Stropping Question

[Shmohawk]

I try to maintain sharpness on my knives by stropping before they get too dull.
The next time they need sharpening I'm gonna give the Vivi Edge a go.

But in the meantime my question for the extremely knowledgeable folks here is this.
I have been using good old fashioned green compound and it seems to work fine for me. I know there are there diamond pastes, juices etc..
Is there any reason for me to switch to one of those for just maintenance? I'm not looking to polish my edges.
Does steel type matter?
I have H1, S30v, 20cv, Cruwear, Spy27, S90v

Thanks!!

[Harkwit]

Steels with a higher vanadium/tungsten/moly/niobium/etc. content (basically anything that isn't chromium carbide) will respond better to diamond pastes by sheer virtue of the hardness of the abrasive medium.

Steels like H1, Spy27, and to a lesser extent Cruwear should perform just fine on green compound, but you'll get better 'results' with diamond compound on your S30V/S90V/20cvs.

[Scandi Grind]

I'm less knowledgable than some, but if green compound works for you, then I wouldn't be too concerned about it. I'm not sure if certain steels might benefit from diamond compound, but even a unloaded strop can help maintain an edge, so I think it is a matter of aggression. Unloaded can "straighten" so to speak, but a diamond loaded strop can actually remove material on a micro level, or in other words polish the edge.

If you had a hankering to try diamond compound, it could be worth a shot to see if you might like it. It really helps to be able to see the results under magnification if you want to understand what is actually happening to the edge. I use a handheld microscope that has zoom between 60x - 120x and it cost about $13. Very handy.

Bear in mind however, that if you are trying one of Vivi's coarse edges, that stropping undoes a coarse edge by flattening out the toothyness. So strops aren't good if you want to keep a toothy edge.

[Shmohawk]

I'm less knowledgable than some, but if green compound works for you, then I wouldn't be too concerned about it. I'm not sure if certain steels might benefit from diamond compound, but even a unloaded strop can help maintain an edge, so I think it is a matter of aggression. Unloaded can "straighten" so to speak, but a diamond loaded strop can actually remove material on a micro level, or in other words polish the edge.

If you had a hankering to try diamond compound, it could be worth a shot to see if you might like it. It really helps to be able to see the results under magnification if you want to understand what is actually happening to the edge. I use a handheld microscope that has zoom between 60x - 120x and it cost about $13. Very handy.

Bear in mind however, that if you are trying one of Vivi's coarse edges, that stropping undoes a coarse edge by flattening out the toothyness. So strops aren't good if you want to keep a toothy edge.

I actually picked up one of those digital handheld microscopes recently but haven't really had time to put it to use yet.

My knowledge and experience is quite limited so I don't have much frame of reference but I find that when I go straight to a green compound strop on an edge that has been used plenty but is still decently sharp, it certainly feels quite toothy and sticky to me.

I'm assuming that on a coarse Vivi edge that would not be the case, like you said. But it seems that one of the benefits of the coarse edge is that it's easy enough to maintain in any case.

[Scandi Grind]

Depending on what you want, stropping a coarse edge doesn't hurt. If your coarse edge was sharp to begin with, then stropping it will not make it less sharp, it will just gradually reduce the aggression of the edge over multiple rounds of stropping. Less aggression means better push cut, worse saw cut. Your preferred level of tooth will be a matter of trial and error over multiple resharpenings.

To maintain maximum toothiness, you would want to simply touch up your edge on a coarse stone when it needs it, but coarse edges do tend to keep their cutting ability for longer than smooth edges, so you may not have to touch up as often.

One thing I've found is that trying things out for yourself then testing the results for your use case is really the best way to maximize your performance, so if you find something you like, don't be afraid to use it. I tried coarse edges on my current EDC, thought it would be great, but found it didn't have enough edge on it's very short tanto blade to saw with, so I went with a smooth edge and have found it much more satisfactory for that knife. But for my current kitchen knives, coarse edges have totally changed how well they perform for the better.

