Hot Tip For My Blog Followers - Buy On Our Website & Pay Less Than On eBay

As a courtesy to our blog followers, we are pricing most of our Premium Diamond Slurries LESS on our website than on our eBay store.  Same product. Same shipping times. Lower prices.

A Hard Particle Is Good To Find: The Diamond Vs. CBN Debate

It is a truism of marketing that when a market-space starts becoming crowded with product, someone is bound to come out with something they claim to be "New & Improved" to attempt to capture greater market share.  You are seeing this happen right now in the razor and knife honing market.  There are quite a few products on the market, including ours, which utilize diamonds as the primary abrasive to perfect your blades.  With the market becoming crowded with various brands of diamond sprays, each using different formulas and quantities of those magic microscopic gems, at least one clever vendor has come out with something new - CBN.

Actually CBN isn't exactly new.  In fact, it has been around since the 1970's.  But what you probably want to know is if it offers any real advantages over the tried and true diamond slurries.  That is the question that this short article will answer. 

It might be useful to start out with a basic knowledge of the stuff. CBN, or Cubic Boron Nitride is a laboratory manufactured material which has the same crystalline structure as diamond.  It is 2nd only to diamond in hardness, which makes it harder than all known metals.

But does it have an advantage over diamond slurries?  Surprisingly it has two, but there is a caveat to this statement, so please read to the end.

In situations with large amounts of friction, diamond, which is nearly 100% carbon, can form an affinity for the carbon in the steel.  This can cause the diamond particles to break down and lose their effectiveness.  This problem does not occur with CBN.  Secondly, diamond suffers from a massive loss in hardness when it gets hot, making it effectively softer than CBN under these conditions.

Sound like a problem, doesn't it?  So how hot does the material have to get to give CBN the advantage?  Pretty toasty, as it turns out.  The metal would have to achieve a temperature of 700 degrees Celsius (1,292 degrees Fahrenheit) for the performance of diamonds to degrade to an effectiveness below that of CBN.  I don't know how many "X" strokes I can do on a hone or strop in one minute, but I believe that I have a very long way to go before I am going fast enough to generate 1,292 degrees of heat.  Of course, by then my strop would have long since caught fire :-)

Yes, I have taken a moment to poke a bit of fun at the issue, but there is a serious point here.  You, the consumer, are being presented with an ever-increasing array of choices.  This is both a blessing and a curse.  You can get some excellent values and you can also get mislead.  There is no evidence to demonstrate that, all things being equal, CBN cuts faster or in any way performs better than diamond....unless you are working at those very high temperatures or very high levels of friction which create them. You needn't take my word for it; research it for yourself.  Any decent article on the advantages of CBN over diamond will mention heat/friction as the primary factor in its superiority.

That said, I would expect the performance of CBN slurry spray to be no worse than that of diamond sprays - although at $32.95* per 2 oz bottle of CBN vs. $14.95 for the most expensive of our Premium Diamond Slurry Sprays, the price may give you pause.

As I have said countless times - the only way to find what work for you is to try the product.  That is one of the reasons that we keep our prices affordable and you, our prospective customer, armed with the facts.



*Source: chefsknivestogo.com

A Good "Look" At Diamond Slurry Sprays - Avoiding The Deception of Appearances

Gaining an in-depth understanding of superabrasives, including natural and synthetic diamonds, involves years of experience and education well beyond that possessed by the average reader. And it can be somewhat overwhelming to the prospective buyer when they are peppered with Scanning Electron Microscope photos and the output of the myriad other equipment used in the SA chemist's lab - all as proof that a particular seller's product is the best. One could dive deeply into this rich pool of images and data and be lost for weeks.

In this article, however, I wanted to get away from these highly technical arguments for buying these products and discuss something that anyone looking at these products can see just by looking at the bottle. 

When I receive my slurries from the chemist, they are delivered in large clear glass bottles.  Long ago when I first started testing slurry formulas to find the ones that were most effective, I left several of these bottles on the shelf for a couple of weeks when I went away on vacation. When I return to the untouched bottles, I found, to my horror, (particularly in the cases of the 1 and 2 micron formulations) that the liquid in the bottles was crystal clear, with just the smallest amount of off-white powder glazing the bottom!  It looked to me as if there was almost no diamond at all in the formula.  After all, I could see hefty piles of white powder sitting at the bottom of the bottles of my future competitor's products, so I certainly expected to see a similar amount of this magic dust in mine. As I had paid dearly for these slurries, I immediately phoned the chemist who proceeded to further my "education" on superabrasives.

