Stropping Forever? (Forever ever? Forever ever ever?)

[Sharperthansticks]

By way of introduction, I consider myself an advanced beginner/beginning intermediate sharpener, so, on an expertise scale of 1 - 10 for sharpening, I'd rate myself a 4. I've used a WorkSharp KE with blade grinder, and I've used a KME.

Stones have always been my friends on the KME. (Most of the time, I find that the 1500-grit by itself is just fine to sharpen just about anything, within a few minutes.) My expertise breaks down at strops and lapping films. (I have both for the KME but am not that great with either.) I don't think I reliably get my knives sharper than about 5,000 grit (and 5,000 grit may be an overstatement. My knives will shave arm hair, but I don't think they get sharper than that).

Just bought some free-hand strops. Here's my question: people talk a lot about only needing to touch up a knife with frequent stropping; if one were to strop religiously, could one completely dispense with the rest of sharpening -- sharpening on stones or diamonds -- assuming the edge isn't chipped? Put another way, if you only cut materials that dulled your knife but did not chip it, could you only strop, never resorting to stones again?

 

[kreisler]

if you only cut materials that dulled your knife but did not chip it, could you only strop, never resorting to stones again?

i would say yes, especially with a wood strop instead of a leather strop. a leather strop polishes and micro-convexes the apex: leather stropping basically forms a new apex with a less acute angle. a wood strop is hard and you can strop the edge at the exact edge angle, not forming a micro-convex apex.

 

[sickpuppy1]

Even with a leather strop, if it’s forming a convex edge you’re pressing too hard or turning the blade during the stroke.
I use my knives hard so unless I strop 10 times a day, I will need a stone. And my hapstone m2 fills the billl nicely. Now that being said, 90 percent of the time I don’t go below the 600 stone unless it’s chipped, and then the 1200 and stop with green and plain leather.

 

[brando555]

Stropping can definitely bring a dull edge back into a decent working edge, especially a hard backed leather or balsa strop with diamond compound.

I still prefer something like a ceramic rod for a quick touch up though.

Eventually you're going to need to go back to the stone at some point. No way around that.

Just my $0.02.

 

[lex2006]

I am doing this experiment now , started with a new small 21 in May . Has only been stropped with flex cut on leather im guessing about 10 times and diamond spray on leather 2 or 3 times just to see how it compare.
Just this last weekend I finally got the last few nicks out from the factory grind
I can post a photo tonight if anyone is interested.
This knife gets used daily , mostly opening boxes , straps , packaging and stripping wire.

 

[Obsessed with Edges]

Aside from actual chipping or other real & obvious damage, part of the 'dulling' of an edge comes from minute amounts of abrasion against the apex, due to dust, dirt or anything moderately hard enough to slowly alter the shape of the steel there. Over time, that'll cause the apex to flatten, round over, burnish or develop irregularities (dents, misalignment) that will diminish sharpness.

Some forms of stropping can stay ahead of that for awhile, reducing the necessity or urgency to frequently resharpen on a stone. But, if the knife gets used much at all, there'll come a time when the strop won't be able to fully restore the sharpness as it originally existed on the newly-sharpened edge. Too much stropping will eventually polish the micro-teeth out of the edge, which will reduce it's aggressiveness in cutting (slicing cuts especially). This is likely what you'll notice first, in determining the edge isn't the same as it once was; it won't have the same 'bite' anymore. Taken further with more use, the edge will eventually round over or flatten to the extent that it won't hardly cut at all anymore, except with much more force applied. A strop won't likely fix that, unless it's very firm or hard and is used with very coarse & aggressive compound (effectively sharpening more like a stone would). But even so, a stone will still be the quickest path to fully reshaping the edge geometry to a crisp apex, with all it's aggressive teeth back in place.

The convexing occurring on an edge from a lot of stropping will get even more so, the more often the edge is stropped. And while the crisp & sharp apex retreats as it wears away in use, the 'shoulders' of the convex get rounder from all the stropping. That'll effectively widen the edge geometry over time, while also rounding & dulling the apex.

 

[Bigfattyt]

I've found that with frequent use of a strop, I still occasionally need to use a stone or ceramic stick to get the bite back in the edge.

 

[ndmiller]

For my good steak knives which dull as used on plates I realign edge with steel and strop every 3-4th use. Haven't used a stone or actually sharpened in years, but that's a very specific case.

Other kitchen knives I align on steel & strop regularly, only sharpen Santoku and Chef on stones maybe twice a year.

