasive is present, it will not, because it effectively cannot!

In essence, all you have to do to turn a Strop into a Honing Strop is apply a small amount of a Honing Compound to its surface and voila, it becomes a Honing Strop. The impossi-difficulty lies in turning a Honing Strop back into a standard Strop, because once and abrasive has been applied the surface has effectively become contaminated – permanently! It is therefore important to think carefully before you commit!

The abrasives that are usually used on Honing Strops are called Honing Compounds. The most common Honing Compound abrasives are essentially made from superfine materials such as Aluminium Oxide, Carborandum, Silicon Carbide, Glass, Boron Carbide or even Diamond, to name but a few. These abrasives are so small that they are measured in microns (μm). A micron being one-thousandth of a millimetre (0.001mm) or 0.000039 of an inch; another way of categorising the particulate size of such abrasives is to refer to the ‘Grit’ size. The bigger the Grit size number, the smaller the actual size of the abrasive and therefore the finer it is. To give you some idea of scale, the thickness of the average human hair is about 75μm whilst the abrasive particle size of most Honing Compounds usually ranges from about 7μm or 2,800 Grit, to say 1μm or 14,000 Grit, the best size, in my opinion, being about 8,000 Grit or 3μm (microns) in size. Abrasives are mixed with a sticky(ish) carrying medium such as water based thickening agents, oils or waxes that allow an even coating of abrasive to be applied to the surface of a Strop. Applying a Honing Compound to a Strop is called ‘Loading’ the strop.

Hone Stopping, or simply Stropping, is done for two main reasons. The first reason, as already stated, is that Stropping is that last 1% of the sharpening process that adds 99% to the sharpness of a blade. The second reason is that it is an easy-peasy way of extending the life of a blade’s cutting edge - by a long way - before it needs to be re-sharpened on a whetstone again. A double ‘W B thank you mam!’ you might say.

As to the ‘When’ should a blade be stropped? Well that is hard to say, since it depends on a whole host of variable and factors. It is like asking the proverbial question, ‘How long is a piece of string?’ Suffice to say that it is an inalienable fact of life that whatever a blade is made from, however well it is made and then sharpened; it will eventually start to become dull. It is, therefore, my most ardent advice that at the very second you notice that your blade is failing to glide through the material that is being cut, at the very second when you notice that you are using that little bit of extra force to make a cut, it is time to give the blade a quick Strop. If done at this point the blade can ninety-nine times out of a hundred be brought back to its peak level of sharpness. More on how this is done later.

If, however, you leave it just a fraction of a minute longer, it may well past the point of no-return i.e. that critical point where you just can’t bring it back to its former glory and will, therefore, have to go through the whole sharpened process again from the beginning.

By way of explanation, let us say that the cutting edge of a blade, by virtue of it being made from metal, will always be somewhat softer than a Whetstone being made of … well Stone; so, a blade will always conform to the surface of a Whetstone. Conversely, a Strop, usually being made from a soft material such as leather being somewhat softer than the metal of a blade, will always conform to a blade’s cutting edge.

Since a Strop’s flexible soft surface, effectively wraps itself around a blade’s cutting edge, due to its elasticity, whilst the Honing Whetstone inflexible hard surface does not, Stropping a blade on a Strop, as opposed to a Whetstone, allows us to pay, markedly, less attention to blade stability and honing angle. This allows us to significantly increase the stropping speed, thereby saving us gobs of time, and effort to boot.

Having said this, here’s the ‘Rub’ that gives us pause; the very reason that makes the use of a Honing Strop so very fast and efficient, i.e. its flexibility and ability to conform to the cutting edge, is, ironically, the very same reason that prevents us from ever creating a ‘Scary Sharp’ cutting edge. To put it another way, the main disadvantage of using a Honing Strop over a Honing Whetstone, is the inability to ever achieve a ‘Scary Sharp’ cutting edge.

Try, if you will, pressing the tip of your finger gently into the muscle of your arm and then drag that finger down your arm, you will observe the way the skin on your arm flexes around the finger as the finger is moved. You will also observe that the skin on your arm does not suddenly flex, but is gently forced to conform to your finger, in a natural gentle curve like a ripple on a pond. It is the skin on your arm that gives to the point of your finger and not the other way around. If you now transmogrify your finger into a blade and your arm into a strop you will see, in your mind’s eye, how essentially a Strop works, albeit on a micro scale.

The best quality Strops are, in my opinion, made from leather, but not just any old leather! You should know by now that it is not that simple! Yes, Strops can be made from lots of other materials, but good old fashioned traditional leather is by far the best and most durable material to make Strops from.

If the very best stropping results are to be obtained whilst using a traditional Leather Strop, we need to take a look some of the finer qualities of the leather that is to be used. Leather quality, density, thickness and the tanning process used to make the leather are all very important considerations when either buying or making a Strop: -