[Scandi Grind]

Accidental re-post.

[Takuan]

For anything with serious carbides in it, I use DMT 1-micron diamond paste on my strop. For carbon steels or softer stainless (e.g., VG-10), I just go with the green chromium oxide stropping paste. I made a two-sided strop from a piece of scrap wood (in my basement) and a bag of scrap leather (which I bought at an art supply store for about $5). I just Gorilla glued the leather to either side of the strop and the cut off the excess. It works perfectly.

[ZrowsN1s]

A progression of 5/3/1 micron cbn or diamond paste will quickly bring most edges back to scary sharp as long as there's no edge damage.

I have a green paste strop too, they all work fine, it's just a question of efficiency.

[Manifestgtr]

If you’re happy with the results, that’s all that matters…

That being said, my sharpening results were completely overhauled when I got my first diamond compounds in. It doesn’t have to be anything crazy…many times, I go no lower than 8 microns. But those 8 microns are 8 aggressive, hair splitting microns that do wonders for my edge health/longevity. On top of that, it works just as well for 1095 as it does for K390.

Again, if green compound works for you and you’re happy with the performance, that’s the only consideration…but as far as my sharpening goes, I haven’t looked back since I discovered diamond compound.

[WyoJon]

I bought a product over ten years ago from a wood working supply company. Called herbs yellow stone. I have razor strops pasted with chrome oxide and iron oxide. This cuts faster than chrome and leaves a finish finer than iron. No idea what is in it, but its peachy color. Put some neats foot oil on the end of it, let it sit a few minutes, then rub it into the rough side of a leather strop. Thats how ive used it. Also rubbed it into cardboard from cereal box and cut it into strips pocket stone sized. That works well too. https://www.woodworkingshop.com/product ... gL-tfD_BwE

[vandelay]

I find strops with non-diamond compound works even on steels like k390.

Science of sharp had an article on stropping. I don't remember what type of steel it was using but it definitely wasn't a super high carbide steel like K390. Stropping with paste wore away a small amount of metal and cleaned up the edge nicely. I'm not sure how much real-world wear that translates to, but in my experience, strops extend the life of an edge by a good amount on steels like 1095.

I'd be interested to know what's going on at a microscopic level when you strop k390. Without diamond compound, would you just be exposing more of the carbides and making a more aggressive edge? Are diamonds able to cleanly cut through the carbides at the edge? K390 lasts so long that it's difficult to test sharpening methods.

[Wandering_About]

I find that stropping with diamond compound works faster on all steels, and one of the keys to making a strop work is to minimize passes. I think the diamond compound refines the apex faster and removes any microburring faster than traditional compounds, and I use it on all steels now.

I use 1 micron diamond on hard, smooth leather. Very light pressure to try to avoid round the apex as much as possible.

If you want to keep things very toothy, you can experiment with larger micron sizes of diamond, but I don't usually use very low grit edges so 1 micron has worked well for me (I usually finish edges on a 1000 grit stone).

[vandelay]

The science of sharp guy tested how much excess stropping affects edge geometry and didn't find much of an effect.

Abrasive stropping rapidly micro-convexes the apex. Additional stropping, up to many hundreds of strokes does not substantially increase the micro-convexity.

Bevel convexity, as distinct from micro-convexity, is not apparent in sub-micron abrasive stropping, but does occur with larger abrasive particles. The quantity of metal that must be removed to convex the entire bevel will result in blackening of the strop, something generally not observed with sub-micron abrasive strops.

The apex geometry is determined primarily by the strop material rather than the abrasive size.

https://scienceofsharp.com/2015/03/31/t ... op-part-3/

Outside of straight razors, I've found that the only things that really affect the outcome of stropping are abrasive and backing choice.

[Shmohawk]

I find strops with non-diamond compound works even on steels like k390.

