Posts Tagged ‘sharpening’

Jende Kangaroo and Leather Strops – What’s the difference?

October 17, 2016

We’ve recently introduced the Jende Kangaroo and Leather strops on color coded acrylic to our lineup. One of the questions that will inevitably be asked is “which one is better?” As usual, the answer is “it depends”. They are both excellent mediums, and this article is designed to allow you to make a better informed decision about which is better for you and your particular needs.

 

jende-leather-strop

Jende Leather Strop (acrylic side)

Kangaroo and Cow leathers are both tanned animal skins, In this case it is vegetable tanned, which is basically untreated with any oils, waxes, etc.. It’s the most natural foundation which can then be used as a clean, final strop or be loaded with pastes, sprays, compounds or emulsions of your choosing. Cow leather has a much longer history of use for stropping, with Kangaroo leather only becoming more accessible since Crocodile Dundee first appeared in the 1980s. 😀

jende-kangaroo-strop

Jende Kangaroo Strop (acrylic side)

Ounce for ounce, kangaroo has about 10 times the tensile strength as cow leather, meaning a thin 1mm strip of kangaroo is about as strong as a 2-3mm strip of cow leather. This translates into less compression of the kangaroo strop over the cow strop, which can be advantageous in certain situations like straight razor honing. But the compression of the cow leather can be more suitable to matching the shape of convex edges.

In order to better describe more of the differences between kangaroo and cow leather, we need to look more closely under the microscope. Here’s a side by side macro view of the Jende cow and kangaroo leathers. Pictures are taken with a Veho 400x and the actual resolution is 1.3mm wide x 1mm high.

 

cow-macro

Cow Leather, Macro

 

roo-macro

Kangaroo Leather, Macro

At this level, the cow leather looks very consistent and smooth. There is what’s best described as a “spotted” texture to the leather, but it seems flat, overall. (It reminds me of the surface of painted drywall, actually.) The Roo, however, looks like an army of ants are embedded in the surface. These are the hair follicles of the skin. Overall, the surface looks smooth, even with the contrast of the black follicles. Honestly, there’s not much difference to be seen between the two skins here.

Where things really change are at the micro level. This resolution is 1mm wide by 0.75mm high.

cow-micro

Jende Leather Strop, Micro

roo-micro

Jende Kangaroo Strop, Micro

The spotted surface of the cow leather reveals a smooth surface with raised polyp-shaped mounds. The kangaroo leather shows a smooth surface with divots where the hair follicles are. It is this difference that really influences the the way each strop works.

My theory is that he raised polyps on the cow leather will come into contact with the blade when stropping, making the strop more aggressive but arguably slightly less consistent. If you were to load the strop with an abrasive, the abrasive would leave deeper scratches at the polyps and more shallow scratches in between. Again, arguably more aggressive but less consistent.

The divots on the kangaroo leather do not interfere with the stropping action of the rest of the surface of the strop, meaning you get more consistent contact with the strop when stropping. When the kangaroo is loaded with an abrasive, the contact between the blade and the strop is much more constant as well since the abrasive fills in the gaps. The catch here is that this could be considered less aggressive since the surface scratches are not as deep, but because more edge is in contact with abrasive throughout each stroke, it could still be described as as aggressive since there is more shallow depth of scratch per stroke, but a whole lot more of it. It’s a different kind of aggression.

So what does all this rambling mean? Well, based upon the picture evidence, there is a strong argument to be made that the polyps of the cow leather make for a more aggressive stropping medium and the divots of the kangaroo make a smoother stropping medium. This is the simple answer, of course, and doesn’t factor in things like stropping technique and pressure. But is does remain a constant that the cow leather has raised polyps and the kangaroo has divots, and this is the information needed to begin making an informed decision as to which stropping medium is better suited for your needs.

To give an example, a 2K edge on a hunting knife can get more out of a cow leather strop since it will push the edge back into position with more force. That same cow strop loaded with a 4 micron (4K) Jende emulsion takes the knife edge up a notch while still being aggressive enough to maintain the edge between sharpening sessions. On a straight razor, a kangaroo strop will push the fragile edge back into a more uniform position. The same kangaroo strop loaded with 0.25 or 0.10 Jende emulsion will abrade the edge of the razor more evenly, thus minimizing microchipping while keeping the scratches very consistent. You can just imagine the possibilities from here!

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TOG Elite Japanese Kitchen Knives Review

April 25, 2016

We recently received a TOG Elite Japanese Kitchen Chef Knife Santoku for testing. Bottom Line: This is one very nice knife that handles well, keeps its edge, and just plain looks good.

TOG Elite Japanese Knives

TOG Elite Japanese Knives

 

On the TOG website, there is a “Tech Specs” page that lists all the wonderful, interesting, and even nerdy things about the knives.  I’ve decided that my review will focus around the claims on that page.

