Seeking advice on stropping.

[JKerr]

Hello,

So I snagged a double sided strop the other day (this one: https://www.chefs-edge.com.au/collections/strops/products/porter-dual-sided-leather-strop-large ). I haven't used it yet but I'd be keen to get some input from those who use them and the how-why-whens of it. Seems a lot of people use them unloaded purely to deburr but there's obviously the world of compounds as well. With so many to choose from at hugely varying price points, what's the difference and for kitchen knives is there a sweet spot? I seen Jende have some diamond pastes that go to 600K which seems beyond excessive unless you plan to give that bristly pork belly a very clean shave before cooking it.

No advice given is too basic, I've never used one so anything is appreciated. Angles, after every stone or only after finishing stone, how much paste to apply etc etc

Generally my work knives after simple carbons. Misono EU, Sugimoto HM, Hitohira SK (forget the line) and a few stainless but nothing super hard, probably around the 60HRC mark. I use King deluxe stones (basic I know, but I like the feel of them) and sometimes finish on a kitayama depending on the knife.

Thanks in advance!

Cheers,
Josh

 

[azn_knives_4l]

I was a fan for both edge finishing and maintenance but have since moved away. Ghosting paper is cool and all but gives up some useful bite. Removing excess convexity is also a pain in the ass.

 

[aporigine]

I have 1-micron CBN on one side and 1/4-micron diamond on the other of a two-sided paddle strop. I use it primarily for maintaining sashimi single-bevels and checking if I need to go to the stones yet on some of my white steel knives.

My two learned things are: the leather substrate has considerable give. Try using a shallower angle than on a stone. This slows rounding the edge into a shape that is wicked sharp but not durable.

The other: if half a dozen passes on the strop do not satisfy, it’s time to go to the stones and reestablish a new clean edge bevel.

Strops are not magic. But for extending the interval between trips to the stones, I have found them to be of value.

 

[Matt Jacobs]

I use a diamond spray on one side of mine. I do a couple passes to deburr probably out of habit anytime I'm done sharpening. Other than that I do notice some benefit on aebl or other easy to sharpen steels but like others here have said it's pretty short-lived and I don't think it replaces sharpening. I really don't notice a difference on the higher edge retention steals. If I do a bunch, I can remove some shiny spots and possibly make paper towel cutting easier. But when you really dig in, you are losing toothiness in my opinion and it doesn't translate from paper towel to tomato skin. Stropping and testing on paper or arm hair. Fantastic stropping and testing on tomato and pepper. I don't see the benefit. Try some different compounds out and let us know what you think

 

[HumbleHomeCook]

Strops are controversial and some people I really respect don't like them. I think they're fine, especially for newer sharpeners or those who are fine with casual engagement.

I like to use compound on the suede (rough) side and leave the smooth side bare. I prefer paste to emulsions as they can dry out the leather quicker. Many of the pastes, often seen in syringes, are garbage. Not all for sure, but a lot. This is really a case of getting what you pay for. A little more invested here gets you a more consistent abrasive size, higher volume of abrasive and better mediums. Sprays are okay but I don't do diamond compounds. I prefer diamond lapping film on a hard backer for that sort of thing.

My preferred compound is this one:

https://bernalcutlery.com/products/...32184&pr_ref_pid=8070197772509&pr_seq=uniform

You don't need to apply a ton. You can even start with a zig zag pattern down the strop to start if you want. Easier to add than remove. You just don't want it thick and flaky. Putting it on the suede side will help with deburring as the fingers of leather can help wrap around the edge.

The smooth side, for me, is purely for a polish and I don't use it very often.

I recommend using your sharpening angle or slightly lower. If in doubt, always go lower until you get a feel for things. Just helps prevent rounding your apex that you've just created on the stones. Oh you likely know but just to be sure, edge trailing only here. You don't want to be cutting the leather.

I think strops can be used both for edge maintenance and the final stage of sharpening. Now, in the case of the former, I would advocate to not rely on the strop for long periods of time. In other words, it's okay for a few weeks or whatever but you should do some touch up strokes on a higher grit stone every so often. The reason is you will eventually round over your apex and if you too awful long, you'll make sharpening more difficult due to the convexity you'll impart.

For the final step in sharpening, I recommend doing your best to deburr as best as you can on your stones. The strop should be seen as just that last little bit.

 

[Nemo]

I do strop, mainly for edge maintenance rather than for making a newly sharpened edge finer. I'm not sure I'd recommend it to a new sharpener. The three main problems are that it can can hide deficiencies in stone sharpening technique, it can draw out a wire edge and it can easily round the edge if you get the angle wrong.

This last problem is why I only ever use a strop without any "give". It's much easier to control the angle that the edge sees with a firm material. Examples of hard strops are balsa wood, very hard felt (mine is from Dave Martell- he called it "rock hard felt"), or even cereal box cardboard (use the light brown side, not the shiny side) or newspaper folded over the edge of the bench (maybe this is called a "counter" in the USA?).

I usually load the strop with diamonds in the 1-3um range. Not strictly necessary with cardboard or newspaper as these are naturally abrasive. Definitely helps with high alloy steel though.

