Thought on Hand Stropping with cheap compounds?

[Ken Schwartz]

Well a few comments here on this post and some subsequent posts.

Regarding the medium or substrate that the compound is on:

I feel that leather does have it’s place as well as harder substrates. Of course the pressure applied makes a hugh difference here. Convexing an edge is both a measure of the substrate’s ‘give’ as well as angular consistency. So you have a range of substrates going from softest to hardest for example:

Thick neoprene / mouse pads

Thinner neoprene – various thicknesses found at dive shops – thinner has less give generally
Cardboard from corrugated to thin cardboard to card stock or index cards. This continues to various papers which can themselves be supported by various media (the substrate’s substrate).

Leather. Not all leather is the same – at all. So soft thick cowhide has much more give than thin Kangaroo hide. Here the surface characteristics also come into play. The edges I get from Kangaroo that is about the thickness of index cards allows for less convexing OR more pressure or somewhere inbetween – ie technique differences.

Woods. Various woods have different amount of give. Depending on the compound and grit sizes some are more ideal than others. I find that a slightly softer wood like Balsa is ideal for many things because the slight bit of give lets the particles stay in place a bit better. Too hard and the particles roll around. Harder woods like Baltic Birch do give a good flat surface, but particles slide around a bit too easily for my tastes. This is similar logic to using a soft steel platen to help the particles stick rather than just roll off on a harder steel surface. Of course different woods will have different abrasive properties themselves.

Paper. Revisiting this separately, paper can give one of the harder surfaces over glass, similar to films. Paper qualities become more critical at the finer grits as one competes with the clay abrasives that are a common contaminant of the paper manufacturing process, to say nothing of the abrasive qualities of the wood pulp in paper. Cotton and sugar cane pulps can give a finer finish in many instances, with cotton typically thicker stock and bagasse or cane pulp yielding very thin paper. My preference for paper with finer compounds is Rhodia or Clairfontaine. For coarser grits, just plain copy paper suffices.

Nanocloth – here you have the extreme of a neutral substrate, giving an absolute minimum of abrasiveness, allowing a pure effect from the compound applied.

Now angle control also produces convexity. So if you can control this, then the ‘give’ of the substrate is more worth consideration – like the control a WE affords.

Compounds can be put directly on film or be stuck to them as part of the manufacturing process. Like sharpening belts, there are various film substrates with specific qualities.

Waterstones – You can use various compounds on the surface of stones. This, depending on the stone gives a fairly hard surface to work with easily flattened to maintain precise flatness.

We have a similar issue with grits. Finer grits are best appreciated when other variables are controlled.

While we don’t have or need the luxury of a level five clean room, a few things will give us adequate control. KEEP strops with finer compounds in their own ziploc baggies. An uncontaminated ziploc gives you all the control of contaminants you need in a practical sense. When you aren’t using them, keep them there to reduce airborne contaminants.

There is no need whatsoever to associate what you can see in terms of finish with that being your rate limiting level of finish. You will get a mirror finish with a 5k Shapton, but certainly you can go past that in terms of sharpness. Indeed many cheap compounds do. But the biggest problem with cheap compounds is their inconsistency. You see this in particle size distribution data. You also have an issue of particle hardness with some particles eg iron oxide vs diamond or CBN. To say that a cheap supposedly 0.5 micron chromium oxide particle doesn’t require a clean room but a 0.25 particle does just doesn’t make a lot of sense.

And then there are natural stones. Here you have a hardness level that has a complex distribution and a particle size distribution equally complex with particle sizes varying during use as the mud refines, producing a more complex edge which has less of a single point of failure.

Here too you can separate the abrasive from the substrate by applying the mud produced from the stone to various substrates. Want a hakka stone that has little give? – put the mud on a hard surface (paper over glass). Want a soft version of say a Nakayama Asagi? – put it on a soft substrate like paper over neoprene. I often use balsa for these preparations. And of course you can blend natural stone slurries with CBN and diamond too for some superb effects.

Personally, I don’t think the price of a compound should be the chief concern. If a single spray of a concentrated compound of known formulation is used, the cost per sharpening is miniscule since a bottle will last SOOO long. What is more important is the value of your labor. I’m not saying this to be offensive, but having explored the realm of ultra refined small particle compounds, there truly is a difference in results best appreciated by trying it, as Clay mentions in his posting. There is sharp, there is sharper and there is even sharper. I thought I knew what sharp was, but I have proven myself wrong so many times that now I just look forward to reaching the next level.