  • “TOG blades are made from a special steel… to produce the ridiculously sharp blade and ensure that it stays sharp.” 
  • “Incredible cutting performance from a central layer of high-carbon (1%) steel. This core is made from… Acuto 440 that is similar to Western ‘440C’. This is hardened to Rockwell Hardness (HRC) 58-60…”

As an OCD sharpener, any claims to sharpness are always met with (rolled eyes or yawn) “Oh, yes, it is.”  I then proceed to lick the entire edge of the blade  – twice.  🙂 The TOG blade, however, actually looked and felt surprisingly sharp upon checking the edge right out of the box – sharp enough for me to not employ the old tongue test. So I went straight to the paper cutting test, expecting a typical 240 grit with a buffed edge feel. I was shocked by my first cut, so much so that I took another slice into the paper just to make sure. This thing cut -no- SLICED through the paper in a way that was not the usual factory edge. This was much, much better. I was truly impressed. If I had to call the grit, I would say about 3K. Score 1 for TOG right out of the box.

Edge retention is always going to vary depending on the user and the tasks performed, but when I sharpened up the TOG to my usual angles and finish, it kept up as good as, if not a little better than my usual knives (RC57-58). The knives in the rotation were all freshly sharpened by me, and used in a professional kitchen over a 2 week period with no special treatment (believe me!), and were only adjusted with a sharpening steel by the sometimes brutish kitchen personnel.

Steel junkies say what you will about 440C, but the Acuto 440 steel in this blade is perfect at RC 58-60. IMO, RC 56-60 is the Goldilocks hardness zone for high quality, non-custom kitchen knives – hard enough to hold the edge so that it does not require steeling after every cut, and flexible enough so that the edge won’t chip out. RC 58-60 also makes maintenance on the edge easy and straight forward on just about any good quality sharpening equipment, be it a steel, stones or mechanized sharpeners. I used 220, 1K, and 4K sharpening stones and got a smooth edge with just enough bite. As a sharpener, I am quite satisfied with the quality.

As for the feel of the edge when in use, it actually felt more akin to VG-10 steel, and not even remotely close the soft mushy stuff that your 29-piece knife set in a woodblock has (usually RC ~52). The overall balance and handling of the knife was easy and light, and the thinness of the blade allowed for easy cutting and slicing.

So to sum it up, this is one very nice knife that handles well, keeps its edge, and just plain looks good.

Thank you to the fine people at TOG for the opportunity!

Microscope Porn: How To Post It Correctly

August 1, 2015

With all the microscope porn on many of the sharpening and honing social media and forums lately, there needs to be a more standardized way to document the magnification. There are many available microscopes on the market, and the stated magnification levels are all over the map – from 3x to 1200x. Ironically, having the magnifications in these settings is irrelevant because we can enlarge and magnify pictures for various viewing needs, which often contradicts the stated magnification. It is therefore more important to know and state the actual area or size of the picture.

This tutorial will help to solve some of the uncertainties about knowing what the actual size of your pictures are rather than the so-called magnification. Please keep in mind that this is not in any way a comment on the quality of any of the scopes mentioned here. They are all very good, and extremely useful learning tools.

So, the easiest way to know your picture’s dimensions at a given magnification is to simply take a picture of a ruler under your scope, and state the dimensions when posting pics. This could be a USB scope, a scope attached to your cell phone, an optical scope, etc..

Below is a Veho at  20x. The pictured area is 6mm wide by 8mm high.

1 Ruler 20x ~6mm high

Ruler 20x ~6mm high

5 Ruler 20x ~8mm wide

Ruler 20x ~8mm wide

However, the Veho at 40x is 10mm high by 13mm wide! According to the magnification, the image sizes should be smaller (in theory, 3mm high x 4mm wide), but clearly the USB scopes don’t magnify the same as the scientific ones do. Hence, the issues with stating magnifications vs. stating the actual size of the pictured area.

2 Ruler 40x ~10mm high

Ruler 40x ~10mm high

6 Ruler 40x ~13mm wide

Ruler 40x ~13mm wide

To take it a little further, here is the Veho at 200x, which is 1mm high by 1.5mm wide. This is hardly a 10 times or even 5 times magnification of the 20x or 40x above.

3 Ruler 200x ~1mm high

Ruler 200x ~1mm high

7 Ruler 200x ~1.5mm wide

Ruler 200x ~1.5mm wide

And lastly, the Veho at 400x, just to drive the point home. 🙂 the picture is 0.75mm high by 1mm wide. Again, not the same ratio of magnification to the real size of the picture.

