Stropping question for coarse, "toothy" edge

[Strauss95]

Got a quick question when it comes to stropping a coarse edge finish. I've dedicated myself to only freehand sharpening over the past couple of months, working with lots of high vanadium content steel. I've been slowly working my way down to coarser edge finishes on them, getting my best edge results coming off a DMT fine and or Venev F400. Since I'm far from a master freehand sharpener I still struggle with getting a completely burr free apex directly off the stone, and the coarser the stone the more difficult it is for me. With that being said, I typically finish my edge with some light stropping on either firm leather or balsa wood with diamond emulsion to help get rid of any remaining burr. My question relates to the micron size of the diamond emulsion.

With my goal of maintaining the aggression of the toothy edge finish, which micron size would be best to strop with? Currently I'm using 1 micron (Gunny Juice), but wasn't sure if a more coarse or fine emulsion would be better to preserve the bite?

My internal debate was a 3 or 4 micron emulsion would obviously be more coarse but wondered if it would remove more of the bite compared to a finer grit due to it working "too well"? Or would it actually leave me with a more aggressive edge compared to 1 or 0.5 micron?

I know the obvious best case scenario is coming off the stone clean and completely burr free for the most amount of bite, but I'm not quite there yet in my skill level freehand. I struggle with the softer stainless steels mostly, when sharpening friends cheap folders and kitchen knives. I've been obsessed with sharpening for over 10 years, but have been freehand sharpening for only the last 2 or 3. But I always fell back to my guided systems as a crutch, only recently have I committed to it so I can become 100% confident in doing so.

 

[catspa]

On the softer stainless steels, you might try burnishing with a butcher’s (smooth) steel. In some cases it almost “smears” the microscopic edge.

Personally, I use a trailing stroke which seems to require perhaps 1/3 more strokes than leading for equal results. My favorite steels are antiques (I favor F. Dicks from between the wars) and have pitting and other flaws that I don’t want to jam my edge into forward. Trailing, the edge just bounces over any damage.

I sharpen freehand also, and many times I find that a few burnishing strokes before going to the stones allows me to get sharp with less edge removal.

Give it a try, see if it helps.

Parker

 

[Strauss95]

On the softer stainless steels, you might try burnishing with a butcher’s (smooth) steel. In some cases it almost “smears” the microscopic edge.

Personally, I use a trailing stroke which seems to require perhaps 1/3 more strokes than leading for equal results. My favorite steels are antiques (I favor F. Dicks from between the wars) and have pitting and other flaws that I don’t want to jam my edge into forward. Trailing, the edge just bounces over any damage.

I sharpen freehand also, and many times I find that a few burnishing strokes before going to the stones allows me to get sharp with less edge removal.

Give it a try, see if it helps.

Parker

Will do, thanks for the tip!

Still interested if a lower or higher grit diamond emulsion is better to preserve edge bite. I know it will be best to limit the amount of stropping strokes no matter the grit, but curious which is best.

 

[Blade Lab]

Personally I would go in the opposite direction. Strop with 7 or 15 micron, and no more than 2-3 strokes per side.

 

[Ourorboros]

Since your goal is to work off the burr and not a finer edge, you don't need to worry about the carbides.
Bare strop.
If you apexed the edge, you already have the edge you want on the other side of that burr. You aren't trying to refine the edge, so nothing on that strop. It's merely acting as a surface to fatigue off that burr.

 

[Obsessed with Edges]

As suggested above, a bare strop is best for fully preserving the toothy aggression off the stone, if you like how it cuts. And to make that work well, it's also important to thin & reduce the burr as much as possible on the stone, before taking it to the bare strop. Most stropping on leather or other soft substrates, even with relatively large-grit compounds, will reduce & alter the toothy bite somewhat - and sometimes a LOT. So, the bare strop is better for preserving the bite in the edge left by the stone. A soft substrate like leather is essentially like a pillow under the blade, and even coarse compounds will imbed deeply into it, which greatly reduces the compound's exposure above the substrate surface and therefore its effective grit rating. Therefore it'll trend more toward polishing than cutting deeply. This is why a toothy bite in an edge is better produced and maintained with a stone, rather than with a loaded strop.

