I look at it as 'being so proud of winning a Gold Medal, that you have it bronzed...'
Stitchawl
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RE Stropping
- Thread starter Sadden
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I look at it as 'being so proud of winning a Gold Medal, that you have it bronzed...'
Stitchawl
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Hah! If I was still a paying member, I'd make that my new sig line, Stichawl. 
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Well for starters I never said that Roo Leather contains more silicates than bovine or equine , although this is kind of a moot point as I am about to discuss.
A) Ken does not split his Kangaroo Leather. I just confirmed that over the phone this morning.
B) The silicates in any leather have very little if any abrasive effect whatsoever the bare Roo leather strop at the top of this thread has been used quite a bit , and yet I see hardly any metal deposit at all. The silicates tend to cause more of a burnishing effect , which is a totally different topic , if your interested in that then I would suggest doing some reading over at wicked edge forums , Clay has done some interesting testing regarding the subject.
C) The reason that you want a leather with fine silicates is that you don't want the silicates interfering with whatever compound you choose to use that strop for. HH and I briefly discussed this earlier in the thread. And he was right on the money. You want a leather with fine pores so it does a better job of presenting abrasive instead of hiding it.
Again , what makes kangaroo leather the best for stropping is the fact that its the thinnest leather , with the smallest silicates.
A) Ken does not split his Kangaroo Leather. I just confirmed that over the phone this morning.
B) The silicates in any leather have very little if any abrasive effect whatsoever the bare Roo leather strop at the top of this thread has been used quite a bit , and yet I see hardly any metal deposit at all. The silicates tend to cause more of a burnishing effect , which is a totally different topic , if your interested in that then I would suggest doing some reading over at wicked edge forums , Clay has done some interesting testing regarding the subject.
C) The reason that you want a leather with fine silicates is that you don't want the silicates interfering with whatever compound you choose to use that strop for. HH and I briefly discussed this earlier in the thread. And he was right on the money. You want a leather with fine pores so it does a better job of presenting abrasive instead of hiding it.
Again , what makes kangaroo leather the best for stropping is the fact that its the thinnest leather , with the smallest silicates.
It appears, from this photo alone, that he doesn't case and process the leather either. That means it can't be nearly dense enough to make a high quality strop. The very best "Russian Leather" strops 'were' made (because the process is too costly today) from horsehide that was pounded and pulled for several days, compressing the leather into rock-hard but yet flexible material, with the silicates pressed to the surface.
I agree that you don't see any metal deposit on your roo leather strop. But you should see the black surfaces of my bare leather strops, especially the horsehide strops! The silicates in a 'properly prepared' strop have a wonderfully abrasive quality at an extremely fine grit size. The operative words being 'properly prepared.' This is why barbers have been using horsehide strops for the past several HUNDRED YEARS. And why these strops turn black.
Clay isn't the only one who has done testing with interesting results. Rather than read about the tests, I did them myself. And I'm sorry to say that you and I disagree completely on most of what you have written... except the part about your strop not showing any metal buildup.
Natural silicates in leather are always 'fine.' That's why we use it as the last step in the sharpening process. As to covering up these high quality abrasives... no thanks. Why waste them? Then spend a lot of money on a compound with grit size the same as the silicate size? Makes no sense.
Fine pores? What? If you want your compound to stay on top, put it on MDF. I guarantee it will stay on top. You don't need to spend the money on the leather. However, every manufacturer needs you to spend money on his product. There was a borosilicate glass 'steel' being sold for $70 a while ago. I had my custom made at a local chemical supply shop (borosilicate glass is 'Pyrex,' the stuff they make test tubes out of, or the glass pie plates and meat loaf pans on the supermarket shelves) for under $10. No difference in the glass he was selling and the glass I was using... except $60. He's a manufacturer. He needs people to buy is goods. And he wants to make a profit. Make something sound exotic, put a high price on it, and people will buy it.
You might want to take a primer on the basics of leather. Natural silicates enter the animal's body via the food (vegetable matter) it eats. The silicates in HUMAN skin are the SAME SIZE as the silicates in ANY animal's skin. A person on a vegetarian diet will have a higher concentration of silicates in his/her skin than a person who also eats meats and poultry because the foods they eat are higher in silicates. (People, please do NOT begin harvesting stropping material from your neighborhood Vegans!)
If you want thin leather, use the belly cut of doe skin. Now that is thin! So thin, in fact, that people use this for cleaning their eyeglasses. Don't use the shoulder cut or the neck cut though... Those are thicker. Depending on which part of the skin is used, the thickness can vary from more than 3/8" down to less than 1/16". Older animals will have thicker skin than younger ones. Elk has thicker skin than deer. I have a piece of Orthopedic Elk hide that is more than 3/8" thick, and a piece of cowhide that is less than 1/16". But hides aren't measured in inches or thickness. They are measured in ounces... You can purchase leather that is down to 2-3oz. That is usually used as lining leather for wallets, bags, and clothing.
But... any vegetable tanned leather 'can' be made thinner and much more dense by 'properly processing' it before use as a strop, just as the old 'Russian' Leather strops of 100 years ago. (Russian Leather is the term used for the process, rather than the country of origin.) We can take a piece of thick shoulder cut vegetable tanned cowhide 8-10oz, and by casing it and rolling/pounding it, make it as thin as that quarter in your photo. It will be so dense that you almost can't score it with your fingernail. And, because the silicates will have migrated to the surface during the processing, will make a strop that will keep a shaving edge on any blade, and if treated correctly, this strop will last a lifetime... or two.
You don't have to believe what I say. And that's OK. But please do your own testing and find out for yourself. I have.
Stitchawl
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Hi Stitchawl,
That's a lot of interesting information and I agree with the majority of what you are saying, especially the processing techniques employed (Russian leather techniques, etc). That doe skin does sound interesting. I guess the point of the discussion I find missing is comparing silicates in terms of Mohs hardness compared to CBN or other abrasive compounds. There is some abrasive content to the Kangaroo, not a lot, but more than the nanocloth. So the difference is that you are referring to processes that supposedly increase the surface concentration of these fine silicates. I will accept that as your expertise. So using the approach, you are entirely relying on these silicates for abrasion. It isn't an unreasonable approach. But there are other approaches.
