Stropping

[Cliff Stamp]

You split the atoms of every hair you come across ....

In regards to discussion on performance of steels, geometry and such yes, I tend to be detailed. On Bladeforums however I don't generally induce semantic debates about detailed grammar issues.

Views or no views, if stropping on paper works, that's more important ...

You would hope that would be the viewpoint of someone who makes their living as a sharpener. Lee discusses this in detail noting the severe resistance of several more productive methods of sharpening as well as tool use/design simply because they were in direct contrast to what was popular/accepted. A lot of people have a large inertia to change but that kind of baggage isn't something you would want to use to indoctrinate someone being introduced into the methodology.

-Cliff

 

[db]

Swaim showed in detail how many of the common "truths" about sharpening, repeated for long times by "experts" were completely false.

What are these completely false common truths, and who are these experts that repeted them for long times?

 

[thombrogan]

You would hope that would be the viewpoint of someone who makes their living as a sharpener.

Not on my wishlist to change Dave. If it were and I were successful, that'd be creepy.

Lee discusses this in detail noting the severe resistance of several more productive methods of sharpening as well as tool use/design simply because they were in direct contrast to what was popular/accepted. A lot of people have a large inertia to change but that kind of baggage isn't something you would want to use to indoctrinate someone being introduced into the methodology.

That doesn't sound like D_R_Sharpening at all. We corrupted him into getting a belt sander and he corrupted his corruptors with sander modifications and the joyful world 600 grit SiC belts (which also r0xx0rs the h0us0rs for prep-polishing jasper before finishing with 3M's 15 micron SiC belt).

 

[db]

In regards to discussion on performance of steels, geometry and such yes, I tend to be detailed. On Bladeforums however I don't generally induce semantic debates about detailed grammar issues.

-Cliff

LOL, if you say so.

 

[cbwx34]

Cliff,

In your last response (to me) you're talking about paper. I was talking about your reference to using the palm of your hand as a strop. That I believe is what you switched from saying it was for stropping to saying it was for cleaning, and gave the examples that you did.

cbw

 

[D_R_Sharpening]

You would hope that would be the viewpoint of someone who makes their living as a sharpener.

-Cliff

Yup, I happen to have stumbled on the old school secrets of sharpening and now I will not change. That's my motto and I'm sticking to it.

Good one - want to try again (self) professor?


--Dave--

 

[D_R_Sharpening]

I think I"ll start a new thread since I've taken this one off topic.

--Dave--

 

[D_R_Sharpening]

........

 

[Cliff Stamp]

What are these completely false common truths, and who are these experts that repeted them for long times?

I have noted many of these in detail on the reference pages I wrote which cites many of Mike posts and I have also showed independent studies which supported Mike's work such as Buck's CATRA work. About 5 years after Mike's work on rec.knives I had a conversation with Wilson and he repeated almost the same things word for word in regards to edge finish and the effect of profile on sharpness and edge retention.

Note in Wilson's recent hemp cutting, if he had started with a higher polish not only would the initial cutting performance be worse (the sharpness would be lower) the cutting ability would decrease faster (the edge retention is less). If the edge profile was thicker than he would also cut less rope before his stopping point (so less edge retention). Yet it is very common to hear the exact opposite of each of these as definate truths.

That I believe is what you switched from saying it was for stropping to saying it was for cleaning, and gave the examples that you did.

I never switched, it is stropping as it is edge trailing, what it does on knives is clean because it isn't abrasive, just like plain leather, or plain paper, or wood. There were frequent claims that leather will act as an abrasive due to silica but this is false on modern cutlery steels, see Verhoeven's work for details where he checked the edge under high magnification before and after.

Of course loaded leather will act as an abrasive just the same as if you loaded paper or wood or anything else, sandpaper of course is just paper loaded with an abrasive. It doesn't take much to realize that instead of buying very fine 0.5 micron made paper you could just use newsprint and a bar of chromium/aluminum oxide.

However Hob has noted that you can see significant distortion cutting even light threads with straight razors so since the edge on these is so much easier to distort it would be reasonable to assume it could be bent back with similar very low force so for the light distortion seen on cutting hair it might be that plain leather, or newsprint, or wood, or your hand, etc. could all act to align the edge on a lightly used straight razor. However again, if used as part of the sharpening process, it would be a cleaning step.

-Cliff

 

[D_R_Sharpening]

Leather (even plain leather) has "draw" to it which will remove microscopic teeth along the edge.

Paper, leather, or whatever is abrasive to some extent. It shall not simply clean but refine a scratch pattern which translates into finer sharper edges.

Why does the barber not call his strop a "cleaner"? Hmmmm...

--Dave--

 

[Cliff Stamp]

Paper, leather, or whatever is abrasive to some extent. It shall not simply clean but refine a scratch pattern which translates into finer sharper edges.

No it doesn't. This has been measured, again see Verhoeven's work. This is an example of one of the common myths still being propogated. There is some abrasion in an absolute sense in pretty much all media but the abrasion of paper or leather on modern cutlery steels is quite low, this is why it would not be efficient to buff out scratches on a blade using a unloaded paper buffing wheel or a plain leather strop. This is why polishing compounds are used and why cutlery steels need much more aggressive ones than the softer metals. Now if there is a significant deformation burr then you can break it off by stropping on leather or paper but that is hardly optimal as it leaves a jagged and broken edge and if anything is misuse of a strop as you can get a much better edge off of a stone with proper technique to minimize the deformation.

