Stropping is King

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I still believe that this forum has nurtured the honing side of SR shaving to the detriment of correct stropping technique. One cannot live without the other but both play at least an equal part in the final outcome.

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That's what I thought, but there are some here who do only honing, at least when traveling. There's a recent thread about it (or part of a thread). In other words, they get down to a very fine hone or pasted strop and touch up when needed. My only comment was it wears out your razor unnecessarily.

There's no right or wrong here. It works for these guys. Just like stropping alone works for others.

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Do you all think that this favour is granted to hones because the act of honing is many faceted but clear to understand. Or is it stropping has too many variables in its practice that can effect the outcome, that people just dont understand that this could be where they might be going wrong when they get razor burn.

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No, I think stropping is so deceptively simple tha it just doesn't receive enough attention. On the other hand there are some that use only strops (pasted strops included). At the same time, it's amazing how often a newbie will mess up his razor on the strop before he ever uses a hone.

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An adequate honing job on a razor can still be made to shave excellently if properly stropped. On the other foot, an excellent hone job can be made useless by poor stropping technique. 50/50 don't you agree?

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No. You could also be a superb stropper and never get your edge to the point of being able to use it because of poor honing technique. I think each of us eventually develops an approach that works for them. The typical approach is to use both.

But apparently, once your razor is shave ready you can keep it that way with a hone only or (a slightly abrasive) strop only.

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Originally Posted by AFDavis11

In my opinion its not heat, but "stickiness". Just like pulling a rope faster to get more force you get more "stropping" force by pulling quicker against the leathers "catch".

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The stickiness or draw is just friction. It's all inseparable. Frictional resistance is related to the force you apply. Friction produces heat. If you strop faster, the heat builds up faster.

It's quite possible that Scott's technique depends on the generation of more abrasion (friction), as I mention above.

Here is what I did last night. I took a razor on its last legs, about the 6th shave and it was pulling. So I stropped it only. I used lots of pressure on linen 20 strokes, then lots of pressure on leather 20 strokes. I strop very very fast btw. I did a total of 60 passes probably. Then I did this series twice and test shaved. . .

the shave was poor, very poor, but then;

I did a series of ten strokes on leather with lighter and lighter pressure until I returned to my usual light stroke on leather. So 10 lighter, then another 10 lighter still, etc. About another 30 strokes total. And sure enough the razor is again shaving like it did day one off the hone.

So based on this I'm up for a little experimenting . . .

I will hypothisize that we hone and use light stropping strokes to maintain the edge, when that fails we hone or perhaps could use aggressive stropping to create an edge that is again realigned (regardless of sharpness).

I'll try some stuff out and post!

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Originally Posted by Joe Lerch

The stickiness or draw is just friction. It's all inseparable. Frictional resistance is related to the force you apply. Friction produces heat. If you strop faster, the heat builds up faster.

It's quite possible that Scott's technique depends on the generation of more abrasion (friction), as I mention above.

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Yes, but if you strop like crazy with enormous pressure and speed the blade doesn't even get warm. So friction I can buy, heat is another matter. I suppose you could believe the tempurature of the edge is rising and effecting the steel, but I'm saying that Im inclined to not believe that heat is the catalyst.

It's only the cutting fin we're talking about here, it's very thin so it wouldn't take much friction to heat it up (because there's just not much mass there). OTOH, it's attached to a giant heat sink, so if the fin heats up it cools back down to ambient by the time you've finished flipping the blade.

I'm sceptical that heat has anything to do with it -- I suspect that speed and pressure are partially fungible -- either way the fin is hitting the leather hard.

One possible explanation for what some members are observing is that the bevel itself isn't stable over time. We tend to think of the business end as being "bevel" + "fin", but really there is a continuum between those two. The boundary area between fin and bevel may be warping over multiple shaves, and light pressure on the strop isn't enough to bring it back to sharp.

Or it's possible that unpasted strops are more abrasive than we've been giving them credit for.

HandAmerican advertise leathers with high silica content. I am not sure whether that is a natural or an artificial "ingredient" of leather. That might account for the abrasive qualities of some leathers.

Silica is also considered to be the abrasive agent of the linen strop:

"And he mentioned something about the superior abrasive quality of linen over cotton in the manufacture of canvas strops. This may help clarify the intended purpose of using the linen when stropping."