So with Kangaroo, you can use it without compound for good effect. BUT, and I would suggest you try it, here when using compounds we are not relying on these silicates. Indeed if there were NO silicates, it would be even better. This is the case with nanocloth. We are using the applied abrasives instead, wanting as close to a neutral substrate as possible. They cut far faster. Of course, coarser grits do cut faster. But the finer ones also cut far faster than leather alone. So, for instance using compounds finer or as fine as a tenth micron I would recommend you compare your edges off of say a Russian leather to a Kangaroo strop with a tenth micron CBN or 0.025 micron Polycrystalline diamond treated strop to them. I use this as my final strop and it greatly exceeds the results I get from any other strop I've used. If barbers had this hundreds of years ago ... Well 50 years ago the Japanese did use Chromium oxide.
Don't think of it as A1 sauce. Think of it more like a Périgueux sauce prepared with fresh truffles over an exquisite filet mignon
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Ken
That's a lot of interesting information and I agree with the majority of what you are saying, especially the processing techniques employed (Russian leather techniques, etc). That doe skin does sound interesting. I guess the point of the discussion I find missing is comparing silicates in terms of Mohs hardness compared to CBN or other abrasive compounds. There is some abrasive content to the Kangaroo, not a lot, but more than the nanocloth. So the difference is that you are referring to processes that supposedly increase the surface concentration of these fine silicates. I will accept that as your expertise. So using the approach, you are entirely relying on these silicates for abrasion. It isn't an unreasonable approach. But there are other approaches.
So with Kangaroo, you can use it without compound for good effect. BUT, and I would suggest you try it, here when using compounds we are not relying on these silicates. Indeed if there were NO silicates, it would be even better. This is the case with nanocloth. We are using the applied abrasives instead, wanting as close to a neutral substrate as possible. They cut far faster. Of course, coarser grits do cut faster. But the finer ones also cut far faster than leather alone. So, for instance using compounds finer or as fine as a tenth micron I would recommend you compare your edges off of say a Russian leather to a Kangaroo strop with a tenth micron CBN or 0.025 micron Polycrystalline diamond treated strop to them. I use this as my final strop and it greatly exceeds the results I get from any other strop I've used. If barbers had this hundreds of years ago ... Well 50 years ago the Japanese did use Chromium oxide.
Don't think of it as A1 sauce. Think of it more like a Périgueux sauce prepared with fresh truffles over an exquisite filet mignon
---
Ken
There certainly are other approaches, I agree. Regarding hardness of silicates and Mohs scale, of course diamonds are harder than silicates, but silicates are harder than steel. THAT is all that matters. For a 'final strop,' I completely rely on the natural silicates found in the leather. They are more than enough to finish an edge.
I'm afraid that it's right here... especially this last sentence, that causes me difficulty. I only take 8-10 strokes on a properly made horsehide strop to finish my edge. 15-20 seconds. How much faster do I need? Save 4 seconds but spend $75 to do so?
Why would it be 'even better' to use a substrate with no abrasive, then ADD abrasive, to create what I already have with properly processed leather at 1/10 the cost?
I'm certainly willing to concede that the edges will be quite similar. The silicates often run that small in better horsehide or cowhide strops, and of course if you are using Kangaroo leather with a fine grit Polycrystalline diamond compound, you will get good results....
But...
The average shopper can buy a 12"x12" square of good vegetable tanned leather on line for under $15 and with 30 minutes work have FOUR STROPS (not just one) that give an edge as good as the Kangaroo leather and Polycrystalline diamond compound, which together cost.... what? SEVENTY FIVE DOLLARS? Or more?
I can understand someone who sells this stuff wanting to create the aura of the 'magic sword Excaliber.' That what sales people need to do to move an expensive product. Or the Emperor's New Clothes. And even when the product is very good, which many of the Polycrystalline diamond compounds are, there is a need to justify the huge expense somehow. But me, as a knowledgeable consumer who has already used polycrystalline diamond compounds knows, for a final strop, they just aren't needed. For someone who wants to use a strop like a stone, and spend 30 minutes to an hour stropping, rather than working the edge on stones, the Polycrystalline diamond compounds are certainly faster than other compounds. I strop for seconds rather than minutes. I'll stick with a properly processed shell cordovan horsehide strop. When it gets too glazed over with metal, I'll clean it again as I've done before. Many times over the years.
EDIT: After I posted, I went searching for Nano cloth. I guess I wasn't too surprised to see it being sold by the same company that sells the Polycrystalline diamond compound as strops. Are you related to that company some way?
2nd EDIT: I got to thinking about this, so I went back to that same web site and did a search for Kangaroo leather... Surprise! They are selling kangaroo leather strops too... I'm beginning to suspect that the entire post was simply an advertisement...
Stitchawl
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BluntCut MetalWorks
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I agree with both - Stitchawl & Ken - of you on most points because each approach has its best fit for a particular spec among vast combination of steels & ht. E.g. Russian prep leather probably work great for simple carbon or low alloy blades. While diamond(mono&poly)/cbn/bn provides appropriate abrading power for high alloy blades, such as s90v; s110v;k390;cpm-rex;... And the user need to pick best approach for in between situations.
Market speak: Russian style-prep leather is fading to non-existence, perhaps demand mostly ceased. I doubt it's because of the cost, since this process can get done cheaply in cheap-labor countries. diamond/cbn on the rise because they are versatile abrasives that can abrade all combination of steel+ht - yeah jack of all trades. Ken's company offer high quality dia/cbn/leather/nano/stones(big+ep)/ blah products at premium prices. For informed + skills
users, we can go cheap dia/cbn/etc.. route and get same result. keep in mind, Ken's Co doesn't manufacture their own abrasive but rather value-add and oem in some products.
I try to stay neutral/balance on both view points, since Ken can't provide more in depth counter point while walking to BF rule plank.
Market speak: Russian style-prep leather is fading to non-existence, perhaps demand mostly ceased. I doubt it's because of the cost, since this process can get done cheaply in cheap-labor countries. diamond/cbn on the rise because they are versatile abrasives that can abrade all combination of steel+ht - yeah jack of all trades. Ken's company offer high quality dia/cbn/leather/nano/stones(big+ep)/ blah products at premium prices. For informed + skills
users, we can go cheap dia/cbn/etc.. route and get same result. keep in mind, Ken's Co doesn't manufacture their own abrasive but rather value-add and oem in some products.I try to stay neutral/balance on both view points, since Ken can't provide more in depth counter point while walking to BF rule plank.
Well the topic has reached an impass. Clearly if my point was to sell you, I would have failed. It isn't. It is simply to correct what I perceive as misconceptions and some circular reasoning to support an entrenched point of view without sufficient data. I do find your describing me as a seller of Emperor's clothes, magic elixers etc not a very convincing way of winning points in a discussion, bordering on an ad hominem argument rather than a logical one. Let me be more specific.