Having said all that, some people do seem make leather or hanging straps work. I guess they get good at applying consistent pressure?

 

[JKerr]

Thanks for all the advice so far, it's greatly appreciated. I should mention that I'm confident in sharpening and deburring on synthetic stones, no problem getting to paper towel slicing or hair popping sharp with the stones I have though I seldom have the desire or need to take them that far other than for the fun of it. I definitely have a hell of a lot more to learn and improve on though and anything that improves the edge or maintaining between hitting the stones is a win even if that's even just a little.

It's good to hear the different impressions between suede and smooth leather and soft vs hard strops as that's something I was wondering about when looking at options. I just went for the leather as it was on sale.

Regarding the varies pastes/compounds, sprays. How long would you expect to get out of a bottle. For example, a 15ml Gunny Juice diamond emulsion retails here at $75AUD which is in new stone territory or Dialux bars are a humble $8. Obviously you pay for quality but are you going to get a similar life out of a bottle of diamond emulsion as you would a stone for the average once every couple weeks stone session?

 

[Matt Jacobs]

A bottle should last you forever. I really love this topic but the way and hope more chime in. One thing I find personally really interesting is at some point in my sharpening I learned that if I strop at a really high angle to the point where it goes from sounding smooth to actually hearing the blades scrape probably double the angle that I sharpened with. It made a huge difference in what I thought was sharpness. It immediately allowed me to pop hairs go through paper towels and even tissue paper and I thought I was the world's best sharpener. Eventually though I decided it actually sucked on tomatoes and pepper skin. For example, now I do a lower angle with the assumption that it's a soft substrate. So I'm getting a little bit of curling and I found that it allows me to deburr and still keep a very effective edge on tomatoes and peppers

 

[Nemo]

FWIW, I have used a small fraction of a bottle (maybe 10 ml out a maybe 100ml bottle) of 1um diamond spray in 5ish years.

 

[M1k3]

I have and occasionally actually use 2 balsa strops. One loaded with 1 micron, the other 0.25 micron.

That said, I'll usually just use a towel or piece of paper as a strop. For my use and preferences, this gives me the best balance of that little extra refinement, while keeping that "toothiness".

Or maybe I just suck with loaded strops?

 

[sumis]

i use everything in between sharpenings: cardboard, leather, my jeans, towels, koyo green stuff loaded suede, ceramic rod, bbw, dry sg4k, wet sg4k …
depends on mood, knife, steel, intended use, weather, politics, alcohol level.
i don't like smooth side of leather though.

useful comments above about angles

.

 

[Seemore]

I think stropping to deburr (during sharpening) and stropping to maintain an edge (while cooking) are different, at least conceptually.

To deburr I use the stone, then if necessary on a piece of denim stretched and tacked onto a board. It’s often necessary for me.

To touch up an edge (maybe every 3rd cooking session), I use a hard smooth leather strop. I flatten my stones after using them; I’ll often spread some resulting 2K or 3K stone paste over my leather strop and let it dry there. It lasts a long time. Either way, I strop VERY lightly for touchup.

 

[cotedupy]

A useful topic that isn't much discussed here, and some very good points already made, so I'm just going to pick up and expand upon a few made by @azn_knives_4l, @HumbleHomeCook and @Nemo.

Note that I don't strop loaded so don't know anything about that, this all refers to unloaded stropping. And I also don't use strops for 'touch-ups', though I know plenty who do.

---

Whether it's leather, or card, or newspaper the over edge of a work surface - make sure it has a hard backing. Hanging strops work for razors because the angle is set by the spine which eases pressure on the edge, and also because of what you're trying to do, which is polish out as much toothiness as possible. You don't want that on a kitchen knife generally, and also you're likely to continually nick a hanging strop with the heel of the knife.

Try to strop at the angle you sharpened at, maybe a touch below when you're starting out.

The idea that you should only strop at the lightest of pressure is fallacious ime. If stopping (hard-backed) at higher pressure but still at the correct angle f***s up your edge, then it wasn't a good edge to begin with and a board would've f***ed it up too. But nevertheless pressure does still make some difference to the outcome.

Paper and card seem to translate a particular stone's finish with greater fidelity, whilst leather stropped edges tend to all feel very similar, which of those is preferable is up to you.

Leather will ameliorate or hide small inconsistencies in your sharpening technique better than paper, card, cotton, linen &c, because it's simply better and more efficacious at stropping. Though that isn't necessarily to say it's always the best option. Leather tends to polish and refine an edge more than those other things, which leave more bite and teeth, though your deburring game has to be tip-top.

If using leather for kitchen knives use the suede / flesh side, not the shiny / skin side.

Just as you wouldn't finish every type of knife or steel at the same grit level, so too there isn't a catch-all solution for stropping. The variables (pressure, material, and presumably compound) affect different steels and different sharpening techniques in different ways. Below are some thoughts about what I find works well for me:

When stropping cheaper stainless I tend to use leather and higher pressure. For fancier stainless and carbon steels I tend to use paper or card. If finishing trailing I might be more likely to use leather, leading more likely paper. Likewise if finishing at a low grit I'd be more likely to use leather. But those aren't hard and fast rules; I choose how I'm going to strop based on a thumbnail test after final deburring, and that obviously takes practice and getting a feel for it.