The latter quote I took from the first post of the thread Illinois Razor Strop Company started by Scott (Honedright).

That's interesting about the silica content - my edges have been lasting noticeably longer since I switched to the hand american strop.

This is a great thread. I'm particularly interested in what Alan finds out with his experimentation.

I've been doing some more experimenting of my own. (My hair and my wife's hair works great for the HHT, so I have a pretty good benchmark to go against.)

This morning I tested my razor before stropping. It broke hairs, but didn't cut them cleanly. After 30 laps on the linen, it was back to popping hairs. I'm amazed at how well the linen works; Kees mentioned an abrasive in the linen, and I wouldn't be surprised. I used to think it was just cloth.

About 50 strokes with medium-easing-to-light pressure on the leather put an even finer edge on the razor. Cut cleanly through hanging hairs--wow. I'm on my third shave since the pasted strops and there's no noticeable dropoff in sharpness.

I'm wondering if my edge isn't a little weak. I only go up to .5 microns on my pasted strop, but I have a coarse beard. I'm still working on my shaving technique, so I'm not sure what to expect.

Keep the interesting info coming,
Josh

I'm starting a new thread "Testing the limits of a strop"

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Originally Posted by AFDavis11

Here is what I did last night. I took a razor on its last legs, about the 6th shave and it was pulling. So I stropped it only. I used lots of pressure on linen 20 strokes, then lots of pressure on leather 20 strokes. I strop very very fast btw. I did a total of 60 passes probably. Then I did this series twice and test shaved. . .

the shave was poor, very poor, but then;

I did a series of ten strokes on leather with lighter and lighter pressure until I returned to my usual light stroke on leather. So 10 lighter, then another 10 lighter still, etc. About another 30 strokes total. And sure enough the razor is again shaving like it did day one off the hone.

So based on this I'm up for a little experimenting . . .

I will hypothisize that we hone and use light stropping strokes to maintain the edge, when that fails we hone or perhaps could use aggressive stropping to create an edge that is again realigned (regardless of sharpness).

I'll try some stuff out and post!

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I can't explain this other than this was a case where you need to realign the fin and your normal stropping did it. Heavy stropping might have just moved the fin too far (back and forth), giving you nothing.

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Originally Posted by AFDavis11

Im inclined to not believe that heat is the catalyst.

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I agree. You can buff a blade for a long time on a machine before you feel the temperature increase. It's not likely you could do it manually.

2¢ here. Heat stressing of metal occurs simply from the friction of the iron atoms against one another by bending. That has an effect.

X

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Originally Posted by mparker762

Or it's possible that unpasted strops are more abrasive than we've been giving them credit for.

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I think that's the case with the strop Scott is using. He's not doing enough reps for a clean leather strop to generate the necessary abrasion, but he does have to remove the same material that a .5 micron strop would in 20 reps. He has 400 reps to do it. If he had 4000, maybe a plain leather strop would work.

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Originally Posted by joshearl

This morning I tested my razor before stropping. It broke hairs, but didn't cut them cleanly. After 30 laps on the linen, it was back to popping hairs. I'm amazed at how well the linen works; Kees mentioned an abrasive in the linen, and I wouldn't be surprised. I used to think it was just cloth.

About 50 strokes with medium-easing-to-light pressure on the leather put an even finer edge on the razor. Cut cleanly through hanging hairs--wow. I'm on my third shave since the pasted strops and there's no noticeable dropoff in sharpness.

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The idea is not to use anything but the linnen and leather of the strop and see if you reach a point where just stropping will not restore the edge.

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Originally Posted by xman

2¢ here. Heat stressing of metal occurs simply from the friction of the iron atoms against one another by bending. That has an effect.

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True, but it won't elevate tempperature to the point you can sense it without instruments.

You guys don't think he is just realigning the edge with stropping? Or put another way, realigning it better?