"...diamonds are harder than silicates, but silicates are harder than steel. THAT is all that matters. For a 'final strop,' I completely rely on the natural silicates found in the leather. They are more than enough to finish an edge...."
It really isn't all that matters. If it was we would all be using silicates as abrasives for everything. We don't. There are several forms of aluminum oxide, silicon carbide and other abrasives like CBN Boron Carbide and various forms of diamond, to say nothing of a variety of natural stones. They are used to achieve various results. Most silicates are in the range of 6-7 on the Moh's hardness scale. That it meets your needs is fine. It doesn't always meet mine. It's unclear if you are arguing this from a point of function or price. If your results meet your needs from a point of view of price I concede the point that you should not spend more money for a solved problem. If you feel that you have argued that it is a superior approach in terms of function, here I disagree.
" How much faster do I need? Save 4 seconds but spend $75 to do so?" How about zero seconds? I would argue that having achieved an edge that IMO I find superior to a finish stopping at a Russian leather strop is degrading the edge I can achieve. It is going backwards for me. Here we may simply agree to disagree. I have tried both and this is the data I have to support my argument. If you have actually tried both approaches AT THE LEVEL OF PARTICLE SIZE being discussed, then we have a difference in interpretation. If not then you have insufficient data to support your conclusions, hence my assertion that you are supporting an entrenched point of view with insufficient data.
"For someone who wants to use a strop like a stone, and spend 30 minutes to an hour stropping, rather than working the edge on stones ..." If you are implying this is my approach, you are quite inaccurate. I routinely strop with a kangaroo strop WITH compound and am done doing this before the tap water is warm enough to shave. The idea of going from a stone of say 10-15k to a strop surface with weak very fine abrasive purportedly in the range of greater than 600k grit [references ?] is too weak of an approach to produce what I consider an ideal edge for my needs. If this is your approach and it works for you, please continue.
---
Ken
"...diamonds are harder than silicates, but silicates are harder than steel. THAT is all that matters. For a 'final strop,' I completely rely on the natural silicates found in the leather. They are more than enough to finish an edge...."
It really isn't all that matters. If it was we would all be using silicates as abrasives for everything. We don't. There are several forms of aluminum oxide, silicon carbide and other abrasives like CBN Boron Carbide and various forms of diamond, to say nothing of a variety of natural stones. They are used to achieve various results. Most silicates are in the range of 6-7 on the Moh's hardness scale. That it meets your needs is fine. It doesn't always meet mine. It's unclear if you are arguing this from a point of function or price. If your results meet your needs from a point of view of price I concede the point that you should not spend more money for a solved problem. If you feel that you have argued that it is a superior approach in terms of function, here I disagree.
" How much faster do I need? Save 4 seconds but spend $75 to do so?" How about zero seconds? I would argue that having achieved an edge that IMO I find superior to a finish stopping at a Russian leather strop is degrading the edge I can achieve. It is going backwards for me. Here we may simply agree to disagree. I have tried both and this is the data I have to support my argument. If you have actually tried both approaches AT THE LEVEL OF PARTICLE SIZE being discussed, then we have a difference in interpretation. If not then you have insufficient data to support your conclusions, hence my assertion that you are supporting an entrenched point of view with insufficient data.
"For someone who wants to use a strop like a stone, and spend 30 minutes to an hour stropping, rather than working the edge on stones ..." If you are implying this is my approach, you are quite inaccurate. I routinely strop with a kangaroo strop WITH compound and am done doing this before the tap water is warm enough to shave. The idea of going from a stone of say 10-15k to a strop surface with weak very fine abrasive purportedly in the range of greater than 600k grit [references ?] is too weak of an approach to produce what I consider an ideal edge for my needs. If this is your approach and it works for you, please continue.
---
Ken
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Just to be clear if you believe that the silicates in all leather are 0.01 micron approx. 1,600,000 grit , then what are you using leading up to that? Even jumping from a 30k shapton isn't anywhere near close enough.
If there are so many silicates in leather , why do you need to "bring them to the top"? Which is and of itself contradictory , I have yet to see any evidence that this preparation moves silicates through the leather to the working portion of the strop. Its just illogical , how can you pull something through leather like that. It would be like trying to pull a grain of sand through to the top of a blanket using a rolling pin....
I can agree that creating a denser leather is beneficial , less convexing etc. But why would I invest my time to do that , when I work 80+ hours a week , when I can just use kangaroo leather which is already thinner and finer than the prepared Russian leather?
Another interesting point is what is the particle size distribution of the silicates found in leather? Being a natural product they are not going to be a uniform size or shape. Nor even a uniform abrasive , there are many different forms of silicates , not all of which are hard enough to abrade steel effectively.
Additionally , do you have any references in regards to the actual size and/or particle size distribution of the natural silicates found in leather?
If there are so many silicates in leather , why do you need to "bring them to the top"? Which is and of itself contradictory , I have yet to see any evidence that this preparation moves silicates through the leather to the working portion of the strop. Its just illogical , how can you pull something through leather like that. It would be like trying to pull a grain of sand through to the top of a blanket using a rolling pin....
I can agree that creating a denser leather is beneficial , less convexing etc. But why would I invest my time to do that , when I work 80+ hours a week , when I can just use kangaroo leather which is already thinner and finer than the prepared Russian leather?
Another interesting point is what is the particle size distribution of the silicates found in leather? Being a natural product they are not going to be a uniform size or shape. Nor even a uniform abrasive , there are many different forms of silicates , not all of which are hard enough to abrade steel effectively.
Additionally , do you have any references in regards to the actual size and/or particle size distribution of the natural silicates found in leather?
When I first replied to your post, I was unaware that YOU were the seller of these products. I wasn't attacking you. I was ridiculing the outrageous cost and claims of an un-needed product. In my first edit I said that I found one website selling the nano cloth and compounds. I then asked if you were involved with that site. I asked this because of your strong convictions that we needed to use these products if we wanted to get good results. I then had the idea to check for the kangaroo leather strops on that same site, and found them, leading me further to believe that you were in fact involved with that site, as what you were saying struck me more as advertisement for expensive products (NOTE: I'm not suggesting that these products are in any way inferior, only expensive and not usually necessary,) rather than information being presented for education. Later on I was told by a friend that you are, in fact, the owner of that site. Sorry if you took it personally.