-Cliff

 

[cbwx34]

Cliff,

So I just want to see if I understand this correctly. Within a span of about 30 or so posts, you've redefined stropping to mean... any trailing edge motion across a surface, that, at the very least, cleans debris off a knife?

cbw

 

[yuzuha]

Can't say I've ever used newsprint, but I've used typing paper, wood and the posterboard backs of legal pads before... mostly on pocket knives when I've used one to cut something. Partly to clean any gunk off the edge (especially after cutting apples etc. that could cause a bit of corrosion or leave gunk on the blade) and partly with the idea of a makeshift steel, figuring "can't hurt, might help."

Never bothered to actually test the effects of this impromptu "stropping" and I know it doesn't have the effect of a good leather strop (charged with diamond, Linde A or chrome oxide dust) that I've had time to get the feel of, or some very careful, light, edge trailing strokes on a 10k+ waterstone; but it is a comforting ritual anyway.

 

[db]

Quote:

Originally Posted by db
View Post
What are these completely false common truths, and who are these experts that repeted them for long times?
I have noted many of these in detail on the reference pages I wrote which cites many of Mike posts and I have also showed independent studies which supported
Mike's work such as Buck's CATRA work

Um thanks for not answering either question. You think you could not hype your web site and maybe give an answer?

 

[D_R_Sharpening]

No it doesn't. This has been measured, again see Verhoeven's work. This is an example of one of the common myths still being propogated. There is some abrasion in an absolute sense in pretty much all media but the abrasion of paper or leather on modern cutlery steels is quite low, this is why it would not be efficient to buff out scratches on a blade using a unloaded paper buffing wheel or a plain leather strop. This is why polishing compounds are used and why cutlery steels need much more aggressive ones than the softer metals. Now if there is a significant deformation burr then you can break it off by stropping on leather or paper but that is hardly optimal as it leaves a jagged and broken edge and if anything is misuse of a strop as you can get a much better edge off of a stone with proper technique to minimize the deformation.

-Cliff

Cliff,
I don't need to cite the work of another to validate what I speak of. I'm telling you what I know to be the truth.

It's not "a common myth still being propogated", but it is actual fact based on long hours of trial and error.

One of the items that I sharpen a lot of is high end convex ground hair shears. These shears are, when sharpened correctly, almost as sharp as a straight razor and certainly as fragile. They're edges must be "stropped" to the highest level possible and every last bit of burr must be removed through refinement. The window of what works great and what doesn't work at all is extremely small. It's within these parameters that I have come to study the sharpened edge in great detail. I have taken what I have learned in this field, combined with hundreds of hours of hand sharpening high end Japanese cutlery to come to my conclusions. I do not speak from someone else's opinions, and /or writings, I cite my own.

You are dribbling again and it's becoming tiresome to watch. You're wrong whether or not you want to see it.


--Dave--

 

[D_R_Sharpening]

Quote:

Originally Posted by db
View Post
What are these completely false common truths, and who are these experts that repeted them for long times?
I have noted many of these in detail on the reference pages I wrote which cites many of Mike posts and I have also showed independent studies which supported
Mike's work such as Buck's CATRA work

Um thanks for not answering either question. You think you could not hype your web site and maybe give an answer?

He never answers anything directly. I wonder how much bandwidth he has taken up over the years with his constant dribble of BS? It's a big smokescreen if you ask me.


--Dave--

 

[Cliff Stamp]

... and maybe give an answer?

The pages on the website answer it in detail, that is the reason FAQ's exist, so you don't have to type the same thing over and other. In fact very recently I explored one of these myths in numerical detail which was based on the idea Swaim promoted of the influence on geoemtry on cutting lifetime.

I don't need to cite the work of another to validate what I speak of.

You are actually critizing the fact that I am using published facts and data to support my position, that is as absurd as db's comment that I should not site a FAQ.

Doing actual research you have to be both aware of the work others have done and cite it accordingly. This is to show respect for what they have achieved especially if you have learned from them and not simply claim everything you have done as something unique you have origionated. It also shows that you have done the necessary work because before undertading a study of something you should first see what is actually known. This is why papers have a multitude of references cited, both to develop the history and any and all supporting work done by others. If there is work which contends what you say then you have to deal with that as well citing why their methods were flawed or their conclusions are not supported by the data. This is how actual knowledge progresses.

Verhoeven showed the edges under high magnification and thus it is measured fact. I have also measured the sharpness before and after and checked them under low magnification (10-100 X). There is no difference on properly sharpened cutlery aside from a light cleaning. Again, this should be obvious because if the leather/paper had enough abrasive qualities to actually directly reduce the size of the microteeth you could use unloaded leather or cardboard/felt wheels to polish primary scratches out of primary grinds. Yes, if the edge is highly deformed or ragged then you can see a benefit to stropping on unloaded paper as you will break off this debris. However as noted this isn't optimal technique on the stones.

Lee and Verhoeven both showed how edges can be produced to the limit of the grain size of the steel, sub micron, and unloaded stropping won't refine them further. There was a similar study in a wood working magazine a few years back which also showed the same thing using sub-micron diamond abrasives to produce the highest quality finish. There are also a group of guys studying plane blades and have also found that diamond abrasives are needed for optimal sharpness, not only would plain leather do nothing productive, even chromium oxide which is very commonly recommend isn't optimal due to the very high carbide, especially vanadium of those steels. These are guys who both measure the sharpness directly (including a method I developed) and examine the edge under high magnification both before and after extensive use. I have also cited this work on the web pages.

-Cliff