As I have written before, microns are extremely tiny things.  The period at the end of this sentence is 400 to 600 microns across.  This makes a particle the size of one or two microns not only invisible to the naked eye, but also invisible to a powerful light microscope.  In fact, an expensive Electron Microscope called an SEM is needed to see these very small abrasive particles. The chemist, who had over 20 years of experience working with superabrasives, reminded me that, given their size, these tiny particles cannot be seen by visually inspecting a bottle of them in solution.  "The white powder at the bottom of the bottles you saw," he told me, "was another substance or mixture of substances.  Without having a bottle of these products to inspect, I can't tell you what they are, but I CAN tell you what they aren't - diamonds."  He went on to say that there were undoubtedly some diamond particles mixed in with the white stuff, but not necessarily any more than were anywhere else in the bottle. 

This was an important part of my education in superabrasives and I thought I would pass it along to those of you who are thinking of buying these products. When you are considering diamond slurries, your eyes will tell you little to nothing about the contents of the bottle.  The information reminded me of something that Obi Wan Kenobi said to Luke Skywalker when teaching him the ways of the Force: "Your eyes can deceive you; don't trust them."  It is a good rule of thumb to follow when evaluating diamond slurries.

As I have said it many other pieces on this subject, there is one test and one test alone that counts - using the product.  So if you are interested in really keen blades, I'm afraid you are going to have to buy 'em and try 'em.  I recommend ours. They are up to 35% less expensive than competitive products and they work. Use the product for a full 7 days.  If you aren't satisfied, return the sealed bottle containing the unused portion of the slurry and receive a FULL refund*.  If you have any questions before buying, including which product(s) will work best for you, email us at info@littlestropper.com.


*Refunds made only for products returned with tamper-evident neck seal intact and no other signs of tampering. Refund offer is restricted to ONE bottle of any of our Premium Diamond Slurry Products, one time only. S&H charges cannot be refunded. Refunds will not be made to competitors buying our products for testing or to commercial buyers - in other words, you must be a legitimate consumer to qualify.

JUST RELEASED: Our NEW line of Premium Diamond Slurry Products.

Anyone who uses straight razors knows the value of a truly polished edge, which is as free as possible from imperfections and those nasty serrations. As someone who sharpens razors professionally, I know it can take a lot of time and effort to get a razor in a condition where it is fit to shave with - old wedges can be particularly troublesome. But once I'm done and have sent the shave-ready razor to a customer. I want him to be able to use it for many months without having to send it back to me for rehoning. So I took the system that I created for my own razor finishing practice and made it accessible and easy to use for the average shaver. Best of all, this system doesn't require investing in expensive hones and it doesn't require a lot of room. It is easy to use and it doesn't make a mess. It is our patent pending blade finishing system - the Magnetic StropBox and our NEW Premium Diamond Slurry Sprays..

The Magnetic StropBox System pairs up a box with one magnetic side with a two types of tops (called StropTops) that adhere to it - top bovine leather and 100% hard wool felt. Of particular interest to the razor user is the hard wool felt StropTop. These soft but tough tops are the perfect surfaces on which to use our exclusive line of Premium Diamond Slurry Sprays, available in 2 Micron 1 Micron, .50 Micron and .25 Micron. Just spray the felt lightly and strop your edge to perfection. How far you want to go down in grit is up to you. 2 Microns in the equivalent of an 11,000 grit stone. Some folks will be fine with that. I like to go all the way down to 1/4 Micron for the smoothest possible shave. It's the finish that I use for my razor customers and the one I use for myself. Of course, I finish up with leather before shaving. With my handy StropBox and StropTops, I no longer have to stand in the bathroom to strop razors. And the tops are so cheap that I don't have to kick myself if I cut one.

The system also works for pocket knives, kitchen knives and tools.

If you want to keep your razors performing at their best and your knives and tools at their sharpest, you MUST check out our products TODAY!