I didn't say we'd use it for everything. I said it's more than enough to finish an edge. You are talking about 'various results,' as you say above. I said it's more than enough to finish an edge, not more than enough for everything. Obviously there are valid uses for different compounds.
Yes, that's probably a good idea.
I guess you didn't bother to read the line I wrote that said; "...But me, as a knowledgeable consumer who has already used polycrystalline diamond compounds knows, ...." Sometimes it pays to read before you respond.
I'm not implying anything. I'm stating a fact. And I'll re-state it. "For someone who wants to use a strop like a stone, and spend 30 minutes to an hour stropping, rather than working the edge on stones, the Polycrystalline diamond compounds are certainly faster than other compounds." Or are you now suggesting that Polycrystalline diamond compounds are NOT faster than other compounds?
You are selling products that work. You are selling products that are expensive. You are selling products that solve a problem.
But... there are other ways to solve the problem that are FAR less expensive and work just as well for most people. To suggest otherwise is doing a disservice to the buying public.
Most likely the 'typical person' who would want to use the ultra-fine Polycrystalline diamond compounds smaller than .02 micron will be those who are sharpening their straight razors, not their pocket knives or fixed blade knives. "Typical" being the operative word. That's a rather small demographic. The typical EDC carriers who want a sharp knife have no need or even desire of an edge taken to 150,000 grit. Most will be content at 4,000 or less. We've seen that time and again here, with many even stating that they stop sharpening at 400-600 grit. A few of us are more obsessive, and we might take our EDC edges to 10,000-15,000 grit. It behooves a merchant to create a need/desire to increase the size of that target demographic that would need to use an ultra-fine .02mic compound, especially at $65 for a small bottle, and $30 for a piece of leather or cloth.
Sorry, but I can get a good clean, comfortable shave with a bare strop that cost me less than five bucks.
Stitchawl
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This thread is waay off course from the OP's initial statement.
Why do you need to use a diamond spray compound with high carat rating rather than low carat rating?
It's clear that you need to do more research about the qualities of leather. I'll finish this thought below...
If you are going to slather on compound over the leather, and willing to spend $30-$50 on one strop, you're absolutely correct. There is no reason.
But...
If you would like to have four strops that work every bit as well (or better) with OR without compound than your thin Kangaroo leather, and are willing to spend a few minutes of time preparing them, there there IS a valid reason. Actually, if your Kangaroo leather hasn't been cased and rolled, then it's not nearly dense enough to call it a properly processed strop. It's just a thin piece of leather. On the up side, you do get to tell people you use Kangaroo leather, which certainly sounds better than cowhide...
Here's a simple test you can do yourself in less than 3 seconds... Try pressing your fingernail into your Kangaroo leather strop. If it makes a dent in the leather you will know instantly just how good your strop is. But I'm guessing you won't try this because you really don't want to know...
The internet is full of them. As I said before, you really need to do more research about the qualities of leather. You used a 'grain of sand through a blanket' example before thinking that this is something that can't be done. Haven't you ever spread a blanket on the sand at the beach? LOL! That is a perfect example of how the silicates migrate through the leather! I couldn't have thought of a better one!
Stitchawl
That's very true. But as it is the Original Poster who has changed the course of his own thread, it's probably not a problem for him.
Stitchawl
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I didn't actually read any of the posts in this thread. This thread has to hold the record for loooongest average post!
Well let me clear up a few misconceptions. I do sell nanocloth, Kangaroo leather and a bunch of other things too, including other leather and other stropping media. And sharpening stones, diamond films, etc etc. I personally use these products for sharpening and honing so I do speak from a point of view of personal experience. Indeed, when I recommend one approach or another, I am usually recommending one product at the expense of not recommending another product. One of the most important things I do in selling a product is EDUCATING my customers. I even recommend customers buying other people's products or not buying one of my products if I feel it won't best meet their needs. I also don't sharpen people's knives beyond what their knife is capable of. Why? In a word - INTEGRITY. I value my integrity FAR more than a sale and prefer to establish a relationship of trust in what I recommend. Do I have strong convictions about my products? Yes I am guilty of this. If I didn't I would consider it less than ethical to be selling what I don't believe in - regardless of the profit involved. I do accept your apology as feeling it was becoming somewhat personal, so let's go from there. What I am posting here is both for your education and others. As you sell / trade leather products, I would consider your responses as educational as my posts. Please don't impugn my motives as you hardly know me at all.
"I was ridiculing the outrageous cost and claims of an un-needed product." To be clear, this is your Opinion. It differs from mine, but it hardly rises to the level of being a fact. I have customers who have been using my products now for years who would strongly disagree with your Opinion on the matter. This includes people who have used my products, competitors' products and bare strops of all sorts. I hardly think it appropriate to 'ridicule' someone who has an opposing opinion. I will strive not to ridicule your opinions and hope we can discuss this in a less ridiculing manner.
When it comes to just finishing an edge, your Opinion is one of many, as is mine. Some feel quite content with a 8k edge (not me), Some with various European stones (Eschers, coticules, etc), and some insist that only a Japanese natural stone like a Nakayama Asagi or Kiita or Iromono will do. Some of these stones FAR exceed the cost of a strop, yet perhaps this is a bone of contention on your part as well?
Cost seems to be a major issue with you. I see Russian leather strops in excess of $100 on the net too. Should we only consider what YOU feel is an appropriate amount to spend on these strops?
Regarding the use of compound. On the strops we are discussing here - 1x6" in size a SINGLE DROP is enough to coat them. This one drop will last for MANY honing / sharpening sessions. I can easily get well over 50 honings on a single application. At this rate one bottle will last me YEARS for final finishing applications on a bench strop. If you want to do the math consider the number of drops in 2 ounces and multiply it by 50 and divide it by the cost of a bottle. This translates to pennies, perhaps fractions of a penny per honing.
If you wish to save even more money, consider using paper instead of any leather. Placed over glass they present a surface harder than Russian leather or Kangaroo. Over a softer substrate, they are ideal for more convex edges. You do know that paper contains silicates as well. In fact both the plant material in paper and to an extent, the silicates brought in by the water used in paper production contain silicates too. This material is pressed and rolled too, with various hardnesses and finishes. Should we say that using Russian technique treated leather is 'ridiculous' and an unneeded product, ridiculously expensive compared to copy paper or the newspaper used for years in Japan for final finishing? FWIW, for final finishing, I do use paper as well and I prefer paper with less abrasive properties rather than something loaded up with silicates. A more pricey paper is made by Rhodia and Clairfontaine (I have NO commercial interest in these paper mills ), but if as it seems you are on a more extreme budget, so consider bagassee based paper, made from sugar cane pulp (again no commercial interest here either). For many coarser applications, simple copy paper will do. My compounds work quite well on any of these choices. They just work better on the other strops mentioned here. I neither insist that my compounds be used on a particular substrate or that the substrates I provide must be used with my compounds.