—
Ken

Like any kind of stropping, aside from touching up the edge, it is also slowly convexing the edge. So eventually that bevel will change its shape to the convex shape we know and love. Nothing wrong with that! But if you want, it is but a few minutes work on the WEPS to get a nice sharp shoulder with the attendant bevel. Sweet!

Leo

Well you could use the strop mounted on the paddle to freehand sharpen as well, but as LEO points out, stropping on the WEPS will give you greater precision and less rounding of the edge over time. Precision stropping is especially advantageous if you are using several levels of refinement (grits) stropping as opposed to just your final strop. Of course, the compounds you use for stropping on the WEPS can be applied to bench sized strops as well. And the cheap compounds could be used on the WEPS too (not that I would recommend that, but I’m biased 🙂 )

—
Ken[/quote]

I did not realize that this thread was here on the forum, as I am a newbie to posting, and have limited understanding of how all this works. So long story short mistakenly I posted my thoughts about the above topics at:
http://www.wickededgeusa.com/index.php?option=com_kunena&func=view&catid=6&id=2304&limit=6&limitstart=6&Itemid=63 but will expand them here a bit..

Mentioned in my other post was my preference for non-leather strops and the use of cheap easy to obtain spanish cedar wood strips for a non compliant base material to hold strop compounds. I feel there is a strong case to be made for the abandonment of leather as the stropping material of choice. Now that you have a nice edge on your steel via the WEPS system, why should you convex it with a leather strop? It is the form compliant nature of leather that is causing the convexing, not the compound. I have been stropping blades for many years, experimented with all sorts of compounds and strops, and can say that (for me anyway..) the evil-doer of a bad strop is ( in order of issue..) : 1.) a compliant base material 2.) bad hand technique 3.) and running a distant third (if at all) is the compound itself.

For what is worth, I feel that in the world of knife sharpening, once you get past the level of any compound that is capable of mirroring the metal to the naked eye then you at the limit of what you can reasonably achieve for the purpose of knife sharpening. Discussions of 0.25 micron high purity CBN sprays and the like, are to me (sorry not trying to offend anyone) are more or less of an exercise in nonsense and probably frustration. It takes very specialized, and very expensive equipment to apply such abrasives in a productive way. If you are a technician in a Class 5 clean room, with the right equipment, and the task at hand is flattening the base for a space satellite sensor then yes maybe we should be talking sub micron abrasives.

So I say, go ahead and use “cheap compounds” … experiment, and have fun![/quote]

[Ken Schwartz]

I do think it is important to understand Verhoeven’s use of razor blades for his studies. It was not chosen to be a gold standard of sharpness, but rather a matter of practical convenience.

A razor blade will fit into the chamber of a SEM (scanning electron microscope). Most knives will not. Further, the SEM chamber requires a very high vacuum. in the range of 10 to the minus 6 torr (pardon the sloppy notation). For this the gasses in the handle will ‘outgas’ and contaminate the vacuum. This is the reasoning.

Obviously these razors have extremely thin geometry and the edges are at a more acute angle than even straight razors. They typically have a much coarser finish than many of the knives we sharpen off the shelf. This is also true with most scalpels. Sharpness is more a phenomen of geometry here than finish. Go to a grocery store and using a loupe, look over any number of razor blades and you will see coarse grind marks, not refined edges.

With knives and straight razors you will see notable improvements with edge refinement. But the TYPE of edge you use is task specific. Indeed for some tasks a certain amount of ‘teeth’ is desirable, moreso for tearing type motions. Thus you can cut a tomato skin by ‘ripping’ it with teeth, eg seratted edges, or actual teeth a la the never get dull type edges. But you can also push cut a tomato in thin slices with a very refined edge, eg a tenth micron edge. Here again it is important to distinguish edge geometry from finish. You can put a shaving sharp edge on an axe for instance, but it will require a more refined edge than what would be needed on a razor.

I’m certainly not condemning experimentation regarding compounds or sharpening in general. But having tried many myself, I’ve come to prefer a more precise preparation and more precise angle control. I’ve gone to landscaping yards to try stones, used India stones, various auto polishes, green sticks, all my wife’s buffing compounds she uses for jewelry, etc etc and tossed out many tests. If I had nothing else to use, I would use them. But I prefer better alternatives.

—
Ken

[BassLake Dan]

…. Go to a grocery store and using a loupe, look over any number of razor blades and you will see coarse grind marks, not refined edges.