You can buy any of our StropBox items or Slurry Sprays at http://www.littlestropper.com/store

ANNOUNCEMENT: NEw Line of Diamond Slurry Sprays & Lubricant Released Ahread Of Schedule

Our line of Premium Diamond Slurry Sprays & Our Exclusive SlurryLube Lubricanf & Extender will be available ahead of schedule.  These products make it fast and easy to maintain perfect edges on straight razors, knives and tools! Bottles of 1 Micron and .50 Micron SMD Formulas are shipping IMMEDIATELY.  All other products will ship by January 7th.  But supplies are fairly short, so get YOURS now!  Don't risk being on backorder!

Questions?  eMail us at info@littlestropper.com

Diamond Slurry Sprays, Lubricity & Particle Characteristics: How To Put The Ultimate Edge On Razors, Knives & Tools

Diamond Slurry Sprays, Lubricity & Particle Characteristics:

How To Put The Ultimate Edge On Razors, Knives & Tools

By John H. Tischler

Friday, December 24, 2010

Introduction

While I’m sure that you all understand the concept of friction, many of you probably are unfamiliar with the term “lubricity.”  Lubricity is defined in the Merriam-Webster dictionary as: the capacity for reducing friction. You can also think of it as the ability of a lubricant (i.e. oil, water, Teflon, etc.) to reduce friction between two objects.  Just for your information, the study of lubricity is part of the larger science of Tribology – the study of interacting surfaces in relative motion.  While this information may be very interesting to some and boring to others, it’s critical for anyone who wishes to truly understand blade sharpening and polishing.  So if you belong to this determined group, or wish to, read on.

Lubricity & The Pursuit Of The Perfect Edge

Since the pursuit of the perfectly keen blade is our agenda here, let’s apply the principles of lubricity to the honing and stropping of fine blades.  Assume we have a flat surface covered with a liquid containing particles that are harder than steel.  Let us further assume that we are moving a steel blade over that surface, using just the weight of the blade itself for downward pressure.  As the lubricity of the liquid increases, the friction between the abrasive surface, and the steel contacting that surface, decreases.  This decrease in friction reduces the ability of the abrasive to remove metal.  The degree to which an abrasive removes material is often referred to as the “cutting power” of the abrasive.  

Since cutting power is what we all want from our abrasive surfaces, we should always want to keep lubricity to a minimum, right?  Well, that depends.  Have you ever tried honing a blade on a dry waterstone?  How about on a dry DMT diamond plate?  If you have, you have already experienced the effects of very low lubricity – quite a bit of metal is removed (not always where you want it to be) and the stone or plate is soon clogged with worn metal fragments.  This makes the abrasive surface an inconsistent cutter – leaving some spots that will cut harshly and others where cutting power is virtually non-existent.  Further, this lack of lubricity also makes for a very rough edge – something you can see under a microscope and, certainly, feel against your skin.  

The Role Of Lubricants In Creating Better Edges

It is for these reasons that we generally use a lubricant (something which increases lubricity) when we are honing.  Lubricants reduce the friction between the abrasive and the blade – reducing cutting power, but producing a more consistent “cut” and a smoother edge.  The lubricant also helps to carry away the metal (and “spent” abrasive particles) removed by the abrasive in action, helping to prevent the “clogging” of the honing or stropping surface which occurs when the surface is too dry.  Lastly, using a lubricant extends the service life of an abrasive’s surface.

Proper lubrication is most important when you are using an abrasive that is considerably harder than the piece you are attempting to sharpen or polish – and they don’t come any harder than diamond.  Diamonds, natural or synthetic, are the hardest substance on earth.  Hardness isn’t the same thing as toughness – you could take a hammer and easily smash an engagement ring (PLEASE don’t try this at home); it just means that, when moved against a softer material (which is everything else on earth other than another diamond) with sufficient pressure, the diamond will cut into that material and remove some of it.  The depth and shape of this cut, and the amount of material removed, are all impacted by the shape of the diamond, the pressure applied to the workpiece against the diamond and, last but not least, the lubricity of the solution standing between it and the softer material.

Water is the most common and least expensive lubricant.  It also has extremely low lubricity and viscosity (a measure of the resistance of a fluid under stress, often known as “thickness”) – which is one of the reasons why it’s not used to lubricate the moving parts in car and truck engines.  It does, however, have qualities that are very desirable when honing a razor, fine knife or tool.  It is plentiful and inexpensive, is easily cleaned up and does a fair job of carrying away worn metal and spent abrasive, ensuring a more consistent “cut” and extending the life of abrasive materials.  It also aids in producing a less jagged edge than you would otherwise produce using a dry surface, although not nearly as smooth as one would get with a superior lubricant.

