Down the rabbit hole - deburring/stropping

The two most fundamental tenets of sharpening, IMO, are these: 1) 95% of sharpening is done on the coarsest belt or stone and 2) deburring is the main thing that separates a tolerable edge from a great one. On stones I do the bulk of deburring with ever-lighter alternating passes on the stone. I do this on each succeeding stone for the most part. The last stropping is usually done on a kangaroo strop with fine diamond or CBN emulsion.

On belts I generally use the following progression: Cubitron P120 > Trizact A30 > felt belt doped with 3 micron CBN or diamond emulsion. I'll often follow up with a double-sided hand strop with kangaroo doped with 0.5 micron StroppyStuff and StroppyStuff 9 micron on the rough side. Most of the knives I sharpen for customers get this treatment unless they request hand sharpening. I don't have a BESS Testor although I am considering getting one. I based my system on Cliff Curry's system, having watched his videos for awhile before flying out to train with him in Hawaii. He gets under 100 on the BESS using this system minus the hand stropping (he never hand strops to my knowledge). To be honest it might just be habit or superstition but I just don't feel like the job is "done" until I've hand stropped the knife.🤫

I do have Scotchbrite wheels but I only use them for deburring on garden tools for the most part. I know Cliff sometimes uses them this way which is maybe why I sometimes feel the need/desire to finish with a hand strop. Occasionally I use a rock hard felt wheel doped with 3 micron CNB spray when I want a "slicker", less toothy edge. Usually I aim for a bitey/toothy edge when sharpening wiht powered gear.

Before stumbling on Cliff's videos about edge-leading belt sharpening I'd been doing it edge-trailing for 20-some years and deburring on a leather belt doped with HandAmerican Green Chromium (it came in a bottle like Elmer's Glue). "Serious" sharpening I usually did on stones with belts being reserved for house knives and tools. Interestingly it took a while to get used to a felt belt, it just didn't feel right. But after I'd been using felt in my shop for a year I decided to try a leather belt again and I now hated it. 🤯 Initially I tried felt because it doesn't stretch and can be left on the machine all the time. Eventually I came to prefer the performance. I feel like the leather is faster and more agressive when deburring I feel like it's maybe too agressive compared to felt. The felt belts have tremendous life, too. I used one for a year and it was still working but starting to get kind of gunked up so I switched out to a new one.

I've been sharpening for at least 25 years or more but I still find there's more learn.
 
Thanks for the suggestions. I started off trying the wheel after seeing Cliff Curry's process. He typically deburrs with the green Scotch Brite wheel.

I wasn't having good luck with the wheel. This was before getting the BESS tester and before getting a lower speed grinder. I could feel the change in sharpness after using the wheel. I believe I was applying too much pressure for the speed of the wheel on that grinder. I now have another grinder that moves slower. Will have to give that a try.

Bruce
 
I don't sharpen or strop with powered belts or wheels, so my results may not translate to those that do.

I've gotten some of the best results with lapping film on glass. The hard substrate and thin film seem to hold the abrasive surface mostly off the apex, so it doesn't wrap around the edge. This makes getting the ideal pressure much less of a problem. If you get the first stages (the most coarse stages) right, meaning there is a crisp, honest apex, the lapping film stropping process seems to clean away anything that shouldn't be there with no drama and no rounding of the apex.

Lapping film is available with AO, SC, or diamond abrasives and I am slowly getting a feel for which variety works best on different steels. It also seems to be the most reliable way for me to get a brilliant, reflective shine, if appearance matters!

I think my life would be a lot easier if I only owned knives made of one steel, with all of them treated to the same hardness. It is way too late for that now!

I have experienced that problem where a stropping stage raises my BESS score rather than lowering it. The only explanation I can suggest is that particular stage may have "broken off" a foil edge, leaving behind a flat surface where the apex should be.
 