—
Ken

Oh jeessh! .. as if I don’t already have enough problems with my local LEOs and my ex-wife attorneys ! :cheer: :cheer:

But seriously I will be responding to your detailed post with detailed comments of my own. Give me a bit of time for that.. and also I have to figure out the PM features here on this forum, as one set of my response is for you, and an edited version of that for public consumption.. :dry:

[Leo James Mitchell]

Curiouser and curiouser! said Alice. :ohmy:

Leo

[Ken Schwartz]

I believe I’ve mentioned this elsewhere, but for convenience, you might find these three articles I wrote useful in appreciating the difference in a well designed abrasive preparation vs some less well designed preparations – not necessarily cheaper, but more overpriced for what you are getting.

http://precisesharpening.blogspot.com/2010_12_01_archive.html

http://precisesharpening.blogspot.com/2011/01/part-2a-comparison-of-three-quarter.html

http://precisesharpening.blogspot.com/2011/01/cbn-cubic-boron-nitride-scanning.html

To repeat a quote from one of the articles:

“Quality is remembered long after the price is forgotten.”

—
Ken

[BassLake Dan]

I believe I’ve mentioned this elsewhere, but for convenience, you might find these three articles I wrote useful in appreciating the difference in a well designed abrasive preparation vs some less well designed preparations – not necessarily cheaper, but more overpriced for what you are getting.

http://precisesharpening.blogspot.com/2010_12_01_archive.html

http://precisesharpening.blogspot.com/2011/01/part-2a-comparison-of-three-quarter.html

http://precisesharpening.blogspot.com/2011/01/cbn-cubic-boron-nitride-scanning.html

To repeat a quote from one of the articles:

“Quality is remembered long after the price is forgotten.”

—
Ken

Ken,

Thanks for the above information and links, and no I guess I missed them if you had posted them elsewhere. Do I undersand where to obtain your products? Is that the product that Clay is sell here? Or do you have a separate ecommerce site somewhere?

You might remember me from my previous postings: I am the “cheaper is better guy”. I came up with a mod for the WE arms that cost 5 bucks, I use red iron oxide strop compound that is used on my jewelry bench (another hobby of mine!) that costs even less ! You get the idea :cheer:

Well I am preparing another post for later today where I respond to the last 4 or five posts from others. Certain statement that some have made here have caught my eye, and I want to quote them and then respond with my humble thoughts.

One thing has happened here as a result of all this discussion that has thrown me into action: I feel that my position is not defensible if i have not put it to the test. I had a sample of a 2 micron Diamond compound from some years ago sitting on my bench. It was part of a polishing kit I obtained for working platinum jewelry. I never used it for that purpose, but did try it on a few knives. I recall that I saw very little difference in those knives after the red iron oxide polish, so hence never felt motivated to by more samples or other even finer grits. i just let the whole subject fade away. But now we are all here disussing this issue. We have all sorts of issues, points of view, various vendors of product, SEMs of blades and compounds. WHEW! it’s enough to make my old head spin!

In the face of all that information I am nagged by the thought, “What if I am wrong and they are right?” After all, I never really tried any compounds that purport to being sub micron. So not to be on here just blowing a lot of hot air, and being an inveterate fiddler I decided to go ahead and obtain some samples and give it a go. We will see where that yellow brick road ends. One thing for sure –>>> it ain’t cheap! I have been busy on the internet and have on order sets of blank handles, leather handles, various grits in a range from Clays 3.5 down to 2 to 1 to .5 (two samples that: one Chromium Oxide, One Diamond) to a no name brand .25 and now your nice looking .25 to compare it to.. so it has turned into a $$$ project, probably 300 so far and counting! Guess now a need a good 400x stereo microscope,.. Hummm, well there goes my “cheaper is better”

Will post later with some comments in response to others POV… It will take weeks to actually test my new toys, and of course I have to wait for Elk season to see if Clay is right about all this :cheer: 😉 -Dan

[Ken Schwartz]

The compounds that I sell through Clay are the 0.125 micron CBN and the 0.050 and 0.025 micron polycrystaline diamond. Note the decimal points here – 0.025 is ten times finer than quarter micron. For other coarser compounds, just contact me via PM. My wife shares your hobby of jewelry making and I act as her tech support 🙂

Extrapolating your point of view based on a 2 micron diamond sample that didn’t work out well – Well what can I say? Two microns is roughly equivalent to a 8,000 grit Japanese waterstone particle in size and this is commonly used for sharpening, so I strongly suspect that it was a ‘cheap’ quality product of unknown or low concentration, poorly formulated and at a low concentration. We need to give you a better perspective on ‘the good stuff’. Waterstones go up to half micron particles, e.g., the Shapton 30k stones and produce a spectacular edge – without benefit of a clean room 🙂 Natural stones sometimes even exceed this level of fineness and have been used for hundreds of years. I do have for instance 2 micron polycrystalline diamond and CBN products if you wanted to compare it to your earlier results too.