• Leather Quality: - The quality of a piece of leather largely depends on the injuries that were inflicted upon the animal hide whilst the animal was still alive. Injuries can be created in any number of ways including branding, cuts that cause scarring, insect damage in the form of horse flies, warble fly larvae or ticks etc. Any form of damage that is carried over after the hide has been tanned will affects the quality of that hide, which will inevitably affect its value. Surface imperfections cannot usually used in a finished leather product and are therefore usually cut around and thrown away.
• Leather Density: - The density, and therefore the usefulness, to a leather smith, of a piece of leather, varies according to the location the leather was taken from on a hide. Leather that is cut from say the Butt (i.e. the animal’s lower back) is in much more demand, by leather smiths, than the leather that is cut from say the Belly of a hide. This is because Butt leather is much denser than Belly leather, making it considerably stronger, more resistant to tearing and therefore much more durable.
• Leather Thickness: - The thickness of a piece of leather has an enormous impact on the elasticity of that piece of leather. As we have already seen the elasticity of the leather can have a marked effect on a blade’s cutting edge life span due to ‘Opposed Compression Pushback’ abrasion. Ideally the leather used on a Strop should be about 3 to 4mm thick. If the leather is too thick or it is too soft (see Leather Density, above), for example, there may be too much ‘give’ in the Strop which will cause the blade to distort the Strop to a higher degree. On the other hand if the leather, on the Strop, is too thin it will not ‘give’ enough, which will require greater care, skill and concentration, whilst stropping, if Cutting Edge Platform stability is to be maintained. This will reduce the overall speed of stropping (See Honing Whetstone).
• The Tanning Process: - There are two main tanning methods usually employed to industrially tan animal hides. Vegetable (Veg) Tanning and Chromium Tanning. Veg Tanned leather, when processed correctly into Stropping Leather, has a very fine and smooth velvety surface sheen that is much finer than I have ever seen on Chromium Tanned leather. This velvet sheen, or ‘nap’ as it is usually called, can be seen on the surface of a new Strop as a change in the surface brightness when you gently sliding a finger over the surface. It is the calibre of this nap that is so important to us whilst stropping with my system, hence my emphasis on quality Veg Tanned leather.

Wiping a blade across a Strop’s surface that has been treated with a honing compound will cause a small amount of metal to be removed with each stroke. It is the build-up of this metal swarf mixing with the abrasive that quickly turns the surface of the Strop grey. The thicker this residue, the surface patina, becomes the darker it will appear, the darker appears the better the Strop will be for detecting microscopic cutting edge imperfections. So, the big bucks secret to successful stropping is all down to the Strops surface patina colour.

The last stage in the stropping process is also the ‘Maintenance’ stage in the stropping process; this is talked about in the ‘So why do we strop and when should it be done?’ section of this article. I usually refer to them as the ‘666 strops’, this is because it has wicked connotations and therefore makes a good tag to stick in the mind. Here’s how 666 strops are done: -

1. Place the blade onto the Strop as described in ‘Polishing the Blade’s Cutting Edge’ above.
2. Drag the cutting edge across the leather surface towards you, using light but firm pressure. If you see any lines appearing as the blade passes over the Strop, you will need to repeat the above, numbers 3 to 13 again until all you can see is a smooth slightly shiny Strop.
3. This time as you are moving the blade’s cutting edge along the surface of the Strop, try to swipe the entire length of the blade, from Heel to Point, across the Strops surface with each stroke.
4. Again, it is important to remember, if you don’t want to dull the blade’s cutting edge, that when you reach the end of each stroke, you consciously, and carefully, remove the blade from the Strop as if the blade were an airplane that is taking off from a runway.
5. At the end of the first stroke, move the blade back to the far end of the Strop, and repeat the procedure (numbers 14 to 18) another five times on this side of the blade - making a total of 6 strokes on this side of the blade.
6. Turn the blade over so that the cutting edge is now facing you and place it at the end of the Strop that is closest to you. Repeat numbers 14 to 18 on this side of the blade; remembering to apply the first two rules.
7. The next step is to complete a further six strokes - three strokes on each side of the blade - alternating one stroke per side until six full strokes have been completed. When this has been done the whole stropping process will have been completed and your blade should now be ‘Razor Hair Popping Sharp’ or as sharp as you can make it.

When the above steps have been completed your blade will be as sharp as you can get it at your current skill level, however, with practice the blade will become even sharper. Hopefully you will want to keep your blade in its peak condition for as long as possible; to this end it is important to judge the exact moment you need to give it another 666 Strops.

All things being equal the 666 strop will easily bring the blade back again, but remember to look for the tell tail signs of blade damage when you first begin to strop the blade and immediately repeat steps 3 to 20 if you spot them. If you ignore them, and continue to use the blade, you may well have to re-sharpen the blade from the very beginning again.

If your blade is not ‘Razor Hair Popping Sharp’ by this time then it will be for one of the following reasons: -

1. You missed something out of the Sharpening and Stropping process; therefore it is not my fault!
2. You made a mistake somewhere along the line; therefore it is not my fault!
3. You did everything correctly and just need a little more practice; therefore it is not my fault!
4. You did everything correctly and it is therefore my fault! In which case, I most humbly apologise and suggest that you read a, b and c again!

A Honing Strop is only ever used as ‘the finishing step in sharpening a blade’, it is, therefore, vitally important to remember that a Honing Strop cannot ever sharpen an already dull blade. If your blade’s cutting edge looks like a piece of round-bar and you strop it on a Honing Strop it will simply look like a well-polished piece of round-bar! It is essential that a blade’s cutting edge be as sharp as it can possibly be, before a Honing Strop is ever considered for use.

Please read my previous atricle 'Razor S.H.A.R.K. Sharpening' (Simplified Honing for Advanced Razor-sharp Knives), which demonstrates the simple principles, easily learned and mastered on how to simply and easily sharpen any Cutting Edge to a Razor Edge.

I have made several videos that demonstrate the system used in this article, which can be seen on our web site www.BeaverBushcraft.co.uk in ‘Videos and Articles’ under ‘Sharpening Videos by Mark Hordon’

Thanks for reading this article, and my previous one if you did so. If you have any questions I would be delighted to answer them for you, please send any questions to [email protected].