Science of sharp had an article on stropping. I don't remember what type of steel it was using but it definitely wasn't a super high carbide steel like K390. Stropping with paste wore away a small amount of metal and cleaned up the edge nicely. I'm not sure how much real-world wear that translates to, but in my experience, strops extend the life of an edge by a good amount on steels like 1095.

I'd be interested to know what's going on at a microscopic level when you strop k390. Without diamond compound, would you just be exposing more of the carbides and making a more aggressive edge? Are diamonds able to cleanly cut through the carbides at the edge? K390 lasts so long that it's difficult to test sharpening methods.

I'm not very knowledgeable on the science but I have wondered about this as well

[Bemo]

IIRC from the Science of Sharp articles on the topic, using something like chrome oxide loaded strop will remove the matrix of steel that holds the carbides, leaving carbides more exposed. But honestly read the articles, they're very much worth the time.

[vandelay]

IIRC from the Science of Sharp articles on the topic, using something like chrome oxide loaded strop will remove the matrix of steel that holds the carbides, leaving carbides more exposed. But honestly read the articles, they're very much worth the time.

This is the only image I've found in the articles where it looks like the surrounding matrix was removed.

the knife was micro-bevelled using a translucent Arkansas stone. This type of stone generally removes steel by adhesive wear and its silicon oxide composition is much softer than the vanadium carbides in the K390 steel.

[Bemo]

Thanks Vandelay, that's the one I remember. That's why going to the source is important; memory is fallible and I'm happy to be corrected. Awesome picture. Didn't know there was such a thing as adhesive wear until I read that.

[FK]

I bought a product over ten years ago from a wood working supply company. Called herbs yellow stone. I have razor strops pasted with chrome oxide and iron oxide. This cuts faster than chrome and leaves a finish finer than iron. No idea what is in it, but its peachy color. Put some neats foot oil on the end of it, let it sit a few minutes, then rub it into the rough side of a leather strop. Thats how ive used it. Also rubbed it into cardboard from cereal box and cut it into strips pocket stone sized. That works well too. https://www.woodworkingshop.com/product ... gL-tfD_BwE

For many years I visited with Herb Dunkle several times a year at wood carving shows. His Yellowstone compound is Chromium Oxide with a peach colored dye that was made by Norton years ago. His son is still selling the original compound. Works great on high carbon steel and alloys that do not require diamond strop compounds.

[JD Spydo]

There is another vendor that I've found to be quite resourceful for those diamond pastes and other stropping compounds. It is a woodworker's site called www.japanwoodworker.com. And the quality of the items I've gotten there have all been good. There is one more I remember getting stuff from called "Lee Valley". I haven't dealt with them in a while but they seemed to be a really good resource as well.

There are sure a lot of options with stropping now a days. There is one more vendor I used to get stuff from that were really good known as "Garrett Wade">> they were also mainly a woodworker's supply outfit as well. Interesting thread to be sure.

[FK]

I find that stropping with diamond compound works faster on all steels, and one of the keys to making a strop work is to minimize passes. I think the diamond compound refines the apex faster and removes any microburring faster than traditional compounds, and I use it on all steels now.

I use 1 micron diamond on hard, smooth leather. Very light pressure to try to avoid round the apex as much as possible.

If you want to keep things very toothy, you can experiment with larger micron sizes of diamond, but I don't usually use very low grit edges so 1 micron has worked well for me (I usually finish edges on a 1000 grit stone).

Agree 100% on micro burrs, diamonds quickly remove the tiny burred rolled edge that give a rather weak life to a freshly sharpened edge. This can easily be observed with the relatively inexpensive digital microscope connected to a PC.
I like 3 micron diamonds on a thin hard leather strop. The initial edge with coarse stone or diamond plate,,,,, one early proponent was Wayne Goddard many years ago,,,, and a light touch on strop will give an aggressive slicing edge that is quickly restored on the strop.

Regards,
FK