The Princess And The Pea – How Something Very Small Can Be Very Irritating

Even though it is the main topic of this paper, I am going to leave the subject of lubricity for a little while to talk about abrasive particles on the micron and particularly the sub-micron levels.  You will have to trust me that this short diversion is important and that I will return to the topic in a few paragraphs.  Firstly let us quickly try to wrap our brains around the concept of the micron-sized particle.  To put microns in perspective, you may wish to consider that the period at the end of this sentence is approximately 400 microns across; and that one micron is equal to about 1/300^th the diameter of a human hair strand.  Sub-micron level particles are obviously even smaller – so small, in fact that Electron Microscopes are required to see them.

Despite this miniscule size, there is a common complaint about slurries which utilize diamonds smaller than one micron in size – that they leave an edge that is too harsh or “toothy.”  This seems somewhat counter-intuitive when dealing with particles so tiny, but it’s true.  This effect leads many honemeisters (persons skilled in the art of creating perfect edges) to use chromium oxide (a substance which is softer than diamond) pasted strops after using diamond slurry sprays to “soften” the edge.  The reasoning often runs something like this: “Diamonds are a harder substance and thus will cut deeper and rougher scratches than will chromium oxide, therefore honing on chromium oxide is necessary to ‘smooth’ the edge.”   This is only partially correct and is typically a result of using the wrong type of diamond in the wrong way.  

Synthetic Monocrystalline Diamonds (SMD)

Most diamond slurry formulations sold for sharpening fine blades rely on synthetic monocrystalline diamonds (SMD) as the abrasive.  

Popular for their extremely low cost and high durability, SMD diamond slurries are an excellent choice for earlier stage material removal, but have some inherent problems that make them a poor choice for final finishing work.  These problems include, first and foremost, the shape of the particle itself.  It is “blocky” with very sharp, but very few cutting edges.  SMD slurries also suffer from problems with particle shape, such as the existence of needle-like “slivers” and long and flat “plate structures.”  These “strays,“ which often get past even the highest quality Particle Size Distribution (PSD) testing equipment and procedures, lead to SMD’s relatively high “scratch rate” – tiny bits of damage to the blade’s sub-surface.  These scratches are not visible through magnification under a normal microscope (you would need an Electron Microscope to see them), but they can be perceived on an edge that is used for shaving as “harshness.”  

For these reasons, SMD diamond slurries are not the first choice of manufacturers needing to produce the finest finishes.  They are also why I do not recommend the use of SMD diamonds in sub-micron level slurries used for final finishing/polishing.  While it is beyond the scope of this paper to delve deeply into the subject of diamond morphology, I felt that I have to mention it I have read claims by leading competitors that monocrystalline diamonds are more appropriate for finishing because they will leave a less “toothy edge” than polycrystalline diamonds.  It is well known that, in fact, the opposite is true.

Synthetic Polycrystalline Diamonds (SPD)

Synthetic polycrystalline diamonds (SPD) share many attributes of their monocrystalline cousins (particularly hardness), but their structure – formed by a controlled detonation of high explosives, is very different.  Each tiny SPD particle contains even smaller “microcrystallites” whose numerous planes are pointed in different crystallographic directions every 10 to 50 nanometers (a measure significantly smaller than microns) – regardless of the particle size distribution of the parent particle. The hardness of each individual microcrystallite can be compared with that of synthetic monocrystalline diamond. Due to the greater number of cutting edges and greater surface area simultaneously contacting the workpiece, SPD-based slurries remove more metal than SMD slurries and are much less likely to cause subsurface damage to the metal ^±. But all of these good qualities come at a price – with polycrystalline diamonds costing much more than monocrystalline preparations. 

Lubricity Revisited

Earlier in this paper, I described the characteristic problems of using abrasives with little or no lubricant – inconsistent cutting, harsh cutting and clogging of the abrasive surface.  Considering what we have learned about the “stray” particles in SMD slurries, is it any wonder that these problems would be compounded by using a solution with very low lubricity – particularly when you are using particles with an inherent tendency to “gouge?”  Does scratching not worsen in an absence of lubrication?