Because the science and theory say "it won't work" it doesn't explain why it does. :) I can't be persueded that stropping doesn't remove enuough material to sharpen an edge and polish at the same time.
Granted it will take longer, but then I'd expect it to. After finish honing with say a 8-12k hone, you could only go to something finer for the finishing steps with a strop. I base this on the leather strop wheels i use on my lathe for sharpening wood turning chisels. After grinding to the correct bevel and sharpness, I then put them across my leather hone mop. This you can see metal being removed all be it, slower. I will concede that heat is produced but this is not what removes metal, it's the abrasive qualities of the leather. I must point out that the speed is 300rpm or lower depending on the weight/mass of the tool being sharpened so that heat is not going to draw the temper too fast to correct.
So my point is that a plain leather strop does sharpen a razor all be it slow and finely. To use pasted strops just speeds up procees like going from 4k to 8k on a hone.

PuFF

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Originally Posted by AFDavis11

You guys don't think he is just realigning the edge with stropping? Or put another way, realigning it better?

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I do. We're talking about the thinnest steel known to man (feathers and some atomic science weirdness aside). I believe it responds to everything we do with it. If shaving against my puny whiskers puts the edge out of joint, I'm sure stropping can have a profound effect if taken to extremes and perhaps even not that far.

X

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Originally Posted by AFDavis11

You guys don't think he is just realigning the edge with stropping? Or put another way, realigning it better?

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I'm skeptical. Linen and leather are both abrasive to some degree, linen is probably the more abrasive of the two.

somewhat off-topic but possibly relevant: I've got a few muzzleloaders, and muzzleloading rifles use a lead ball wrapped in cloth and shoved down the barrel. After a few cycles of the cloth-wrapped ball going down and up the barrel the inside of the barrel gets noticeably polished - machining marks are gone, the corners of the lands lose their sharpness, etc. And muzzleloader patches are made of pillow ticking which is a lot softer than linen.

Now rifle barrels aren't as hard as a razor blade, but I can easily believe that an unpasted linen strop is some reasonable percentage as abrasive as a .5 chrome oxide paddle - if it's even 2% as abrasive then giving the razor 80 firm laps on it may be equivalent to as much as 10 light laps on CrOx, which will make a substantial difference in the quality of the edge.

As for why the razor needs light stropping after the firm regimen, the newly-refreshed fin will be left bent over from the hard stropping (this sounds like a tenacious d song) and still needs to be aligned.

One theory I've heard put forward by someone very experienced in metallurgy is that the oxidation and removal of the oxidation is what really causes the "fin regeneration". Fishhooks and files are two steel tools that are acid sharpened. Essentially, they're sharpened by chemically oxidizing the steel. When the oxidation is removed, a fresh layer of steel that is "chemically sharpened" is revealed.

I can neither confirm nor deny this theory, but thought I'd mention it.

As best I can tell, stropping simply polishes and refines the edge by abrasion.

[quote=PuFFaH;74586]

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Because the science and theory say "it won't work" it doesn't explain why it does.

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Come on it's not rocket science. It has to follow the basic rules of physics, assuming you're reality based.

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I can't be persueded that stropping doesn't remove enuough material to sharpen an edge and polish at the same time. Granted it will take longer, but then I'd expect it to.

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Normal leather stropping does not. Prof Verhoeven found that in his sharpening treatise. Science doesn't say it won't work. It says everything is abrasive to some extent. After all rocks are worn away by water. And you're right it would just take longer. A lot longer. Forty reps or even 80 reps on plain leather won't do it. Ten times that many might. That's based on the fact that, on the average, refreshing with a .5 strop is required after after 10 shaves, and it typically involves 20 reps. In other words after 10 shaves you need to remove as much material as 20 reps on a .5 micron strop.

I'm not saying a strop can't do it, but it would have to be abrasive enough to remove that much material. If you'e doing 40 reps each time, you would have to be abrasive enough to remove the material in 10 days (400 reps, 800 reps if you do 80 at a time). The number of reps is kind of typical, and the fact that abrasive honing or stropping is required after ten days tells you that the typical leather stop doesn't cut it, as confirmed by the profs research. Now if you did ten times that number of reps or used a machine, it might.

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After finish honing with say a 8-12k hone, you could only go to something finer for the finishing steps with a strop. I base this on the leather strop wheels i use on my lathe for sharpening wood turning chisels. After grinding to the correct bevel and sharpness, I then put them across my leather hone mop. This you can see metal being removed all be it, slower.

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This just goes a long with what I say. How many reps would you have to do by hand to get the same result?

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I will concede that heat is produced but this is not what removes metal, it's the abrasive qualities of the leather.