A keen edge is all about the finish. Some guys seem to be able to strop with stones… whatever works. For me, the success comes when you get the right angle with a good media and the correct pressure. It seems as though every metallurgist that has ever walked the earth created his “best” steel. Every steel responds differently to grinding/stropping. Buck knives will take more pressure stropping than a Smith and Wesson. Stainless is the worst. Maybe the higher vanadium makes those burrs want to hang on, but they’re a pain for sure. The bottom line is, if you can’t generate the numbers you want with what you’re doing, you gotta change something. For me, it was both the angle and the pressure. (Compounds and emulsions do make a difference, but are not deal breakers. That’s to say, results will come faster with some pastes vs. others.)
When chasing a low Bess score, I find that progressively lightening the pressure to the point of no pressure can really help when stropping on a wheel. The belt is tougher for me and more random as you’re dealing in quarter microns. Unless you’re using a controlled angle, you’re going to have variances (and even then.) Some guys are better than others but I believe anyone can eventually get there.
I said all that to say everyone does it differently. Focus on what matters, angle and pressure, and you will arrive. You do need some decent equipment so you don’t pull all your hair out, but the process just boils down to those two critical components. IMHO
 
A great dal of useful knowledge getting passed down here and truth be told, you will almost always run across new wisedom, processing, for me, I have a few of the knife shapening sytems that you pull or stroke the blade with not very wide gauged tools that do some of the work, but, I have found those type of sharpening "systems" are not so good, the pressure assigned to eack stroke may overlap, miss,etc.

And then I found a roller syste where one half of the rollers are assigned your angle of attack, keeping everthing in timing as to the pressure, and coverage to really help get your desired degree unified. Nothing how ever stop my use of stones or diamond plates.

Once things start to give what is needed, you've learned the skill set to obtain that nice, smooth fine shiny edge after that final strop.

Going back in time, I came across a strop/sharpening pudding like compoud from a japanese supplier that a world famous shusi chef that uses it to keep his knife really sharp. Now we may not have his extreme needs, and those shusi blades are never going to do bushcrafing,but his technique is very good information and a pleasant presentation on how to keep ahad of the venture of sharpness! I do not recall his YouTube but if you look around, you might find him, his product label is not in english but I should be able to find it KOYO Stainless Steel Polishing Compound 100ml cleaner NEW on ebay. I spent a ton of money on gun, knife, computers. For me this product really works.
 
Gottagofishn said:
A keen edge is all about the finish. Some guys seem to be able to strop with stones… whatever works. For me, the success comes when you get the right angle with a good media and the correct pressure. It seems as though every metallurgist that has ever walked the earth created his “best” steel. Every steel responds differently to grinding/stropping. Buck knives will take more pressure stropping than a Smith and Wesson. Stainless is the worst. Maybe the higher vanadium makes those burrs want to hang on, but they’re a pain for sure. The bottom line is, if you can’t generate the numbers you want with what you’re doing, you gotta change something. For me, it was both the angle and the pressure. (Compounds and emulsions do make a difference, but are not deal breakers. That’s to say, results will come faster with some pastes vs. others.)
When chasing a low Bess score, I find that progressively lightening the pressure to the point of no pressure can really help when stropping on a wheel. The belt is tougher for me and more random as you’re dealing in quarter microns. Unless you’re using a controlled angle, you’re going to have variances (and even then.) Some guys are better than others but I believe anyone can eventually get there.
I said all that to say everyone does it differently. Focus on what matters, angle and pressure, and you will arrive. You do need some decent equipment so you don’t pull all your hair out, but the process just boils down to those two critical components. IMHO
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Amen!
 
Gottagofishn said:
Love the variable speed machines. I can slow grind and kick it up a notch for stropping.
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If a person wants to try that system, they can buy some cheap blades and see here it goes. For me,, I hesitate use of any power based grinding, too chicken I guess, I own several electrified, Frankenstein contraptions and as they have been great collecting dust-bunnies, I think I will put them up for sale dirt cheap, they are all new with al the goodies included, but I know you are an expert compared to me!
 
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