Most diamond slurry sprays, such as the ones produced by current market leaders, use carriers (the solution in which the abrasive particles are suspended) with very low lubricity – depending primarily on de-ionized water to reduce friction.  You can see this in the way these product atomize (disperse in a spray) – producing an extremely fine mist, much like tap water (A bit too fine, in my opinion.  At a distance from the strop of 5”, one of these products produced a rough circle 8” in diameter – leaving more slurry on the table than on the strop.  Sprayed closer, the slurry is too “concentrated” in one spot.).  They also tend to dry quite quickly on a 100% hard wool felt strop – also an indication of a primary dependence on water as a lubricant.  You can also feel the almost complete absence of viscosity in the “draw” or friction perceived when stropping a blade against a hard wool felt strop treated with these products.  And since it they are often used dry, that friction is enhanced – at least until the abraded metal starts clogging the surface.  

So after I strop a razor on hard wool felt sprayed with products of this type, used wet or dry, I do find that stropping on chromium oxide is necessary before use – as the blade coming off a strop sprayed with it does tend to leave a harsh edge.  If you are working with knives, you probably want a harsher edge – especially at sub-micron levels, as the microscopic scratches may produce better cutting action – you just might want to pay less for it.  

How To Get The Ultimate Edge For Less Money

We have customers all over the world looking to put the best possible edges on razors, knives and fine tools.  In response to these needs, Little Stropper^TM has formulated products that use the less expensive synthetic monocrystalline diamonds in our 1 and 2 micron slurries (where a higher scratch rate matters less and may even be desirable), and the more costly synthetic polycrystalline diamonds (SPD) in our .50 micron and .25 micron slurries.   Since the sub-micron level slurries tend to be used for finishing and polishing, we felt that using synthetic polycrystalline diamonds, with their much lower scratch rates, was worth the extra expense.  Additionally In all of our formulations, we use significantly higher levels of water-soluble lubricants than you will find in the leading brands. So you will feel less friction when using our products, but you will get a better and smoother edge.  You will also use less of the product, as we add special ingredients designed to keep the stropping surface moist for long periods of time.

Another thing you will appreciate is our prices. Even our SPD formulations, which utilize a much more expensive diamond than do our SMD products, are priced lower than the leading brand.  Depending on the formulation used, our products ounce-for-ounce cost up to 35% less than the current market leaders.  We are announcing the following products, which will be available for sale in January of 2011:

• 2.0 Micron Premium Synthetic Monocrystalline Diamond Slurry Spray (2 oz size)
• 1.0 Micron Premium Synthetic Monocrystalline Diamond Slurry Spray (2 oz size)
• .50 Micron Premium Synthetic Monocrystalline Diamond Slurry Spray (2 oz size)
• .50 Micron Premium Synthetic Polycrystalline Diamond Slurry Spray (2 oz size)
• .25 Micron Premium Synthetic Polycrystalline Diamond Slurry Spray (2 oz size)
• SlurryLube^TM – an economically priced diamond slurry extender and lubricant (2 oz size)

Beware Competitors Bearing Carats

A word to the wise – be wary of diamond slurry manufacturers that attempt to distract you from the price of their product by focusing on the number of carats of diamonds in the bottle.  “Stuffing” more and more diamond powder into a bottle of slurry, while certainly providing a rationale for charging a high price, is unlikely to improve the product’s performance.  The additional diamond particles just end up being wasted.  Our products are formulated with a focus on performance and results – not on carat weight.  So you end up paying for effectiveness, not powdered diamond.

Conclusion

I have used quite a bit of science and jargon in this paper – I do apologize for this and have tried to keep it to a minimum.  But most of you reading this (and thank you for coming this far with me) are not Tribologists.  You are folks who, like me, want a smooth close shave every day.  You want knives that will cut cleanly without slipping.  You want chisels and other bladed tools that will remove material reliably without “skipping” off surfaces or damaging your creations.  You also want to spend less time and money getting there.  

If any of the foregoing describes you, please try our Little Stropper^TM line of Premium Diamond Slurries and blade finishing products.  You will find them at www.littlestropper.com/store in January 2011.  If you have questions, please contact us at info@littlestropper.com.

John H. Tischler is President of Vintage Shaving Shoppe, LLC. and Little Stropper^TM brands.  He can be contacted at jtischler@littlestropper.com .

References:

± Tumavitch, Nicholas J., The Evolution of Diamond for Optical Component Finishing, Recent developments in the production of synthetic diamond abrasives have resulted in an array of varieties suitable for optical finishing applications., 2005.