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Right, but the heat tells you it's being abraded much faster than by hand, where there's no heat.

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I must point out that the speed is 300rpm

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To get a feel for how many manual reps this would be, multiply the belt speed by the time you hold the blade in place for one side. Then divide by the length of your strop. This is a very conservative estimate of the equivalent number of manual reps.

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So my point is that a plain leather strop does sharpen a razor all be it slow and finely. To use pasted strops just speeds up procees like going from 4k to 8k on a hone.

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I agree, but to get the effect you're looking for with the number of reps being used, you need something more abrasive than plain leather. The abrasive quality would probably have to be the equivalent of a 500K grit, or .05 micron. I say Scott must have that on his strop. That's the only physical explanation of why he would never have to refresh his razor. The rest of us don't have the abrasive and need to refresh or do occasional honing.

Scott's approach is just an extension of refreshing. When we refresh we do a little material removal every ten days, as compared to doing a lot of material removal every few months. Scott removes a minute amout of material with every stropping, instead of removing a little every ten days.

[quote=mparker762;74645]

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I can easily believe that an unpasted linen strop is some reasonable percentage as abrasive as a .5 chrome oxide paddle - if it's even 2% as abrasive then giving the razor 80 firm laps on it may be equivalent to as much as 10 light laps on CrOx, which will make a substantial difference in the quality of the edge.

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I estimate it would have to be at least 10% to do it with 800 reps (80 per day for 10 days).

Well, most guys do their daily stropping with very little pressure, but these experiments seem to involve a lot of pressure; so 80 laps with a lot of pressure might equal 2-3 laps on CrOx with a lot of pressure. But most of us don't use pressure on the CrOx paddle, so maybe it's equivalent to more light laps?

I'm just guessing here as to what might be providing the sharpening affect these guys are seeing. It could also be accumulated grit on the leather strops from stropping right after honing or paddling that is providing some additional abrasive affect.

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Originally Posted by PapaBull

One theory I've heard put forward by someone very experienced in metallurgy is that the oxidation and removal of the oxidation is what really causes the "fin regeneration". Fishhooks and files are two steel tools that are acid sharpened. Essentially, they're sharpened by chemically oxidizing the steel. When the oxidation is removed, a fresh layer of steel that is "chemically sharpened" is revealed.

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It's plausible, but it just explains why material would need to be removed occasionally. I think we all agree on that.

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As best I can tell, stropping simply polishes and refines the edge by abrasion.

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Sharpening experiments done by Prof Verhoeven show that normal leather stropping after honing doesn't remove enough material to improve sharpness. I do a few reps (15-20), because I find the small amount of polishing adds smoothness.

It's generally accepted that what stropping does is to realign the fin. It's made up of micro-teeth, which get bent in all directions by shaving. Within 2 days they come back most of the way, but not all the way. Stropping just pushes them the rest of the way (stands them up), making the edge effectively thinner (sharper). After about 10 shaves, stropping no longer does it. It may be because of mico-oxidation. Refreshing may remove that oxidation, stroring the sharpness of the teeth.

[quote=mparker762;74757]

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I'm just guessing here as to what might be providing the sharpening affect these guys are seeing. It could also be accumulated grit on the leather strops from stropping right after honing or paddling that is providing some additional abrasive affect.

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He said he put urethane on the strop and then roughed it up with sandpaper. That could be it.

The accumulated grit wouldn't affect the leather ecause he uses linnen first. If it left enough on the linnen, why wouldn't the rest of us get the same result?

What I'm beginning to think is that we have a third form of razor maintenance: leather stropping and periodic honing, leather stropping and frequent refreshing; and just leather stropping with a slightly abrasive strop. I estimate that the third approach could be done with something like a .05 to .025 micron abrasive.

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Originally Posted by Joe Lerch

I say Scott must have that on his strop. That's the only physical explanation of why he would never have to refresh his razor. The rest of us don't have the abrasive and need to refresh or do occasional honing.

Scott's approach is just an extension of refreshing. When we refresh we do a little material removal every ten days, as compared to doing a lot of material removal every few months. Scott removes a minute amout of material with every stropping, instead of removing a little every ten days.