I’m quite confident, based on my own extensive experience and those of my customers that you are on the verge of an epiphany in your sharpening journey.

You might find this thread useful additional reading:

http://badgerandblade.com/vb/showthread.php/181913-Did-I-just-shave-with-the-world-s-sharpest-straight-%280-125-Cubic-Boron-Nitride%29

The use of these fine compounds extends to both use on precision devices such as the WE as well as freehand and belt grinder applications. Compounds as fine as 0.5 microns have been used for years in these applications for refining knife edges. Indeed I can refer to Japanese literature dating back 50 years where this is recommended for final stropping on razors. This is true for both flat and convex grinds.

Let me know if I can help you in your studies.

—
Ken

I believe I’ve mentioned this elsewhere, but for convenience, you might find these three articles I wrote useful in appreciating the difference in a well designed abrasive preparation vs some less well designed preparations – not necessarily cheaper, but more overpriced for what you are getting.

http://precisesharpening.blogspot.com/2010_12_01_archive.html

http://precisesharpening.blogspot.com/2011/01/part-2a-comparison-of-three-quarter.html

http://precisesharpening.blogspot.com/2011/01/cbn-cubic-boron-nitride-scanning.html

To repeat a quote from one of the articles:

“Quality is remembered long after the price is forgotten.”

—
Ken

Ken,

Thanks for the above information and links, and no I guess I missed them if you had posted them elsewhere. Do I undersand where to obtain your products? Is that the product that Clay is sell here? Or do you have a separate ecommerce site somewhere?

You might remember me from my previous postings: I am the “cheaper is better guy”. I came up with a mod for the WE arms that cost 5 bucks, I use red iron oxide strop compound that is used on my jewelry bench (another hobby of mine!) that costs even less ! You get the idea :cheer:

Well I am preparing another post for later today where I respond to the last 4 or five posts from others. Certain statement that some have made here have caught my eye, and I want to quote them and then respond with my humble thoughts.

One thing has happened here as a result of all this discussion that has thrown me into action: I feel that my position is not defensible if i have not put it to the test. I had a sample of a 2 micron Diamond compound from some years ago sitting on my bench. It was part of a polishing kit I obtained for working platinum jewelry. I never used it for that purpose, but did try it on a few knives. I recall that I saw very little difference in those knives after the red iron oxide polish, so hence never felt motivated to by more samples or other even finer grits. i just let the whole subject fade away. But now we are all here disussing this issue. We have all sorts of issues, points of view, various vendors of product, SEMs of blades and compounds. WHEW! it’s enough to make my old head spin!

In the face of all that information I am nagged by the thought, “What if I am wrong and they are right?” After all, I never really tried any compounds that purport to being sub micron. So not to be on here just blowing a lot of hot air, and being an inveterate fiddler I decided to go ahead and obtain some samples and give it a go. We will see where that yellow brick road ends. One thing for sure –>>> it ain’t cheap! I have been busy on the internet and have on order sets of blank handles, leather handles, various grits in a range from Clays 3.5 down to 2 to 1 to .5 (two samples that: one Chromium Oxide, One Diamond) to a no name brand .25 and now your nice looking .25 to compare it to.. so it has turned into a $$$ project, probably 300 so far and counting! Guess now a need a good 400x stereo microscope,.. Hummm, well there goes my “cheaper is better”

Will post later with some comments in response to others POV… It will take weeks to actually test my new toys, and of course I have to wait for Elk season to see if Clay is right about all this :cheer: 😉 -Dan[/quote]

[BassLake Dan]

Ken,, thanks very much for the information, it is happily received here on this end ! I will check out the links you mention. Yes, I will continue on my sharpening journey, nothing stopping me now but my banker ! -Dan

[BassLake Dan]

Quote from Ken “… I thought I knew what sharp was, but I have proven myself wrong so many times that now I just look forward to reaching the next level.”