FWIW I do not have my own website at this time. My products are available directly from me or on others' websites.
"I guess you didn't bother to read the line I wrote that said; "...But me, as a knowledgeable consumer who has already used polycrystalline diamond compounds knows, ...." Sometimes it pays to read before you respond."
Sometimes it pays to read what I wrote more carefully too. I even capitalized it to help. "AT THE LEVEL OF PARTICLE SIZE being discussed," If you have tried particles sizes below tenth micron, then please accept my apologies. Otherwise please read more carefully.
"I'm not implying anything. I'm stating a fact. And I'll re-state it. "For someone who wants to use a strop like a stone, and spend 30 minutes to an hour stropping, rather than working the edge on stones, the Polycrystalline diamond compounds are certainly faster than other compounds." Or are you now suggesting that Polycrystalline diamond compounds are NOT faster than other compounds? "
Again, read more carefully. I am saying that that is not my approach. While poly does cut faster than other abrasives, depending on the steel etc., that isn't what I was discussing. What I was discussing is that stones are not going finer than 30,000 grit and most finish using stones at 8 - 15k. So to suggest that a weaker abrasive present in 'Russian' Leather' that is up at 1.5 million grit is an optimum jump from even a 15 k stone is a HUNDRED FOLD jump in grit size! Suggesting that this is OPTIMAL should be something to ridicule, but let me just say that we have a difference of opinion in the matter. I certainly would like to see a well referenced source for this data regarding leather silicate sizes, as I was unable to find this. Please read this a bit more carefully - I said well referenced, not hearsay. I also would like a reference describing how the Russian leather treatment brings these silicates to the surface - again not hearsay. Since these silicates are so small, scanning electron micrographs would be useful here. If you have this level of expertise, and if you have information about WHICH silicates are present in leather and what the shapes are of these particulates, that would also be useful. The flaw in your statement is that your conclusion, which is largely correct, has no relation to your premise. It is a misleading statement.
"You are selling products that work. You are selling products that are expensive. You are selling products that solve a problem.
But... there are other ways to solve the problem that are FAR less expensive and work just as well for most people. To suggest otherwise is doing a disservice to the buying public."
Again this is opinion not fact. You are entitled to your opinions. Diamond and CBN is more expensive than a strop alone, but not expensive on a per use basis. This has been tested. So are diamond films, Japanese natural stones, etc more expensive than Russian leather, but more expensive than paper. It is your Opinion that your approach works just as well - one I disagree with. What I am doing is hardly a disservice. It is simply IMO stating the results of my years of study. I could equally as well say that your points are equally a disservice to those that know better. I have photographs and micrographs to back it up. What do you have - mostly unsupported hearsay? You really have not laid out a convincing argument yet.
"Most likely the 'typical person' who would want to use the ultra-fine Polycrystalline diamond compounds smaller than .02 micron will be those who are sharpening their straight razors, not their pocket knives or fixed blade knives. "Typical" being the operative word. That's a rather small demographic. The typical EDC carriers who want a sharp knife have no need or even desire of an edge taken to 150,000 grit. Most will be content at 4,000 or less. We've seen that time and again here, with many even stating that they stop sharpening at 400-600 grit. A few of us are more obsessive, and we might take our EDC edges to 10,000-15,000 grit. It behooves a merchant to create a need/desire to increase the size of that target demographic that would need to use an ultra-fine .02mic compound, especially at $65 for a small bottle, and $30 for a piece of leather or cloth. "
So your argument is to follow these 'typical' users edges with a surface of 1.5 million grit or so instead? That makes no sense whatsoever. I much prefer to select a grit level appropriate for the task at hand. The task might be best served with an 80 micron compound, a stone, etc etc. It should be obvious to you that not all applications would benefit from 25 nanometer (not 20 as you state) levels of finish - or a Russian leather strop either.
I doubt I will convince you of a thing - let alone a sale. But letting inaccurate statements (Opinions, not facts] of either me or my products go unchallenged is something deserving a response, even though I could be doing something else than writing long posts. I consider this education. So I'm off to do a bit more research and continue to develop new products and study knowledge that has almost been forgotten by Japanese craftsman from long ago.
---
Ken
"I was ridiculing the outrageous cost and claims of an un-needed product." To be clear, this is your Opinion. It differs from mine, but it hardly rises to the level of being a fact. I have customers who have been using my products now for years who would strongly disagree with your Opinion on the matter. This includes people who have used my products, competitors' products and bare strops of all sorts. I hardly think it appropriate to 'ridicule' someone who has an opposing opinion. I will strive not to ridicule your opinions and hope we can discuss this in a less ridiculing manner.
When it comes to just finishing an edge, your Opinion is one of many, as is mine. Some feel quite content with a 8k edge (not me), Some with various European stones (Eschers, coticules, etc), and some insist that only a Japanese natural stone like a Nakayama Asagi or Kiita or Iromono will do. Some of these stones FAR exceed the cost of a strop, yet perhaps this is a bone of contention on your part as well?
Cost seems to be a major issue with you. I see Russian leather strops in excess of $100 on the net too. Should we only consider what YOU feel is an appropriate amount to spend on these strops?
Regarding the use of compound. On the strops we are discussing here - 1x6" in size a SINGLE DROP is enough to coat them. This one drop will last for MANY honing / sharpening sessions. I can easily get well over 50 honings on a single application. At this rate one bottle will last me YEARS for final finishing applications on a bench strop. If you want to do the math consider the number of drops in 2 ounces and multiply it by 50 and divide it by the cost of a bottle. This translates to pennies, perhaps fractions of a penny per honing.