4 Ruler 400x 0.75mm high

Ruler 400x 0.75mm high

8 Ruler 400x ~1mm wide

Ruler 400x ~1mm wide

OK, so we get that part now. 🙂 On scopes with software packages, you can measure out the dimensions, and even set a “bar,” which represents a specified length, much like a map has a scale in KM or miles. In the example below, famed razor honer Dr. Matt has set his Dino Lite scope’s bar to 50.0 microns, which can be seen in the lower left hand corner of the picture. That means the entire area of the picture, no matter how large or small on your screen, will be approximately 300 microns wide by 250 microns high, or 0.3 mm wide by 0.25 mm high. Dr. Matt’s microscope is quite nice, you’ll notice there is also more information on the top tabs of the picture, including the “magnification” and screen resolution in pixels.

Dr. Matt’s bar is 50 microns

While Dr. Matt’s image as-is is self explanatory, if he didn’t have the bar or tabs and was citing this picture for others, he would say something like “This picture was taken with a Dino Lite 900, and the picture dimensions are 0.3 mm wide by 0.25 mm high.” This way we all know for sure just how close we are to getting our eyes sliced opened. 😀 BTW – stating the actual size of this picture makes Matt’s work even more impressive!

In conclusion, taking just a little time and a couple of pictures before hand to measure the actual size of your pictures will prove to be a more valuable asset to understanding what these pictures represent, and therefore make learning from them easier for the user, and for the rest of us in the peanut gallery. Thanks!

Diamond Bars by Ken Schwartz – For Buffers

November 17, 2014

We’re happy to announce that we now have Diamond Bars from Ken Schwartz! These specially formulated diamond bars are packed full of diamond abrasive, making them very fast, and very consistent. They also come in a wide range of grits – from 80 micron down to 0.10 micron! So if you’re removing rust from a blade, repairing chips, profiling or reprofiling, sharpening, or polishing the blade, these bars are essential.

KME Sharpener Chosera Stone Introduction

April 6, 2014

Tom Blodgett of Jende Industries demonstrates the Chosera stones available for the KME Sharpener. In terms of guided sharpening systems, the KME is one of the best systems on the market. With the Chosera stones now available for it, it adds a whole new level of versatility. There is a nice surprise at the end, so please do enjoy the video in its entirety. 🙂

In this video, I prepared the initial edge on this knife with the stock KME diamond plates at 22 degrees per side, and then used the 1K, 3K, 5K, and 10K Chosera stones.

There are 8 Chosera grits in all:

400, 600 & 800 are best for initial profiling, repairs and make great transition stones from the stock KME diamond plates. These stones leave an aggressive, toothy edge. The 800 leaves a very good “working” edge.

1K, 2K, 3K are best suited for maintenance and light repair. These stones refine the edge that is on par, and often better than more traditional sharpening levels. The 1K is an excellent “working” edge, and the 2K and 3K leave an edge that easily slices, but still has a little “bite”.

5K & 10K stones are truly polishing stones – they take the sharp from the 1K, 2K, and 3K and polish/refine the edge even further – these are the game changing grits. The knife will slip effortlessly through things, and yes, you can shave your face directly off the 10K. It is a great platform from which to continue on to even higher finishes using the strops and compounds available for the KME.

You can find the KME Sharpener and Chosera stones on the KME website, and the Choseras for the KME are also available from Jende Industries, LLC.

 

Maestro Wu Bombshell Steel Knives in action – Video Heavy

February 9, 2014

A while back I did a series of videos to introduce the Maestro Wu Bombshell Steel Knives. They are grouped here into similar-functions – for example, the chef knives like the D-6 and D-7, the curved knives used in a rocking motion, such as the D-3, D-4 and D-9, the slicers like the D-8, D-10, and D-11, and the meat cleavers like the D-5 and D-12. There is a size and shape for every need. Please enjoy!

And just for fun…

Sharpening Philosophy Part 3 – Mechanized vs. Manual Sharpening

January 6, 2013

Establishing the beginnings of your own sharpening philosophy before making any purchases of equipment and supplies will not only help you save money in the long run, but will help you better find your desired path when embarking on your sharpening journey. This third installment looks deeper into Mechanized vs. Manual Sharpening.  Before reading this post, it is recommended that you read the  introductory sharpening philosophy article.

To recap, the main categories are as follows:

  1. Speed vs. Cost vs. Precision (-pick any 2)
  2. Mechanized vs. Manual Sharpening
  3. Guided vs. Freehand Sharpening
  4. Maintenance vs. Full Service Sharpening

Choosing between Mechanized and Manual is not always as easy as you would think. This is a pretty big topic with lots of options and arguments for and against both categories. And while the fight between the camps won’t be definitively solved here, making some decisions at this level will point  you on a more clear path as to which kinds of sharpening equipment and methods you should be considering.