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Joe, you say there is some type of abrassive on my strop, but where did it come from?? I certainly haven't applied any paste or abrassive in the ten years I've been using it. And I've cleaned and dressed this strop many times over the years. It would seem that any paste that could have ever been on the strop would have been removed long ago or reduced to an ineffective amount.

Or, are you suggesting that horse hide cordovan strops are more abrassive than cowhide? That could be so, but I don't know.

Also, I do about 20-30 round trips on both linen and leather before each shave. Isn't this the standard number for most users?

It would be interesting to hear from others who use the Dubl-Duck strops.

Scott

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Originally Posted by honedright

Or, are you suggesting that horse hide cordovan strops are more abrassive than cowhide? That could be so, but I don't know.

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Or a different tanning method. I've noticed that my edges last longer since I switched to a handamerican strop, and they supposedly use leather that is tanned with a special tanning method that leaves silicates in the leather (or more silicates).

[quote=honedright;74761]

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Or, are you suggesting that horse hide cordovan strops are more abrassive than cowhide? That could be so, but I don't know.

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I don't know. I'm just saying the slight abrasive has to be there. You mentioned putting on some uretahne and sanding it. Maybe that's enough. The abrasiveness required for 40 reps would probably be finer than a .025 micron (notice the decimal point) abrasive.

[QUOTE] Also, I do about 20-30 round trips on both linen and leather before each shave. Isn't this the standard number for most users?/QUOTE]We had an experiment here that showed more than 60 made no difference (in terms of stropping only), and 45 seemed to be the sweet spot.

It would be interesting to hear who maintains their razor with stropping only for six months or more and what strops they use and how they're set up.

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Originally Posted by honedright

Joe, you say there is some type of abrassive on my strop, but where did it come from?? I certainly haven't applied any paste or abrassive in the ten years I've been using it. And I've cleaned and dressed this strop many times over the years. It would seem that any paste that could have ever been on the strop would have been removed long ago or reduced to an ineffective amount.

Or, are you suggesting that horse hide cordovan strops are more abrassive than cowhide? That could be so, but I don't know.

Also, I do about 20-30 round trips on both linen and leather before each shave. Isn't this the standard number for most users?

It would be interesting to hear from others who use the Dubl-Duck strops.

Scott

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Scott, what do you dress your strop with? THe dressing might contain some abrasive ingredient or a chemical that reacts with the leather and produces an abrasive surface on the leather.

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Originally Posted by Joe Lerch

I don't know. I'm just saying the slight abrasive has to be there. You mentioned putting on some uretahne and sanding it. Maybe that's enough. The abrasiveness required for 40 reps would probably be finer than a .025 micron (notice the decimal point) abrasive.

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Regarding the urethane (highlighted quote above), you're confusing strops. There is no urethane on my daily strop. My daily strop is the Dubl-Duck - no urethane, no abrassive pastes, just skill. :D

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Originally Posted by Joe Lerch

Also, I do about 20-30 round trips on both linen and leather before each shave. Isn't this the standard number for most users?/QUOTE]We had an experiment here that showed more than 60 made no difference (in terms of stropping only), and 45 seemed to be the sweet spot.

It would be interesting to hear who maintains their razor with stropping only for six months or more and what strops they use and how they're set up.

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You've already heard from one person (yours truly) "who maintains their razor with stropping only for six months or more and what strops they use and how they're set up."

Since my bringing this topic up, it seems that the above is a new concept for many. Not enough time has passed for most to put in the time and practice required to achieve the results that I've had. I think very soon though, you will start to hear from other SR users who are getting better shaves and going longer between honings now that they know it is possible.

Scott

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Originally Posted by Kees

Scott, what do you dress your strop with? THe dressing might contain some abrasive ingredient or a chemical that reacts with the leather and produces an abrasive surface on the leather.

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I use Fromm strop dressing.

Scott

I do not know Fromm strop dressing, it would interesting to know what it exactly contains, it might increase the abrasiveness of your strop leather.

I also thought I would mention this: I haven't always had such great success with my Dubl-Duck strop. When I first started using it 10 years ago, I actually thought it was junk since it didn't seem to do such a good job.

It was only after much practice, trial and error that I mastered using it.

For a moment I was worried that maybe it was only the strop that was responsible for my results. But then I remembered the above experience and firmly believe that it's not just the strop. You still have to know how to strop. A good quality strop doesn't hurt though.