If you wish to save even more money, consider using paper instead of any leather. Placed over glass they present a surface harder than Russian leather or Kangaroo. Over a softer substrate, they are ideal for more convex edges. You do know that paper contains silicates as well. In fact both the plant material in paper and to an extent, the silicates brought in by the water used in paper production contain silicates too. This material is pressed and rolled too, with various hardnesses and finishes. Should we say that using Russian technique treated leather is 'ridiculous' and an unneeded product, ridiculously expensive compared to copy paper or the newspaper used for years in Japan for final finishing? FWIW, for final finishing, I do use paper as well and I prefer paper with less abrasive properties rather than something loaded up with silicates. A more pricey paper is made by Rhodia and Clairfontaine (I have NO commercial interest in these paper mills
), but if as it seems you are on a more extreme budget, so consider bagassee based paper, made from sugar cane pulp (again no commercial interest here either). For many coarser applications, simple copy paper will do. My compounds work quite well on any of these choices. They just work better on the other strops mentioned here. I neither insist that my compounds be used on a particular substrate or that the substrates I provide must be used with my compounds.FWIW I do not have my own website at this time. My products are available directly from me or on others' websites.
"I guess you didn't bother to read the line I wrote that said; "...But me, as a knowledgeable consumer who has already used polycrystalline diamond compounds knows, ...." Sometimes it pays to read before you respond."
Sometimes it pays to read what I wrote more carefully too. I even capitalized it to help. "AT THE LEVEL OF PARTICLE SIZE being discussed," If you have tried particles sizes below tenth micron, then please accept my apologies. Otherwise please read more carefully.
"I'm not implying anything. I'm stating a fact. And I'll re-state it. "For someone who wants to use a strop like a stone, and spend 30 minutes to an hour stropping, rather than working the edge on stones, the Polycrystalline diamond compounds are certainly faster than other compounds." Or are you now suggesting that Polycrystalline diamond compounds are NOT faster than other compounds? "
Again, read more carefully. I am saying that that is not my approach. While poly does cut faster than other abrasives, depending on the steel etc., that isn't what I was discussing. What I was discussing is that stones are not going finer than 30,000 grit and most finish using stones at 8 - 15k. So to suggest that a weaker abrasive present in 'Russian' Leather' that is up at 1.5 million grit is an optimum jump from even a 15 k stone is a HUNDRED FOLD jump in grit size! Suggesting that this is OPTIMAL should be something to ridicule, but let me just say that we have a difference of opinion in the matter. I certainly would like to see a well referenced source for this data regarding leather silicate sizes, as I was unable to find this. Please read this a bit more carefully - I said well referenced, not hearsay. I also would like a reference describing how the Russian leather treatment brings these silicates to the surface - again not hearsay. Since these silicates are so small, scanning electron micrographs would be useful here. If you have this level of expertise, and if you have information about WHICH silicates are present in leather and what the shapes are of these particulates, that would also be useful. The flaw in your statement is that your conclusion, which is largely correct, has no relation to your premise. It is a misleading statement.
"You are selling products that work. You are selling products that are expensive. You are selling products that solve a problem.
But... there are other ways to solve the problem that are FAR less expensive and work just as well for most people. To suggest otherwise is doing a disservice to the buying public."
Again this is opinion not fact. You are entitled to your opinions. Diamond and CBN is more expensive than a strop alone, but not expensive on a per use basis. This has been tested. So are diamond films, Japanese natural stones, etc more expensive than Russian leather, but more expensive than paper. It is your Opinion that your approach works just as well - one I disagree with. What I am doing is hardly a disservice. It is simply IMO stating the results of my years of study. I could equally as well say that your points are equally a disservice to those that know better. I have photographs and micrographs to back it up. What do you have - mostly unsupported hearsay? You really have not laid out a convincing argument yet.
"Most likely the 'typical person' who would want to use the ultra-fine Polycrystalline diamond compounds smaller than .02 micron will be those who are sharpening their straight razors, not their pocket knives or fixed blade knives. "Typical" being the operative word. That's a rather small demographic. The typical EDC carriers who want a sharp knife have no need or even desire of an edge taken to 150,000 grit. Most will be content at 4,000 or less. We've seen that time and again here, with many even stating that they stop sharpening at 400-600 grit. A few of us are more obsessive, and we might take our EDC edges to 10,000-15,000 grit. It behooves a merchant to create a need/desire to increase the size of that target demographic that would need to use an ultra-fine .02mic compound, especially at $65 for a small bottle, and $30 for a piece of leather or cloth. "
So your argument is to follow these 'typical' users edges with a surface of 1.5 million grit or so instead? That makes no sense whatsoever. I much prefer to select a grit level appropriate for the task at hand. The task might be best served with an 80 micron compound, a stone, etc etc. It should be obvious to you that not all applications would benefit from 25 nanometer (not 20 as you state) levels of finish - or a Russian leather strop either.
I doubt I will convince you of a thing - let alone a sale. But letting inaccurate statements (Opinions, not facts] of either me or my products go unchallenged is something deserving a response, even though I could be doing something else than writing long posts. I consider this education. So I'm off to do a bit more research and continue to develop new products and study knowledge that has almost been forgotten by Japanese craftsman from long ago.
---
Ken
Please forgive me taking the liberty to move your last paragraph to the top, as well as some of your other 'statements,' for no other reason than clarity.
Absolutely! Which is why I'm even taking the time, albeit this long one, to respond. You didn't reply to what I wrote. You seem to take a lot of liberties deciding what I'm thinking....
You replied to what you felt, as illustrated in the following;
Where in my statement does it say anything about YOU or your approach? Making this incorrect assumption, you finish with;
The flaw in your statement is that your conclusion, which is largely correct, has no relation to your premise. It is a misleading statement.
There is nothing misleading about my statement. Taken as I wrote it, it's a statement of fact.
The only misleading is you thinking it has something to do with you.
I'm not really sure how you define a 'fact,' but if people are able to get a clean, comfortable shave using $5 items, then to my way of thinking, spending $75-$100 for the same items is both outrageous and un-needed. I'm not saying that their shave might not be more comfortable using your products. I'm saying that for the past few hundred years folks have been satisfied with the shaves they've been getting every morning without spending a lot of money. That's a fact!
Not so much in actual dollars, but rather in wasted dollars. If there is something that I need, I'll buy it regardless of the price tag. On the other hand, I won't spend a nickel on snake oil.
If in fact they are actually genuine Russian leather horsehide strops, then they are worth the money to anyone who wants the very best strop made. That is, if in fact they have been processed as Russian leather rather than just given the name. There is a rather famous strop vendor who was selling bench strops calling them 'Russian Red Leather' brand strops.
I'll state this as a fact: Any vendor selling strops using leather that hasn't been cased and compressed is doing his customers a disservice. Just taking a piece of leather and cutting it to size and gluing it onto a pretty piece of wood, should be telling his customers that what he is selling is just plain leather glued to a base, rather than calling it a leather strop.
How about these strops you sell? If you press your fingernail into them, will it leave an indentation? Or is the leather processed well enough, dense enough to stand this simple test?