I regularly strop my CRK Inkosi, again had for years never sharpened. I use it, but not real hard use. Amazon box tape breaks cleanly no knife needed......

For my hard use outdoor blades I use them hard (mostly wood prep and whittling/try sticks and some food prep), sharpen on a stone (Insert Favorite Spyderco setup I have them all) and strop regardless of need before every outdoor trip.

I've found regular easy maintenance (<5 min) is much better than irregular 20+ minute sharpening sessions when it comes to all knives and cutting tools. Just don't have the blocks of time I used to with everybody's needs in the family.

 

[Wowbagger]

I would say no.
We had a major (long) strop at work we used for years for box knives. The strop was loaded with the best stick abrasive I've ever run across . . . it is Gold something or other . . . I'll look it up again if you care. I do that for people once or twice a year. it's mostly for wood carving tools.

What I wanted to say is, because the box knives were so thin and the sharpening bevel so laid back the stropping worked fairly well for us.

Thicker knives . . . now . . . I find stropping to be extremely limiting.
Why ? ? ?
Well to start the bevels are pretty obtuse.
One of the most effective things I FINALLY learned about sharpening was to go fairly coarse to set the bevel and apex the knife (or for apex sharpeners to nearly apex the knife . . . not a negative comment I respect the apex method). Fairly coarse meaning 320 or even 220.

I started in to sharpen a brand new Buck knife a couple of nights ago, I was following the factory geometry (not reprofiling) and I started with a 60 grit Gritomatic ruby stone because the edge was kind of wavy (not saying anything against Buck; the edge over all was great / pretty darned sharp and no burs or rolls).

What I am saying is if I had taken the edge to a hard strop there would have been areas of it that would not have gotten stropped because it would never have touched the strop.

As an edge is resharpened the angle tends to get more obtuse and the coarser stone is required to knock the shoulder / angle back to something that is effective.

Sure one can get . . . literally . . . hair whittling edges on obtuse edges, think 54° inclusive, but that geometry sucks for actually cutting many materials. Hairs are super thin and flexible to shave curls off of but take that edge to a piece of thick leather or rope or what have you and it stalls right out.

The other thing about stropping is once you get to where you are stropping the whole sharpening bevel and not just a micro bevel right near the edge metal from all that wide bevel loads up the strop and over powers the little non fixed particles of sharpening grit and the effect is diminished.

I much, much, much, much prefer grit that is fixed onto a hard stone or metal plate that can't roll around or get smooshed into the backing. Leather, cloth, soft wood or hard wood are all just a bit too prone to gobble up the abrasive for my taste.

Yes give me stones and fixed abrasive any day.

Bottom line strops suck and using only strops to sharpen sounds like a night mare to me.

 

[HeavyHanded]

With a very hard strop, you can maintain cutting edge geometry for a long time. You cannot do this with leather, as you will need to be able to lean on the surface a bit if you have any hope of removing steel from behind the cutting edge - (this will be 100% necessary at some point fairly early in the process). As you use a knife it creates a wear bevel at the apex. Cleaning up this bevel as it dulls won't restore the geometry. Continued use creates another wear bevel on top of the original, after a couple reconditionings the angle at the apex will be overly broad.

You will need an easily cleaned or replaceable surface as it will load up rapidly. Paper over a coarse stone is a good option, as is a piece of roughed up hardwood. Communities that didn't have access to good quality stone slab for making sharpening stones did very well using silica sand on a piece of wood, a sharpening board. You can do a lot of grinding and honing using this method, from butterknife dull to whisker-shaving sharp (if you have some hot lather around!).

I've maintained several machetes and a couple of broad bladed convex and Scandi knives for years at very high levels of edge quality using nothing but paper over one of my old Washboards - paper over a very coarse stone is the next best thing. Using a strop for maintenance also has challenges to the user as there is very little feedback. If you begin to make the angle too broad it is very difficult to bring it back on just a strop. You need a surface hard enough to work the region just behind the apex, with a very small abrasive it really helps if you can get on it.

 

[ToddS]

There is really no difference between a hard substrate loaded with abrasive and a "stone." MDF loaded with polishing compound makes a poor-man's high-grit stone.
You could argue that any substrate that you do edge trailing strokes on is a "strop" - although I don't subscribe to that view.

I define a strop as a substrate that produces micro-convexity. That can be wood, if there are loose fibers on the surface that produce a thin, compliant layer. It certainly includes paper, fabric and leather.

Just like a honing rod, stropping removes a small amount of steel at the apex to restore keenness, and this only works for so long before you need to thin (sharpen) the bevel again.