A quick definition of mechanized sharpening is any sharpening equipment that uses a motor or moves independently of the user. Manual sharpening is done by hand, and uses “human” power. Just to be clear, guys using bicycles  or hand cranked sharpeners to sharpen would be considered mechanized since the wheel is turned through mechanical means and spins independently of the user. 🙂

One thing for sure is that mechanized is faster while manual sharpening is comparably slower, but mechanized sharpening can be more invasive than manual sharpening. There will be sharpening situations where one system’s advantage for sharpening one thing becomes a disadvantage when sharpening something else. So once again, it depends on what you are sharpening and what you want to achieve.

MECHANIZED SHARPENING

Mechanized sharpening is more of a no-nonsense, “Get ‘er done” approach to sharpening. It’s fast, as in high RPMs, and is best suited for larger sharpening loads (50+ per day/week), repair work, and for a no frills, quick turnaround time. It’s biggest detractor for sharpening is that faster  RPMs equals heat buildup on the blade, and the possibility of  bluing or burning the metal (which draws out the carbon and makes the blued area useless). This is easily controlled with a little bit of technique, some attention to the temperature as you sharpen, and a bucket of water/coolant nearby. Higher end machines will often have a variable speed option either built in or available as an add-on.

Within the mechanized sharpening camp, you have three basic types of machinery – belt systems, wheel systems, and disk systems. There are usually several accessory guides and jigs available for these systems, which add a level of precision to their speed (and increase the overall cost). Most of the mechanized sharpening products come in small, medium and commercial sizes, which is most often reflective of the horse power of the motor (1/4HP is small, while 3 or 5HP is commercial). The majority of these systems are run dry – without coolant or water directly on the belt, wheel or disk, but there are wet systems out there.

BELT SYSTEMS

Belt systems are pretty much belt sanders that use various length and width belts. The most common belt lengths and widths are 30″, 36″, 42″ and 72″ long and 1″ or 2″ wide. There are several main types of abrasives available, including Silicon Carbide, Aluminum Oxide, Zirconia (ceramic) and Diamond. There is a very wide range of lower grit belts available, with the most options being in the #60 to #320 grit range. There  are also belts that go much higher in grit – like 4 and 6 micron (#2,000 and #3,000 grit), and even finer – like 0.5 micron (#30,000 grit!). There is a large variety of belt “strengths” out there, too, which are formulated for lighter or heavier uses. Aside from abrasives belts, there are also leather and belts made from other materials that can be charged with compounds and sprays, giving them a huge grit range. You can go crazy as you want with choosing belt progressions, but most people stick to 2-3 belts because you can make large leaps in grit due to the speed of abrasion.

WHEEL SYSTEMS

Wheel systems are interesting – and they are more diverse than people think. Grinding wheels are generally some sort of vitrified abrasive in the #36 to #120 grit range. This is the most aggressive side of sharpening – you know, the one where sparks are flying like a mini launch of the space shuttle. There are more specialized abrasive sharpening wheels out there in the  100-3K range, and there are wheels which spin much slower or with variable speed options. Some wheeled systems will employ more than one wheel at a time.

Sandpaper flap wheels are another example of wheel systems. They are hundreds of sheets of sandpaper bound in a wheel of various diameters (generally from 4″ to 10″) that fan out and abrade the surface. Flap wheels are less aggressive than stone wheels, and are more akin to belts. The range is generally from #60 to #320 Grit.

There are also many wheel sharpening systems that can be charged with a wide variety of sprays and compounds, including wheels made from paper, plastic, cotton, canvas, and leather. All have different abrasion speeds and properties. Just a quick reminder that once a wheel is charged with a given grit or compound, it should remain that grit exclusively to avoid cross contamination.

DISK SYSTEMS

Sharpening Disks are circular and spin flat or horizontally, like records (or CDs if you’re too young!) Most of the disk sharpening systems I’ve seen are related to the hair shear/scissor sharpening world and can use 3-6 disks. The others I’ve seen are in all out  industrial settings, but there are a few smaller, singular disk options out there. The disks can be abrasive wheels, ranging from silicon carbide to aluminum oxide to CBN and diamond, or they can be replaceable sheets of abrasive films of varying grits.

MANUAL SHARPENING

The biggest attraction to Manual Sharpening (IMO) has to be all the different possible edge types that can be obtained from the variety of equipment that is available. Basically, every product produces a tangibly different edge, which allows for total personalization. That’s not the only draw, there’s also the Zen aspect where you can control every pass, the challenge of mastering the techniques, the overall lower costs and space requirements (depending on how deep you fall into the rabbit hole!),  not to mention the greater portability aspect. And while the speed of manual sharpening is somewhat slower than mechanized, you can still get some work done when you need to. 😉

Manual sharpening is broken into two highly opinionated and often confrontational camps – Freehand and Guided sharpening. These will be looked at in greater detail in another post, but for this level of Mechanized vs. Manual sharpening, guided sharpening employs guides and/or jigs that increase precision while freehand sharpening gives greater freedom to make on the fly adjustments. However, manual sharpening, be it freehand or guided, can generally be done on the same types of abrasive mediums.