Er.... what gives you the idea that I sell or trade leather products? You've made so many different assumptions in your post it's hard to keep track of them all!
Another assumption? No, it's not a bone of contention for me. In fact, having lived in Japan for more than 20 years, in the Kyoto region, I used to buy my stones directly from the mine-owning families in Arashiyama. When commercial mining stopped being viable, the families continued to sell odd-shaped stones from their front porches along Rt.162 in the mountains north of Arashiyama.
One drop... You are using a 1x6" strop as a bench strop?
Or should we think 4x12" instead for your bench strop, meaning 8-10 drops? I wonder how many drops Joe Average uses, and how often HE reapplies? I keep reading about people going though bottles of diamond compound rather quickly. I guess they need to read your posts.
I don't wish to save more money. I just don't want to waste more money.
Almost everything on our planet contains silicates. It the single most common material, found in any and all living things, and as part of the chemistry of many non-living things.
Two points here; first, well made paper is an excellent stropping material, as has been discussed here often. Lots of folks strop on card stock, magazine paper, etc., BUT... for some reason, the Russian leather strops give a better final edge. Go figure...
Next, in 20 years living in Japan and involved with Japanese knife collectors, knife makers in Sakai, Osaka, knifeknuts, etc., and 15 years attending the wonderful Seki City Knife festival each October, I've never seen any Japanese ever use newspaper to do a final stropping. Not to suggest it never happens, but one would imagine that with my interest in knives I would have seen it at least once in 20 years, right? Not for final stropping. For testing their edges, sure. But not final stropping. They use properly prepared horsehide.
I'll accept your apologies.
You're absolutely correct. But just who suggested this jump? I don't recall seeing it anywhere...
Wait... Are you assuming again? Oh oh....
No experienced knifeknut would think that you could go straight from a stone to a bare strop. That's why God created compounds with different grits!
Well, when 'Sadden' gets done with his leather research, perhaps he'll share the links with you. They certainly aren't something that I keep on hand just in case someone asks me for them.
Thanks!
But in fact, they have been working well for people for several hundred years. That's not an opinion. That is fact. And they've cost a lot less. That is not an opinion. That is fact. What IS my opinion (and certainly can NOT say they are facts as I've never tried them,) are my comments in the first line that said; You are selling products that work. You are selling products that are expensive. You are selling products that solve a problem.
And you're correct, this IS just opinion on my part.
You are entitled to your opinions.
'Sigh'... More assumptions.... I'm not trying to convince YOU of anything. I don't give a hoot if you believe me or not. I'm hoping that people without an actual need, don't waste large sums of money that could perhaps be more wisely spent. Someone commuting 10 miles to work and back, through the middle of the city, would not need to buy a Lamborghini or Maserati. A Ford, Toyota, or even a Hyundai would work perfectly for them. 10 mile commutes through a city with a super high performance engine would not be mechanically healthy for those cars, and a waste of money. Might be a nice 'brag' piece, or fun to own, but certainly not value for money spent.
Was there some text that doesn't show up on my computer? Where do you get this stuff? Who said anything about jumping grit sizes?
Please... Stick to what is said. This is getting tedious.
Now it's getting redundant. You tried this route before, and I'm surprised you're trying it again. Here's the replay;
You said;
It really isn't all that matters. If it was we would all be using silicates as abrasives for everything. There are several forms of aluminum oxide, silicon carbide and other abrasives like CBN Boron Carbide and various forms of diamond, to say nothing of a variety of natural stones. They are used to achieve various results.
to which I replied;
I didn't say we'd use it for everything. I said it's more than enough to finish an edge. You are talking about 'various results,' as you say above. I said it's more than enough to finish an edge, not more than enough for everything. Obviously there are valid uses for different compounds.
... and now you try it again? Wow. As I said... tedious.
I wish you and your business well.
I've added my last post to this thread, but will be interested to hear about the 'fingernail test' results with your strops.
If you dare to post them...
Stitchawl
Absolutely! Which is why I'm even taking the time, albeit this long one, to respond. You didn't reply to what I wrote. You seem to take a lot of liberties deciding what I'm thinking....
You replied to what you felt, as illustrated in the following;
Where in my statement does it say anything about YOU or your approach? Making this incorrect assumption, you finish with;
The flaw in your statement is that your conclusion, which is largely correct, has no relation to your premise. It is a misleading statement.
There is nothing misleading about my statement. Taken as I wrote it, it's a statement of fact.
The only misleading is you thinking it has something to do with you.
I'm not really sure how you define a 'fact,' but if people are able to get a clean, comfortable shave using $5 items, then to my way of thinking, spending $75-$100 for the same items is both outrageous and un-needed. I'm not saying that their shave might not be more comfortable using your products. I'm saying that for the past few hundred years folks have been satisfied with the shaves they've been getting every morning without spending a lot of money. That's a fact!
Not so much in actual dollars, but rather in wasted dollars. If there is something that I need, I'll buy it regardless of the price tag. On the other hand, I won't spend a nickel on snake oil.
If in fact they are actually genuine Russian leather horsehide strops, then they are worth the money to anyone who wants the very best strop made. That is, if in fact they have been processed as Russian leather rather than just given the name. There is a rather famous strop vendor who was selling bench strops calling them 'Russian Red Leather' brand strops.
I'll state this as a fact: Any vendor selling strops using leather that hasn't been cased and compressed is doing his customers a disservice. Just taking a piece of leather and cutting it to size and gluing it onto a pretty piece of wood, should be telling his customers that what he is selling is just plain leather glued to a base, rather than calling it a leather strop.
How about these strops you sell? If you press your fingernail into them, will it leave an indentation? Or is the leather processed well enough, dense enough to stand this simple test?
Er.... what gives you the idea that I sell or trade leather products? You've made so many different assumptions in your post it's hard to keep track of them all!
Another assumption? No, it's not a bone of contention for me. In fact, having lived in Japan for more than 20 years, in the Kyoto region, I used to buy my stones directly from the mine-owning families in Arashiyama. When commercial mining stopped being viable, the families continued to sell odd-shaped stones from their front porches along Rt.162 in the mountains north of Arashiyama.
One drop... You are using a 1x6" strop as a bench strop?
Or should we think 4x12" instead for your bench strop, meaning 8-10 drops? I wonder how many drops Joe Average uses, and how often HE reapplies? I keep reading about people going though bottles of diamond compound rather quickly. I guess they need to read your posts.
I don't wish to save more money. I just don't want to waste more money.
