Strop Expectations

I generally finish all sharpening progressions with a final stropping. Lately I have been using 4µ Diamond Emulsion on leather followed by the 2µ emulsion. This for me brings noticeably better results out of my freshly sharpened edges. I have been very pleased with the results. Just to let you know, I’m using 2º lower stropping angle than the sharpening angle.

The question I’m asking is in your experience do you find any difference or improvement in the feel of the edge sharpness when using more then just a pair of strops. If I follow the 4µ/2µ pair with say the 1µ/0.5µ pair will I see an improved sharper edge or just a more polished edge or both. What’s been your experience?

I’m also interested in this question. I recently acquired two additional sets of strops so that I now have the 14 / 10, 4 / 2, and 1 / 0.5 micron strops. I’ve only used them all on one knife so far (and it was a cheap one). The knife was sharp at the end of the stropping, but not as sharp as it was after the first set alone. I finished it with a micro-bevel and it turned out great. The next time I do a knife that I have some more familiarity with I’ll check sharpness between strops and see how it progresses.

I’ve found a very similar results when dropping 1.5 to 2 deg. with cow hide and no micro bevel.

With multiple strops, while trying for the “show knife” finish, I’ve used a micro bevel before stropping and then back off 2 deg. from the first bevel.

Example: sharpen at 17 deg. micro at 20 deg. then strop at 15 deg.

This allows me to strop a long time before I even start to effect the cutting edge. The trick ??? is to finish stropping when you determine you are at the sharpest. How long? Depends on how big the micro is, what is the angle difference between the micro and the sharpened angle, the compound, the strop material, pressure and several factors I haven’t even probably considered yet. When done long enough, without dulling the edge, you will have a slightly convex and very shiny bevel.(not a true convex but rounded at the shoulder of the micro and the shoulder of the bevel) I’ve used the progression of 4/2/1/.5/.25/.125/.05/.025 all on kangaroo with good results. I could have had the knife just as sharp in 1/10 the time using one set of strops but then it wouldn’t have looked so “pretty”.

One thing that I think would help most people not familiar with stropping is to play with the pressure on the strop. I start out with a lot of pressure on the strop and when it starts to feel sharper, through testing, back off the pressure a little and look for improvement and repeat until satisfied or you think that it’s as sharp as it’s going to get. If the pressure is to heavy for to long the edge is ruined however if the pressure is to light you won’t ruin the edge but you won’t get the desired results either. Find what works for you!

Organic I like the 14/10 strops especially for knives I’ve finished at 600 to 1000 grit diamonds. The paste is aggressive and the 14 leaves an almost burnished look and the 10 side polishes a bit more. They are very fast so check often when you start using them.

I find continued improvement when I use multiple grit strops. An example is when I’m looking to get a knife passing HHT - the finer in grit I go as I strop, the better the knife does w/ the HHT test. It may go from HHT-1 to HHT-5 if I get all the way to .125 CBN on kangaroo.

Clay what amount of pressure do you exert? Is the pressure you use the same for each grit or do you lighten up your pressure as the grit decreases? Are all grits used at the same angle, I’m assuming, 2º less angle than the sharpening angle?

For an edc or a generally/daily use kitchen knife what type of strop progression would you follow? Is it a basic 2 grit, (fine 4µ/extra fine 2µ), like I’m doing or would you still run a whole multi-grit strop progression?

Great questions, great thread! All grits are the same angle and I try to be as light as possible when going for maximum sharpness. For EDCs, I stop at the 4/2. After using the knife a bit, I might decide to strop at the original sharpening angle, sacrificing some sharpness for a little more durability. I know that might seem to contradict what I’ve said previously about lower angles, within the limits of the steel, have better edge retention, but in the specific case of stropping, it can work the other way. The reason is because, at lower angles, the leather will stretch the metal into a tall, narrow peak. The peak is very sharp, but also fragile. If you strop at the sharpening angle or even a degree or two higher, it has the opposite effect in that it creates an apple seed shape instead of the tall, narrow peak.

Thanks for sharing your insights Clay! Also, you really need to update your avatar.

That’s weird. I didn’t realize that it had disappeared!

wow this forum gives me some options. I have been stropping 11 degrees more acute than the stones or film to retain edge strength. But with my straight razor I lose endurance with the edge for A while after sharpening the razor with the “Black Arkansas” stone, now I know why the stropping give me a stronger edge. Thanks Clay

Clay I have never heard anyone say that stropping was anything but destructive to an edge when used at an angle above the sharpened angle but I have to say that after thinking about it there is a certain logic to it.

I’ve shared this before but my starting angles are, 2 deg. less for balsa, 1.5 deg. less for leather and 1 deg. less for kangaroo. Please remember that nothing is set in stone when it comes to stropping, at least from person to person.