And lastly, obviously, as with any of all this: personal preference is the overriding factor. Once you're happy that you can hold an angle properly - play around with some of these different aspects, see what you like for your own knives and edges.

 

[azn_knives_4l]

A useful topic that isn't much discussed here, and some very good points already made, so I'm just to pick up and expand upon a few made by @azn_knives_4l, @HumbleHomeCook and @Nemo. I don't strop loaded so don't know anything about that, this all refers to unloaded stropping. And I also don't use strops for 'touch-ups', though I know plenty who do.

Whether it's leather, or card, or newspaper the over edge of a work surface - make sure it has a hard backing. Hanging strops work for razors because the angle is set by the spine and because of what you're trying to do, which is polish out as much toothiness as possible. You don't want that on a kitchen knife generally, and also you're likely to continually nick a hanging strop with the heel of the knife. Paper and card seems to translate the stone's finish with greater fidelity, whilst leather stropped edges tend to all feel very similar, which of those is preferable is up to you.

Try to strop at the angle you sharpened at, maybe a touch below when you're starting out.

The idea that you should only strop at the lightest of pressure is fallacious ime. If stopping (hard-backed) at higher pressure but still at the correct angle f***s up your edge, then it wasn't a good edge to begin with and a board would've f***ed it up too. Though that's not to say that pressure doesn't make some difference to the outcome.

Leather will ameliorate or hide small inconsistencies in your sharpening technique better than paper, card, cotton, linen &c, because it's simply better at stropping. Though that isn't necessarily to say say it's the best option. Leather tends to polish and refine an edge more than those other things, which leave more bite and teeth, though your deburring game has to be tip-top.

If using leather for kitchen knives use the suede / flesh side, not the shiny / skin side.

Just as you wouldn't finish every type of knife or steel at the same grit level, so too there isn't a catch-all solution for stropping. The variables (pressure, material, and presumably compound) affect different steels and different sharpening techniques in different ways. Below are some thoughts about what I find works well for me:

When stropping cheaper stainless I tend to use leather and higher pressure. For fancier stainless and carbon steels I tend to use paper or card. If finishing trailing I might be more likely to use leather, leading more likely paper. Likewise if finishing at a low grit I'd be more likely to use leather. But those aren't hard and fast rules; I choose how I'm going to strop based on a thumbnail test after final deburring, and that obviously takes practice and getting a feel for it.

And lastly, obviously, as with any of all this: personal preference is the overriding factor. Once you're happy that you can hold an angle properly - play around with some of these different aspects, see what you like for your own knives and edges.

Wouldn't it be cool if we could compile all of this individual research??? Too bad so little of it translates due to differences in preferences and everything else. Broad strokes appear reductive on the surface but I think it's about as good as we're going to get. Maybe we can look to sculpture? They've used abrasive powders on various substrates to exceptional effect for centuries now. Or maybe all of that is pointless, too, because of the sub-micron scale that we're working with...

 

[HumbleHomeCook]

Thanks for all the advice so far, it's greatly appreciated. I should mention that I'm confident in sharpening and deburring on synthetic stones, no problem getting to paper towel slicing or hair popping sharp with the stones I have though I seldom have the desire or need to take them that far other than for the fun of it. I definitely have a hell of a lot more to learn and improve on though and anything that improves the edge or maintaining between hitting the stones is a win even if that's even just a little.

It's good to hear the different impressions between suede and smooth leather and soft vs hard strops as that's something I was wondering about when looking at options. I just went for the leather as it was on sale.

Regarding the varies pastes/compounds, sprays. How long would you expect to get out of a bottle. For example, a 15ml Gunny Juice diamond emulsion retails here at $75AUD which is in new stone territory or Dialux bars are a humble $8. Obviously you pay for quality but are you going to get a similar life out of a bottle of diamond emulsion as you would a stone for the average once every couple weeks stone session?

They'll last a really long time. @Deadboxhero is a fan of Gunny Juice and that's a fine endorsement. That said, not sure I'd be up to dropping $75 on a bottle...

On a somewhat related note, if you want to play with stropping on other substrates, a sharpener I really respect saves the slurry from his sharpening, smears it into whatever (newspaper, cardboard, wood, etc.) and lets it dry.

 

[drrayeye]

Stropping is no substitute for sharpening.

As a low volume home cook, I rely on a loaded strop--mostly green--to refine and maintain on the rough side--and the smooth side to polish. I now have three strops--all mounted--each one longer and wider than the last. I use the smallest for heavily loaded compound only; the next with compound on the rough side--smooth side for polishing; and the largest without loading on either side--for finishing.

Since I rely on my knives to be sharp, my loaded stropping, carried out very regularly, is sufficient to delay sharpening indefinitely on my harder steel knives. My softer steel knives are sharpened and honed and then mostly stropped unloaded for polishing.

The slight convexity strops impart to my hard steel knives mostly refines edges that already have some convexity--and have been an advantage--not a problem.