Those mediums include sharpening stones, abrasive films and papers, and strops.

SHARPENING STONES

Sharpening stones is a huge topic. There are basically 2 types of stones, though – Natural and Synthetic – and with many different stones populating both groups. It’s this variety of stones that allows for complete personalization of an edge, and opens up several more subtopics in more advanced philosophical discussions. One the most appealing aspects of sharpening stones is not the wide range of grits and makers, but how the stone’s binder and/or composition effects the stone and the sharpening results – which is yet another subtopic!

For now, we will focus on the basics – Naturals are stones found in nature, and are mostly named for the places they are/were mined. There is no absolute grit rating for naturals since they are not completely uniform or consistent in their abrasive size or composition, so they are usually rated as coarse, medium or fine stones. The grit range is quite extensive, and is comparable to that of synthetics, with some arguing that some naturals can go even finer. The good news is that the specific names of the stones will almost always tell you which grit category they fall into.

There are no set dimensions to natural stones, but most of them are 1-3″ wide by 2-8″ long with varying thicknesses. Depending on the kind of stone, it may have chipped off corners, and/or tapered sides (the weak parts of the stone are chipped off to ensure its integrity). Natural stones are generally “harder” which means they do not dish so readily, and they use either water or oil as a lubricant, depending on the type of stone.

Synthetic stones are man made from various abrasives, usually silicone carbide and aluminum oxide. There are also diamond impregnated plates. The abrasive grit sizes are much more controlled, and the stones are referred to by their manufacturer’s name and the corresponding grit (there are several grit standards used, though). The range of grits is generally from #120 (#120 micron) to #30,000 (0.5) micron. Most full size stones are around 3″x8″ with varying thicknesses – anywhere from 5mm to 3 inches. There is a wide range of hardness amongst synthetic stones – some dish more readily than others while some polish more than others.

Amongst synthetics, there are oil stones and water stones. As their names imply, oil stones use oil as a lubricant while water stones use water. You can use water on oil stones (but not after you already used oil), but you shouldn’t use oil on water stones – ever.

ABRASIVE FILMS AND PAPERS

Abrasive films and papers are your basic sandpapers, which use a variety of abrasives, including the more traditional emery and feldspar, and they have grown to include longer lasting abrasives such as silicone carbide, aluminum oxide, CBN and diamond on more robust film backing. Films and papers are generally cheaper than stones, but the tradeoff is their lifespan, which is more limited compared to sharpening stones since the abrasives are not renewable. However, with their flexibility and the fact that they are paper or film, they can be cut to a specific shape and/or size and transported easily. Abrasive films and papers can be used either wet or dry, and used with a variety of backings for different results –  such as mouse pads, leather, glass, or granite.

STROPS

The use of strops has increased dramatically lately, and that probably has something to do with the increase in stropping mediums now available. Traditionally, the leather strop on its own has been used to tweak an edge, or to get it back into working position. But strops can also be loaded with abrasive sprays and compounds, making them act more like renewable abrasive papers and films. As with sharpening wheels, once a strop is charged with a given grit or compound, it should remain that grit exclusively to avoid cross contamination.

The most traditional stropping material is cow’s leather, but that has expanded to include horse, and even kangaroo leathers. A canvas strop has always been the compliment to a barber’s leather strop, and they can be made from a variety of textiles such as cotton, flax, hemp, felt, denim, nanocloth, vegetable leather, and even newspaper and other types of specialty papers, such as rhodia paper. These too can be loaded with abrasive sprays and compounds.

Balsa wood has become a popular “hard” strop, but you can add a soft or hard backing to any of the stropping materials above.

CONCLUSION

Choosing exclusively between mechanized and manual sharpening is a big decision, and it’s not always an easy one since there are many versatile options in each category. It really boils down to how much and what kind of sharpening you plan to do, how fast you want it done, and how personalized you want the results.

If you are serious about sharpening – and especially if you plan on sharpening other people’s knives or tools – you will want to have some sort of mechanized sharpener for major work such as tip repairs, large chips, and serious reprofiling  – even if you end with manual sharpening methods to put your personalized finished edge. If you simply want to maintain a few knives or tools, manual sharpening is more economical, and with a little extra time, the coarser grit options for manual sharpening can usually take care of all but the most serious damage.

Finding Your Sharpening Philosophy

November 3, 2012

There is a HUGE range and variety of sharpening products and methods out there, and before going any further down the sharpening rabbit hole, forming  a sharpening philosophy can help you save time and money in the long run.

When you first embark on your sharpening journey and start sifting through the usual pile of information that search engines, Youtube videos, forums, and blogs (like this one! ) spew out, it can be very overwhelming. In reality, there are only two constants when sharpening: the first is that the answer to every question is It depends; and the second is that The more you know about sharpening, the more you need to know.