An effective alternative to stropping is to finish 1 step coarser on the stones than you otherwise would - like on a Coarse DMT instead of the Fine. Minimize the burr as much as you can and then use a medium brown/grey ceramic hone with extremely light touch, and with no more than a couple or three passes per side, to put an almost-nothing microbevel atop your coarse edge. I've come to prefer deburring that way, for the most part. And the microbevel will also narrow the apex width on top of that toothy bite, which enhances slicing aggression while also helping to stabilize the edge. But it's critical to keep those finishing touches on the ceramic to an absolute minumum, so you don't take too much of that tooth away. This is something fun to experiment with for awhile, so you can get the sense for the light touch and the minimal passes required to make it work well.

Edited to add:
Some combinations of steel type vs. compound used can reduce the toothy bite in the edge very quickly - even in just a handful of passes. You can test how the cutting aggression changes with slow cuts in fine paper after every 1-2 passes on the strop, to gauge the effect of the compound on the steel. For example, even a mildly-aggressive polishing compound, like green compound on leather, can quickly overpolish the bite out of a simple steel like 1095, CV or stainless like 420HC sharpened on a stone like a Fine India. I used to strop with green compound on a leather belt for steels like this. But I figured out pretty quickly, I prefer the 360-400 grit tooth straight from the stone, which the compounded strop would otherwise erase very quickly. The bare leather does a better job with the burrs and their weakened remnants, without otherwise altering the tooth in the edge much, if at all.

 

[yepimonfire]

Just pick a compound and use it. Doing 50 passes per side will clean up the edge without polishing the teeth off. If you stop at 600, you'd have to go through a full polishing progression with multiple compounds to actually remove the teeth, and even then it'd probably still be somewhat toothy. I stop at 1200 grit diamond and then strop on 3, 1, .5, and .1 micron and I still have a fairly toothy edge.

If I go waterstones at 220/1k/4k/8k and then strop with the same progression I get a true mirror polished edge with minimal teeth.

 

[chalby]

As suggested above, a bare strop is best for preserving the toothy aggression off the stone. And to make that work well, it's also important to thin & reduce the burr as much as possible on the stone, before taking it to the bare strop. Most stropping on leather or other soft substrates, even with relatively large-grit compounds, will reduce the toothy bite somewhat - and sometimes a LOT. So, the bare strop is better for preserving the bite in the edge.

An effective alternative is to finish 1 step coarser on the stones than you otherwise would - like on a Coarse DMT instead of the Fine. Minimize the burr as much as you can, and then use a medium brown/grey ceramic hone with extremely light touch, and with no more than a couple or three passes per side, to put an almost-nothing microbevel atop your coarse edge. I've come to prefer deburring that way, for the most part. And the microbevel will also narrow the apex width on top of that toothy bite, which enhances slicing aggression while also helping to stabilize the edge. But it's critical to keep those finishing touches on the ceramic to an absolute minumum, so you don't take too much of that tooth away. This is something fun to experiment with for awhile, so you can get the sense for the light touch and the minimal passes required to make it work well.

^^^ This is more or less what I do.

I would minimize the burr on the stone you want to finish on: 2-3 edge leading strokes at the same angle as you sharpened, or very slightly more obtuse angle(making a slight micro bevel) with as little weight on the knife as possible whilst making constant smooth contact with the edge. Then 2-3 light strokes(edge trailing obviously) on a strop at the sharpening angle or very slightly more narrow angle(laying the blade very slightly flatter) if using a softer substrate like leather.

Edit: It helps to weaken the burr whilst sharpening as well. Once you have the burr on both sides, keep working on each side a few times, gradually reducing pressure and time on each side before the above steps. This will reduce and weaken the burr and make it easier to refine you edge in subsequent steps and give you a better, sharper edge at the end.