 

I have an update: I sharpened my trusty 8" Victorinox chef knife today and used the following progression at 20 degrees per side: 400#, 600#, 800#, 1000#, 1500#, 1.4 micron ceramic, 0.6 micron ceramic, 14 micron diamond paste on cow leather strop, 10 micron diamond paste on cow leather, 4 micron diamond emulsion on cow leather, 2 micron diamond emulsion on cow leather, 1 micron diamond emulsion on cow leather, and 0.5 micron diamond emulsion on cow leather. I stropped at 1.5 degrees lower than my sharpening angle (18.5 degrees) and used medium pressure. The blade got noticeably sharper after the first strop. The increase in sharpness continued with each subsequent strop however the changes were less substantial with each additional grit. The end result was a mirrored edge that whittles hair and easily passes the hanging hair test at HHT 3 level. It is quite possibly the sharpest edge I have ever put on a blade. Conclusion: strops are great!

Organic: I bought the same chef’s knife, just to study it. It has been the top knife tested on America’s Test Kitchen and in Country Cook’s magazine (same people) for at least several years. I took a short video of the knife out-of-the-box (before) and after sharpening on the WEPS, but haven’t posted it on Youtube yet. No doubt it’s a very sharp knife as it comes from the factory. The blade is quite thin, but not as thin as some others and the blade is easily wider than any other knife I’ve owned. The handle is a heavily-textured plastic, which gives it a cheap look, but offers a very nice gripping surface. At $39, it’s a good value. I haven’t used it enough to see how durable the edge is.

I’ve had mine for about 3 years now. I also purchased it based on the glowing America’s Test Kitchen reviews. I have found that the edge retention is okay, but not great. It is absolutely better than the edge retention on my el cheapo Farberware knives with Chinese mystery steel, but not even in the same ballpark as my Kanehiro aogami super gyuto. The Victorinox needs to be stropped probably once a week or so to keep it in top form when used on polycarbonate cutting boards. I imagine it would go quite a bit longer with a proper end grain board like I use with the Kanehiro, but I like to use the poly boards for meat preparation because they can be bleached and put into the dishwasher. While I do find that the knife preforms well enough for anyone’s needs, the gyuto that I have has made me realize what is possible and the Vic. is nowhere near as fun to use. It is a good value and probably just as good as your typical Henkel or Whustof for less than half the price.

I thought I’d post another update. I used the chef knife to cube some chicken breast for the sweet and sour chicken that I made last night and the cutting performance was markedly better than I have previously experienced with the same knife sharpened up to 1500 grit with and then stropped with the 4 / 2 micron strop set. Now that leaves me wondering what kind of performance I can expect if I go through the same progression on my gyuto.

The situation I run into is when I’m going to try to do something to attain better results, such as Organic did with a more involved strop progression, I usually pay more attention and exercise a liitle more care than usual during the entire process because I know I’m looking for improved results. Often by doing just this I have skewed the results with the extra care.

I believe the only way I can tell if the extra stropping really has made the difference is by repeating the same process on a number of knives with an equal attention to detail. As we know with knife sharpening we get out what we put in.

 

I do share your concern. I spent about two hours on the progression which is quite a bit longer than I typically spend on a knife. I also used the 1.4 / 0.6 ceramic stones (also recently acquired) after the 1500 grit diamond rather than going directly to the strops. That could have made a difference as well.

I’ve got nothing to add here except appreciating the knowledge you all are sharing on this thread. I wanted to thank you.

What is the rational of altering the stop angle relative to the sharpening angle? It seems like increasing it would cause a “micro-strop” while decreasing would cause you to be sharpening behind the edge, and not the edge itself.

Cameron, watch this YouTube video made by long-time WE user where he explains some stropping theory. It should help you gain some insight in the need to lower the angle while stropping.

I started with the WE a little over a year ago and shortly there after started playing with the angles while stropping. The conventional theory was back off 2 degs. I do back of 2 degs. with leather and use a heavy pressure on some. Since Clay’s earlier post I have done a couple at the same angle as the sharpened angle and with less pressure and found the same result as I found early on. It refines the blade very quickly and then starts to lose a little when to much pressure is used. By backing off the pressure the results were astonishing. The trade off? It takes a lot more time but you can achieve results that are, well, astonishing to me at least. Now I’m trying to determine if the edges are going to be more durable as well. I would encourage everyone to play with the stropping methods and techniques. I’ve spent more time on stropping than I have on sharpening I think and it seems to me that for every answer I come with, 2 or 3 more questions and variables come into play. The sharpening aspect has certain methods and techniques that pretty much work as expected pretty much every time. Strops…not so much!