The next logical question is What do I need to know? Well, the answer is, of course It depends! I’m glad we got that cleared up. 😀

Seriously, though, it’s not about answering “how to sharpen” (which is the easy part since the actual rules of sharpening are quite concrete) – it’s about asking and answering What do I want to achieve when I sharpen, and how do I go about it? The answers to these 2 questions are what form the backbones of your sharpening philosophy, and will guide you toward making purchases that are best for you.

The first major categories to think about are these:

  1. Speed vs. Cost vs. Precision
  2. Mechanized vs. Manual Sharpening
  3. Guided vs. Freehand Sharpening
  4. Maintenance vs. Full Service Sharpening

There are more categories to choose from as you progress deeper down certain paths, but these are the most important factors in the beginning.

  • Speed vs. Cost vs. Precision

The saying goes “Good, fast and cheap – Pick any 2”. Speed generally costs more, as do more precise results. However, if you are on a budget, less expensive products will still generally work. This is the is one major category that every decision will always boil down to. There is no “wrong” answer – it is completely subjective, and the answer can change at any time given the circumstances surrounding the decision(s).

Take a more in-depth look at cost vs. speed vs. precision here.

The second category will more clearly define the path of your sharpening journey:

  • Mechanized vs. Manual Sharpening

There is a definite split in the sharpening world between Mechanized and Manual sharpening. Both have many options to choose from, and both have their  pros and cons depending on the type of sharpening you are doing, and sharpeners can find a comfortable balance between them. Generally speaking, mechanized is anything with a motor – a belt sander, stone or paper wheel, grinders, etc., and are easily the fastest methods and are more aggressive than non-mechanized approaches.

Manual Sharpening is further broken down into Freehand and Guided sharpening, which are similar in terms of the types of sharpening mediums they use. They include sharpening stones, various abrasive papers, sprays, compounds, and stropping mediums, etc.. (More on this in a minute.) But overall, Manual Sharpening’s speed is slower, but results are generally more personalized and the process is more Zen-like.

So once you’ve decided where you stand in terms of Mechanized vs. Manual Sharpening, you will need to go one step further:

  • Freehand vs. Guided

With Freehand vs. Guided Sharpening, there is the obvious increase in precision with guides that makes them very powerful and almost idiot proof sharpening tools, however, the speed, skill and freedom of freehand sharpening has a large appeal as well. Note that both Mechanized and Manual sharpening can done freehand, or guided with various jigs and guides.

The final category to consider is:

  • Maintenance vs. Full Service Sharpening

In this case, Maintenance Sharpening is for someone who has several knives that are kept consistently sharp, and would like to simply touch them up here and there, with no real damage to repair or major sharpening to be done. Full Service Sharpening is being able to perform all aspects of sharpening from making repairs to chipped edges, profiling new blades, and maintaining edges over time.

This is not a black and white category – there is an overlap of abilities with many of the products and methods. Most Maintenance-minded sharpening products and methods will perform repair tasks, and Full Service-minded sharpening products and methods are perfectly suitable for maintaining edges.

Conclusion

If you’ve taken these 4 categories into consideration, you should start to have a better view of what kind of sharpening you want to do, and which products and methods you may want to consider given the specific things you want to sharpen.

Your philosophy is not set in stone – it will change and develop as you continue on your journey  – don’t forget – the more you know about sharpening, the more you need to know. For example, there are more advanced categories to consider, such as sharpening for Aesthetics vs. Functionality, “True grit” edges vs. Polished Grooves – just to name 2.

Remember – It Depends!

Diamond Sharpening Films by Ken Schwartz – in 1×6, 2×6 and 3×8

September 14, 2012

With the ever increasing development of the super abrasion-resistant exotic Uber-Steels in the knife world, conventional sharpening stones are being pushed to their limits, and Ken Schwartz has come to the rescue with his Diamond Sharpening Films.

Almost everyone has a DMT and/or an Atoma diamond plate, but these are super aggressive plates that are great for heavy duty repair and profiling work. For the most part, they tap out at #1,200, or 7 micron, and even although DMT has a 3 micron plate, it isn’t nearly as popular as the lower grits. Traditionally, if you wanted more refinement, switching over to diamond pastes was the answer, but as we’ve been finding, pastes generally don’t have nearly as much “punch” as the plates. This is due to the overall lack of abrasive concentration, and the fact that while the size of the abrasives are consistent, the depth of scratches from the plates are much deeper than those from the pastes.

