Stropping with diamonds leaving a burr..wtf?

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yepimonfire

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Nov 7, 2013
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I've been using white compound to finish off my knives, this leaves behind an excellent burr free edge. Plain ole white crayon stuff. Wanted to take it to the next level so I got some 1 micron and .5 micron diapaste, no change in strops or method, and now the damn things are snagging in paper like any burr ridden knife does, this is by further stropping an already white rouge stropped edge, so it was burr free before the diapaste. Any ideas?
 
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Am guessing it still had remnant burring left prior to the diamonds and the white compound may have just smoothed it into a wire edge.

Also possible - when working on low Vanadium carbide steels those diamond will not work like the white compound, even at the same particle size. All else being the same they cut a little deeper. Is possible they could be raising a burr, but generally one has to have a very hard backed strop, or a very large abrasive size to make a burr where none existed.
 
There was no burr or wire edge before, been stropping it on the white compound and getting good edges for months. I was stropping low vanadium carbide steel, Aus 8a and 8cr13mov. The strop is relatively hard backed, denim wrapping an Arkansas stone. I went back and forth between the two several times and after 10-15 swipes on the diamond the problem occurred again, going back to the compound the same number fixing the problem.
 
i am not too surprised that diamonds, even that small, can produce a burr on hard backing on a softer steel although I assume they should sink into the denim quite a bit. Maybe the paste bond type is the problem that "keeps them on the surface"? I know that is useless information but I bet that if you used compatible particle size in Boron Carbide you would not have the problem.
 
I'm guessing it's a problem of very hard material on soft low wear steels. I've always been left with a burr off my 3 micron 8k waterstone as well, which is also a very hard material, no matter how easily I finish with it. Reason I got the strop. Seems the softer the steel the worse the burr as well. I haven't used the diamond on my s30v blade yet, which is what I got it for so maybe it would result differently.
 
Try the compound on paper over Martin's washboard or compound on single layer cardboard, similar to those tissue paper or cereal boxes over hard backing (hard wood/glass). I also mostly deal with 8Cr type of steel & doing up to 1 micron it works well.

One question, how do you spread the compound?
 
Chris "Anagarika";14304504 said:
Try the compound on paper over Martin's washboard or compound on single layer cardboard, similar to those tissue paper or cereal boxes over hard backing (hard wood/glass). I also mostly deal with 8Cr type of steel & doing up to 1 micron it works well.

One question, how do you spread the compound?
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Just work a thin amount into the denim. What is the washboard?
 
yepimonfire said:
There was no burr or wire edge before, been stropping it on the white compound and getting good edges for months. I was stropping low vanadium carbide steel, Aus 8a and 8cr13mov. The strop is relatively hard backed, denim wrapping an Arkansas stone. I went back and forth between the two several times and after 10-15 swipes on the diamond the problem occurred again, going back to the compound the same number fixing the problem.
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Try using the denim & diamond compound on a firm, but slightly less-hard backing like wood, instead of the Arkansas stone. Between the deeper cutting done by the diamond on the softer steel, and the pressure created against the stone, I'm betting it's the combination that's causing the (bigger, more noticeable) burr to form. Pressure is what creates burrs and is also what makes them bigger than they might otherwise be.

Aside from the above, diamond is somewhat overkill on the steels you mention. The white compound should work much better for them; and if wanting to refine a little more beyond the white, use green compound instead of the diamond.

In general, anytime I see burrs forming where they weren't before, I ALWAYS look to reduce pressure in one way or another; either by lightening up with the hands, or reducing the hardness of the backing upon which I'm working, or a combination of those two. It always makes a difference.


David
 
yepimonfire said:
I'm guessing it's a problem of very hard material on soft low wear steels. I've always been left with a burr off my 3 micron 8k waterstone as well, which is also a very hard material, no matter how easily I finish with it. Reason I got the strop. Seems the softer the steel the worse the burr as well. I haven't used the diamond on my s30v blade yet, which is what I got it for so maybe it would result differently.
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If it keeps coming back to the diamond, then you have to assume it must be the culprit. On that tack you could try the diamonds on your s30v using the same methods and see what happens. FWIW, I've never seen any advantage to using diamonds on 'regular' steels. AlumOx or properly managed SiC seems to work a lot better, though I also haven't experienced any issues with burring off of fine diamond compound either...

Another option might be to work a drop or two of oil on the strop to give the diamonds a bit more mobility, but that method might not work so well on denim.

Can you see a difference in the finish when you go from white compound to the diamonds - is it visibly becoming less polished?
 