Ken, Your statement above caught my eye.. how have you established that one blade is sharper than another? has anyone been able to get there hands on and loan us one of these ? Actually have one on order myself, it is due to be delivered just after I win the next Mega-Lotto

http://www.catra.org/pages/products/kniveslevel1/surgredst.htm B)

[Ken Schwartz]

This is a difficult topic as no one has found a definition of sharpness that covers all cases and that satisfies all their needs for evaluation. In short, it is a tower of Babel.

Take the CATRA testing. It is essentially evaluating push cutting performance under strict guidelines. It is setup to detect the instant that a cut starts. Essentially a burst injury type of separation. It tells you very little of slice cutting performance. It also tells you little of how a blade’s overall geometry contributes or inhibits the ability of a knife to pass through an object or objects of different density. So, for instance, if you cut a cucumber slowly it may not cleanly separate, but with a bit more speed the inertia will ‘follow through’ and you get better separation. This is different than a straight push cut vs a slight slicing motion when contacting the board. People have used string extended over a platform on a scale, and taring the platform’s weight measured the point where the string is cut. This is fraught with string consistency issues, string tension issues, matching the string performance to the force range of the cut and variance along the edge, etc.

In a practical but imperfect sense, I use the ability of a knife to slice or push cut through copy paper as one index. For push cuts it is a direct downward motion perpendicular and from a point of touching the paper. I measure how far out from a pinch grip it will do this, eg push cutting 2 inches from a pinch grip. There are ways to cheat on this and edge thickness and angles change the values for equally sharpened edges. Ultimately the ideal test of sharpness is done by using the knife for it’s intended task.

Not all knives are sharpened the same along their whole length, so ultimately you have to sample along the whole length. So for instance, a deba might have a less acute angle at it’s heel than it’s tip because the heel is used for chopping off fish heads and the tip and midsection for filleting the fish so the angle is varied along it’s length in a continuously variable fashion. This CAN be done with a WE.

Sharpness is not the only goal involved in sharpening a knife. You trade for longevity of the edge, the task it will be used for and so forth. In some instances aesthetic considerations may even exceed sharpness requirements. This is a topic in itself, which can take into account both personal and cultural aesthetics. In some instances like shaving, comfort may be of equal importance to sharpness.

This doesn’t even begin a discussion of defining sharpness.

—
Ken

Quote from Ken “… I thought I knew what sharp was, but I have proven myself wrong so many times that now I just look forward to reaching the next level.”

Ken, Your statement above caught my eye.. how have you established that one blade is sharper than another? has anyone been able to get there hands on and loan us one of these ? Actually have one on order myself, it is due to be delivered just after I win the next Mega-Lotto

http://www.catra.org/pages/products/kniveslevel1/surgredst.htm B)

[Leo James Mitchell]

For me there is also great satsifaction just knowing my knife is so crazy sharp and I made it that way…there is a kind of male pride knowing this. I suppose it may have something to do with a sense of manliness that harkens back to the days when a sharp knife was an indispensible tool necessary for life.This may flow from my limbic brain!! LOL!
Well done Ken! I really enjoyed your commentary, most pertinent!

Best regards
Leo

[BassLake Dan]

For me there is also great satsifaction just knowing my knife is so crazy sharp and I made it that way…there is a kind of male pride knowing this. I suppose it may have something to do with a sense of manliness that harkens back to the days when a sharp knife was an indispensible tool necessary for life.This may flow from my limbic brain!! LOL!
Well done Ken! I really enjoyed your commentary, most pertinent!

Best regards
Leo

Yes i agree Leo that Kens Quote above is a classic and very well stated.. I am going to print it out for future reference. Actually I think it is so well done that it needs to be in some sort of Reference Archive here on the board!

As for your man-cave perspective well :woohoo: don’t look over your shoulder, as something might be gaining on you, and her knife might be sharper than yours !!!!

[Leo James Mitchell]

Yes I agree that knowledge like this should be kept somehow on this forum in a safe reference area…I shall speak to Clay about that and see if it can be done.
As for her gaining on me, let her come! My knife is bound to be sharper than her knife, but maybe not as sharp as her tongue!! Whoops! I will pay for that I have a feeling! LOL!

Leo

[Jende Industries]

+1 on everything Ken said!!!

And we haven’t even touched the subject of aesthetic polishing vs. establishing “true” grit edges! 👿

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