So the problem lies in finding an all-diamond progression, on a consistent medium, AND with a huge range of grits. Ken Schwartz has found that solution with his diamond films on Float Glass, which range from a whopping 165 micron (100 grit) to 0.1 micron (150,000 grit!). Not only that, it’s currently available in several sizes: 1″ x 6″ for the Edge Pro, 2″ x 6″, and a “full size” 3″ x 8″. They can be custom ordered to size as well. 😀

I have a couple of Uber-steel knives, including a Rex-121 Mule from Farid, but we all know diamonds can sharpen anything, including ceramic knives, so I opted for what would make the best microscope pictures – a straight razor. In this case it’s a vintage Torrey Wedge.  Besides, you don’t need super hard steel in order to opt for diamond sharpening. 🙂  The pictures were all taken with a Veho-400x USB scope and actual size of the pictures is .75 mm tall by 1 mm wide.

Since the Torrey was already in good shaving condition, I did not need to step back to the 165 micron diamond sharpening film, and opted instead to begin with the 45 micron (320 grit) to re-establish the bevel. I used the 1″ x 6″ Edge Pro size since it makes dealing with warps and other razor-related issues. In fact, I pretty much exclusively use the 1×6 size for honing razors.

1 Torrey 45 Micron Diamond

Torrey 45 Micron Diamond

From the 45 micron film, we can see an edge comparable to the #320 Shapton Pro – a little serrated, but quite consistent.

From here, I progressed to the 30 micron (500 grit) film.

2 Torrey 30 Micron Diamond

2 Torrey 30 Micron Diamond

30 micron (500 grit) is still quite coarse in terms of razors, but the edge of the edge is already starting to clean up.

Next is the 20 micron (800 grit) film.

3 Torrey 20 Micron Diamond

3 Torrey 20 Micron Diamond

Again, 20 micron (800 grit) is still quite coarse (and for razors is probably the coarsest grit needed, if at all), but things are looking quite nice. This would be acceptable for a working edge on a knife.

Then onto the 9 micron (1,500 grit) film.

5 Torrey 9 Micron Diamond

5 Torrey 9 Micron Diamond

I’m completely impressed with the 9 micron film. The edge is looking clean, and the scratches are much more consistent with water stones than diamond plates.

6 micron (3K grit)  is next.

6 Torrey 6 Micron Diamond

6 Torrey 6 Micron Diamond

As we can see from the difference in the reflective lighting on the bevel, we have entered into the “critical leap” area of the films. There is definite polishing happening at this stage, so we can say the critical leap is between the 9 micron and 6 micron. However, I personally feel it’s between the 6 micron and 3 micron (6K), as we will see below.

7 Torrey 3 Micron Diamond

7 Torrey 3 Micron Diamond

The reason I would rather call the 6 to 3 micron the critical leap is because of the sheer “flatness” of the bevel off the 3 micron. Either way, at this point we are certainly sharp, and headed toward the land of shaving!

The 1 micron (15K) film is next.

8 Torrey 1 Micron Diamond

8 Torrey 1 Micron Diamond

Although the edge of the edge is certainly consistent and able to shave,  we begin to run into some razor-related issues. This picture is reminiscent of the 16K Shapton Glass post I did a while back, where the Swedish steel was quite brittle, and began to chip out as the steel got thinned beyond it’s capability. That has much more to do with the characteristics of the steel, and NOT the quality of the diamond films.

9 Torrey half Micron Diamond

9 Torrey half Micron Diamond

Here we can see the 0.5 micron (30K grit) film is pushing the limits of the Torrey, however,  the bevel itself is quite clean.

Since I was also testing a progression of Ken Schwartz’s diamond sharpening films for a razor customer, I switched here to finish the razor on Ken Schwartz’s 0.125 micron CBN on balsa instead of going to the 0.1 diamond film, as was requested.

Conclusion

Obviously, the diamond films work, and they deliver in full from coarse to ultra fine grits. You also don’t need super hard steels in order to use or benefit from the diamond films, and since we are dealing with diamond abrasives, you get much longer cutting action out of them than conventional sand paper. Ken Schwartz has hit a home run in my book!

By the way, the shave was wonderful 🙂

DMT vs. Atoma Diamond Plates For the Edge Pro – A Microscopic Comparison

September 25, 2011

Since we added the Atoma diamond plates for the Edge Pro to our website, people have been asking what the differences are between them and the DMT diamond plates.  I thought that these microscope pictures of each series may help you choose which is best for your needs.

I will say that the only major difference is that the Atoma is available in a standard EP size –  1″x6″ while the DMT is only available in the 2″x6″ size.  The standard 1″x6″ obviously makes things more consistent, but there are advantages to the 2″x6″ as well, especially with longer knives.

It is also quite obvious that the DMT diamonds are “sprinkled” into the matrix while the Atoma diamonds are precisely placed “clusters”. As with everything sharpening, arguments can be made for and against the merits of each, depending on specific situations. I will make my personal comments at the end of this post.