Scott

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Originally Posted by Kees

I do not know Fromm strop dressing, it would interesting to know what it exactly contains, it might increase the abrasiveness of your strop leather.

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As far as I know, it contains no abrassive. It's just a cream style conditioner/dressing.

Scott

Has anyone ever seen a microscope image of an edge that has only ever been stropped? Joe, has Prof Verhoeven in his book got any pictures or done a test on a razor that has only been stropped after the first initial hone? If so was it done for a good period of time?

I would appreciate a heads up on where I can get this scientific treatise on sharpening by Prof Verhoeven.


PuFF

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Originally Posted by PuFFaH

Has anyone ever seen a microscope image of an edge that has only ever been stropped? Joe, has Prof Verhoeven in his book got any pictures or done a test on a razor that has only been stropped after the first initial hone? If so was it done for a good period of time?

I would appreciate a heads up on where I can get this scientific treatise on sharpening by Prof Verhoeven.


PuFF

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Verhoeven's treatise is on sharpening. Only small parts refer to razors or str8 or anything that sharp. But the microphotographs and the results are quite interesting.

He does not try long term stropping only, and he only tried normal leather stropping after honing, finding it had no sharpening effect. I admit it doesn't show that long term stropping couldn't sharpen.

But again, please note that the material removal would have to be enough after 10 shaves. That's the typical time after which refreshing is necessary. A typical way of dealing with it is 20 reps on a .5 strop. Scott does 40 reps per shave, so 400 reps would have to remove as much material as 20 reps with .5 micron paste. I admit that 20 reps or whatever Verhoeven did would not have a perceptible effect if the abrasive were as fine as I describe.

I don't know if the abrasive quality of a plain strop has ever been analyzed, but I'm guessing it's a lot less than what I described, or more people would have noticed this effect.

I think Verhoeven's paper is in our files. If not, do an online search and you'll find it. He doesn't have a very common name.

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Originally Posted by honedright

Joe, you say there is some type of abrassive on my strop, but where did it come from??

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The only thing I can tell you is that there must be. Just like I know there must be gravity if I'm not floating around. Even if you were/are the Michelangelo of stropping, you couldn't remove material without some abrading.

BTW, I use the Fromm cream too. It provides an abrasive quality in that it makes the leather draw more. That means it has more friction (as compared to a strop where the blade slides freely).

Robert says he heard that the reason you need occasional abrasion is to remove micro-oxidation. It's as good an answer as any. But it could also be minute wearing of the fin. One way you could rule out wearing is if the razor needed refreshing even if it wasn't used (you would get the oxidation regardless). I have some razors I may not use for weeks at a time. I've never noticed that they need refreshing after a single use and just sitting around.

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Originally Posted by honedright

Since my bringing this topic up, it seems that the above is a new concept for many. Not enough time has passed for most to put in the time and practice required to achieve the results that I've had. I think very soon though, you will start to hear from other SR users who are getting better shaves and going longer between honings now that they know it is possible.

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It's a new concept because we've never noticed this before, and it's not like we're refreshing our blades every few weeks just for the fun of it (ok, maybe some of us). So why haven't we noticed our blades staying sharp month after month? Looking at your video and reading your descriptions I can't see where you're doing anything that I'm not already doing, which leads me to believe that there's something else responsible, something that you're not aware that's different about your technique or equipment.

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Originally Posted by Joe Lerch

The only thing I can tell you is that there must be. Just like I know there must be gravity if I'm not floating around. Even if you were/are the Michelangelo of stropping, you couldn't remove material without some abrading.

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Well, gravity you can prove, but unless there is some metal residue on the strop, there is no metal removal. The strop simply straighten the edge that is being bent by the hair, just like the scythe man straighten the tool's edge back to shape by hammering it with a hammer.

Nenad

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Originally Posted by superfly

Well, gravity you can prove, but unless there is some metal residue on the strop, there is no metal removal. The strop simply straighten the edge that is being bent by the hair, just like the scythe man straighten the tool's edge back to shape by hammering it with a hammer.

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I don't know if it's metal residue, but my old Bismark strop's linen side had a definite gray hue by the time I got rid of it. And my handamerican strop is getting darker on the side I'm using as well.