Almost everything on our planet contains silicates. It the single most common material, found in any and all living things, and as part of the chemistry of many non-living things.
Two points here; first, well made paper is an excellent stropping material, as has been discussed here often. Lots of folks strop on card stock, magazine paper, etc., BUT... for some reason, the Russian leather strops give a better final edge. Go figure...
Next, in 20 years living in Japan and involved with Japanese knife collectors, knife makers in Sakai, Osaka, knifeknuts, etc., and 15 years attending the wonderful Seki City Knife festival each October, I've never seen any Japanese ever use newspaper to do a final stropping. Not to suggest it never happens, but one would imagine that with my interest in knives I would have seen it at least once in 20 years, right? Not for final stropping. For testing their edges, sure. But not final stropping. They use properly prepared horsehide.
I'll accept your apologies.
You're absolutely correct. But just who suggested this jump? I don't recall seeing it anywhere...
Wait... Are you assuming again? Oh oh....
No experienced knifeknut would think that you could go straight from a stone to a bare strop. That's why God created compounds with different grits!
Well, when 'Sadden' gets done with his leather research, perhaps he'll share the links with you. They certainly aren't something that I keep on hand just in case someone asks me for them.
Thanks!
But in fact, they have been working well for people for several hundred years. That's not an opinion. That is fact. And they've cost a lot less. That is not an opinion. That is fact. What IS my opinion (and certainly can NOT say they are facts as I've never tried them,) are my comments in the first line that said; You are selling products that work. You are selling products that are expensive. You are selling products that solve a problem.
And you're correct, this IS just opinion on my part.
You are entitled to your opinions.
'Sigh'... More assumptions.... I'm not trying to convince YOU of anything. I don't give a hoot if you believe me or not. I'm hoping that people without an actual need, don't waste large sums of money that could perhaps be more wisely spent. Someone commuting 10 miles to work and back, through the middle of the city, would not need to buy a Lamborghini or Maserati. A Ford, Toyota, or even a Hyundai would work perfectly for them. 10 mile commutes through a city with a super high performance engine would not be mechanically healthy for those cars, and a waste of money. Might be a nice 'brag' piece, or fun to own, but certainly not value for money spent.
Was there some text that doesn't show up on my computer? Where do you get this stuff? Who said anything about jumping grit sizes?
Please... Stick to what is said. This is getting tedious.
Now it's getting redundant. You tried this route before, and I'm surprised you're trying it again. Here's the replay;
You said;
It really isn't all that matters. If it was we would all be using silicates as abrasives for everything. There are several forms of aluminum oxide, silicon carbide and other abrasives like CBN Boron Carbide and various forms of diamond, to say nothing of a variety of natural stones. They are used to achieve various results.
to which I replied;
I didn't say we'd use it for everything. I said it's more than enough to finish an edge. You are talking about 'various results,' as you say above. I said it's more than enough to finish an edge, not more than enough for everything. Obviously there are valid uses for different compounds.
... and now you try it again? Wow. As I said... tedious.
I wish you and your business well.
I've added my last post to this thread, but will be interested to hear about the 'fingernail test' results with your strops.
If you dare to post them...
Stitchawl
Last edited:
BluntCut MetalWorks
Knifemaker / Craftsman / Service Provider
- Joined
- Apr 28, 2012
- Messages
- 3,462
Yes, the kangaroo leather strops sold by Ken do dent when a fingernail is pressed into them. The leather is very soft.
Did you get bad result when strop on bare roo leather?
For strop with compound, I use the nap/flesh side of leather (see balanced strop thread). So if you are using compound with roo, it might not matter.
For bare leather strop, I use the skin/smooth side of horse butt leather. Didn't dent my fairly heavy pressure finger nail pressed. I hardly use this 3x9.5 strop - says once per month. But if your roo strop works, then objective-achieved.
Yes, the kangaroo leather strops sold by Ken do dent when a fingernail is pressed into them. The leather is very soft.
That's a shame... a small piece of leather, and for so much money, too...
If one of the new knife supply vendors were to start producing a high quality, properly processed strop, the cost would be immaterial to me, and I'd praise that vendor to the rooftops. So far, I haven't seen one. Instead, they are resorting to making fancy wooden handles, 'trick' multi-sided devices, and using exotic leathers to entice buyers into selecting their products over their competitors.
NOTE: Yes, this is obviously one of my pet peeves, and my current soap box rant...
This is why so many people think leather makes a poor substrate for stropping, and gives leather a bad rap. It's too easy to round off an edge with a soft leather strop if just the slightest bit of over-pressure can curl the leather over it. With a large, fixed-blade knife, that over-pressure can be simply the weight of the blade itself! Unfortunately, so many vendors these days are selling what they call 'strops' without taking the time or effort to properly treat the leather first.
If you properly process a piece of veg tanned leather, the surface will be quite hard, not dent easily with pressure from a fingernail, (or knife blade) and the subcutaneous layers supporting it extremely dense. THIS is what makes a good, high quality strop, and why these high quality strops can last from generation to generation. I have my grandfather's razor strop, passed down from my father. I'll pass it on to my son when I'm done with it.
Technically, you can 'strop' on a cotton T-shirt or 'strop' on water buffalo shank hide, gazelle skin, or kangaroo. To 'strop' (the verb) is to move a blade back and forth with intent to sharpen. 'A strop' (the noun) is the thing you strop on. There are lots of ways to use the word strop. Obviously, anything sold with intent to sharpen like this 'can' be called a strop.
But... there really is a difference. And the biggest difference in the animal skins used is NOT the species. It's the processing. A veg tanned cowhide that has been properly processed will be more effective, even used bare, than improperly processed shell cut of horse hide. Both horse hide and kangaroo hide, if both processed the same way, will perform equally well. They are both grass-fed animals so the silicate quantity in the leather will be about the same for both. But cowhide processed this same way will be just about as good. Not quite equal, but close enough to be counted in the running. The devil is in the details, and in the case of strops, the details are found in the process.
For a flat bevel edge, it is imperative that the surface of the strop NOT flex at all during the stropping process. Even the slightest flexing will begin to round the apex. NOT OPTIMAL! On the other hand, if one's goal is to strop a convex edge, a slightly softer substrate might be preferred.
He should get the same results he'd get with unprocessed horsehide. As long as one's pressure doesn't flex the surface, they should work in equal fashion. But if a fingernail can dent the surface, imagine what a knife blade can do!
Again, not a problem if you want convex edges.
Stitchawl