So on to the pictures 🙂

All photographs were taken with a Veho 400 USB microscope at 20x for macro and 400x for micro, and are approximately 13mm wide x 10mm high and 1mm x 1mm, respectively. The pictures have been re sized to fit the format on this blog, but no other alterations were made. Here are the links to the original photos for the Atoma and the DMT plates. All of the plates pictured are already broken in. Atoma does not have any official micron ratings as of this post, so all sizes are loosely compared to the JIS (Japanese) standard.

First up are the Atoma #140 and DMT Extra Coarse. These are not equivalent comparisons, as the the Extra Coarse is 60 microns or #220 grit, and the #140 Atoma is more closely related to the Extra-Extra Coarse (XXC) DMT, which is rated at 120 microns.  You can easily see the major size difference. Nonetheless, these two are the coarsest of the bunch available for the Edge Pro.

#140 Atoma Diamond Plate

#140 Atoma Diamond Plate – Macro

DMT Extra Coarse - Macro

Extra Coarse DMT Diamond Plate – Macro

#140 Atoma Diamond Plate - Micro

#140 Atoma Diamond Plate – Micro

Extra Coarse DMT Diamond Plate - Micro

Extra Coarse DMT Diamond Plate – Micro

The Extra Coarse diamonds at the micro level almost look like pebbles on a beach in comparison to the giant, almost 1mm wide cluster of diamonds in the Atoma (don’t forget – the Atoma is rated much coarser than the Extra Coarse DMT).

Next are the Atoma 400 and the DMT Coarse. These two plates are more closely matched in terms of micron sizes with the DMT Coarse being 45 microns (#320 grit), and the #400 Atoma falling into the JIS 400 range, which is 40 microns.

#400 Atoma Diamond Plate - Macro

#400 Atoma Diamond Plate – Macro

Coarse DMT Diamond Plate - Macro

Coarse DMT Diamond Plate – Macro

#400 Atoma Diamond Plate - Micro

#400 Atoma Diamond Plate – Micro

Coarse DMT Diamond Plate - Micro

Coarse DMT Diamond Plate – Micro

The DMT coarse clearly has a more even coating than the Extra Coarse DMT, and the Atoma #400 cluster is roughly half the size and height of the #140.

Onto the Atoma #600 and DMT Fine. The DMT Fine is 25 microns while the JIS 600 puts the Atoma #600 at around 29 microns.

#600 Atoma Diamond Plate - Macro

#600 Atoma Diamond Plate – Macro

Fine DMT Diamond Plate - Macro

Fine DMT Diamond Plate – Macro

#600 Atoma Diamond Plate - Micro

#600 Atoma Diamond Plate – Micro

Fine DMT Diamond Plate - Micro

Fine DMT Diamond Plate – Micro

At this level, the Atoma #600 ‘s cluster seems to have reached it’s smallest width, and the DMT Fine has a dense, even coating of diamonds.

Lastly, is the Atoma #1200 and the DMT Extra Fine. The DMT is rated at 9 microns, while the JIS standard loosely puts the #1200 Atoma at 13 microns.

#1200 Atoma Diamond Plate - Macro

#1200 Atoma Diamond Plate – Macro

Extra Fine DMT Diamond Plate - Macro

Extra Fine DMT Diamond Plate – Macro

#1200 Atoma Diamond Plate - Micro

#1200 Atoma Diamond Plate – Micro

Extra Fine DMT Diamond Plate - Micro

Extra Fine DMT Diamond Plate – Micro

Personal Thoughts

As with all things sharpening, the answer to which is better is “it depends”. There is no doubt with my experiences that the DMT and Atoma diamond plates both deliver, they just do it differently.

The Atoma plates have a lot of positive things going for them: the #140 is certainly more aggressive than the Extra Coarse DMT, making it a better low end plate for profiling and chip removal. The systematic grid pattern of the Atoma plates make the diamonds less likely to “rip out” – for example, the knife may get between the spaces between diamonds on the DMT Extra Coarse. The Atoma plates also leave a very predictable scratch pattern at each level, which really appeals to my OCD and completely compliments the way my Shapton stones work. The clusters seem to ensure a longer lasting life of the plate, too.

But the Atoma plates come at a cost – literally. The labor in making the Atoma, while worth the cost IMO, may be a little over budget when compared to the price of the DMT plates.

Aside from the price factor, the DMT plates also have a larger surface area, which makes them better suited for working on longer knives, and even arguably faster since there are 2 inches worth of abrasives vs. 1 inch on the Atoma plates.  The sheer density of the diamond coating on the Fine and Extra Fine DMT plates leave a very even finish and “smooth” scratch pattern, as well, which makes progressing to the next stone level easy.

So once again, I recommend getting them all and trying them for yourself 🙂 One thing is for certain in all this – I don’t see either series getting much rest between performances 🙂