HeavyHanded said:
If it keeps coming back to the diamond, then you have to assume it must be the culprit. On that tack you could try the diamonds on your s30v using the same methods and see what happens. FWIW, I've never seen any advantage to using diamonds on 'regular' steels. AlumOx or properly managed SiC seems to work a lot better, though I also haven't experienced any issues with burring off of fine diamond compound either...

Another option might be to work a drop or two of oil on the strop to give the diamonds a bit more mobility, but that method might not work so well on denim.

Can you see a difference in the finish when you go from white compound to the diamonds - is it visibly becoming less polished?
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More polished. I'm going to try a softer surface.
 
Ok a bit of experimenting:
I tried Aus 8a with soft backing, less burr, but still problematic, even light touch. I gave my s30v blur about 30 swipes and no burr, in fact, I didn't really notice much at all happen with it, it got very slightly sharper but it wasn't dull to begin with. Seemed like the diamond had minimal effect, like you'd expect with a strop. So it must just be super hard abrasives on soft steel is the problem. This also may solve my super soft kitchen knife dilemma, no matter what, even with the white compound, there still remains a small burr. Is there anything softer than white rouge I could try out on those?
 
yepimonfire said:
Ok a bit of experimenting:
I tried Aus 8a with soft backing, less burr, but still problematic, even light touch. I gave my s30v blur about 30 swipes and no burr, in fact, I didn't really notice much at all happen with it, it got very slightly sharper but it wasn't dull to begin with. Seemed like the diamond had minimal effect, like you'd expect with a strop. So it must just be super hard abrasives on soft steel is the problem. This also may solve my super soft kitchen knife dilemma, no matter what, even with the white compound, there still remains a small burr. Is there anything softer than white rouge I could try out on those?
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Soft stainless kitchen knives don't usually polish up well, for the reason you've seen. Even if no burrs are initially present after polishing, the very thin & fine edge dulls and rolls easily. I've abandoned any efforts to polish mine, and found a coarser finish around ~320-grit or so is a better fit for such blades, applied with a feather-light touch. Very, very light passes on a diamond hone or rod, or on a SiC stone, are a quick & easy way to do it. If you strop at all, just use bare leather, or clean paper on a firm backing, with no compound. Or, if you use a compound, use something that's minimally aggressive, like green compound.


David
 
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Yep , it can happen. And that's just with Dia-Paste :p

Lower your pressure significantly , and start alternating strokes. Do many many extremely light alternating strokes. You should be able to work it away.

If not go back to your finest stone and do extremely light , alternating edge leading strokes. The proceed onto the diamond and skip the white crap.
 
What I did to mine (Resilience, SanRenMu):

- Finish on DMT EEF (3 micron mesh) edge leading to remove burr as much as possible
- Strop with 3 micron to reduce the scratch pattern, then clean the blade, move to 1 micron, moderate to light pressure.

I am guessing here: smearing the paste on jeans might be more challenging than on the back of single layer cardboard like what I use. It might contribute as well (paste lumping in some areas). Using oil to spread the paste more uniformly might help. Further, burring as function of edge geometry is worth to look at, as some blade might have different optimum apex angle that can be stropped without resulting in burr. You might find this old thread useful:www.bladeforums.com/forums/showthread.php/992879-Apex-Bevel-Geometry-cross-sectional

I have yet tried my AUS 8, but trying same process with SuperBlue (Endura) & M4 (Gayle Bradley) yield slightly different result. It might be the steel & heat treatment characteristic.
 
Obsessed with Edges said:
Soft stainless kitchen knives don't usually polish up well, for the reason you've seen. Even if no burrs are initially present after polishing, the very thin & fine edge dulls and rolls easily. I've abandoned any efforts to polish mine, and found a coarser finish around ~320-grit or so is a better fit for such blades, applied with a feather-light touch. Very, very light passes on a diamond hone or rod, or on a SiC stone, are a quick & easy way to do it. If you strop at all, just use bare leather, or clean paper on a firm backing, with no compound. Or, if you use a compound, use something that's minimally aggressive, like green compound.


David
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A stout burnishing with plain paper works great coming off a medium finish - don't spare the elbow grease. Another good option with the low RC kitchen fare is to hit them with a smooth steel coming off the medium finish. The edge of some Pyrex, rim of a glazed ceramic bowl etc work great. That bit of work hardening really seems to help longevity on the lower RC stuff.

Is all trial and error, one of my sets is much better quality steel but cannot tell by looking at it. I treat it just like all my sport cutlery and finish with a hard strop - works great.
 
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