Wire edge that won't go away

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Oct 20, 2004
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I am giving my walmart native with S30V steel a good sharpening with my lansky multi-angle sharpener.

I have developed a wire edge with the medium stone and have tried to remove it. I will turn the blade over to remove the edge and give it a couple passes and you can feel the edge disappear. I then turn the knife over and it has just pushed the edge to the other side. I have repeated this numerous times and it just keeps getting pushed to the other side without coming off. I also tried using the fine stone with same results.

Any ideas? I planned on removing the edge and then going down thru the ultra fine stone and finishing with a strop on a uncharged piece of leather.

Any help is greatly appreciated as I don't know what I'm doing wrong. Thanks!

Ryan
 
maybe try going really light on the side with the wire one time at a little bit more obtuse angle to cut the wire edge off. That might work.
 
planza:

Sounded pretty good but didnt work. Just pushed the edge over like previously. Thanks though.

BTW I am sharpening using the 20 degrees...although I have no idea how close to 20 degrees it is. It was slightly more obtuse than the factory edge.

I have read multiple sharpening articles and while I understand the theory, its not always easy to reproduce so any tips are greatly appreciated!
 
It can be a problem with high wear steels unless they are very hard. Try elevating the angle significantly as in 30/35 degrees. If this doesn't work the edge may be too deformed from all the flopping around and you need to cut it off directly by cutting lightly into the stone and then resetting. In general stropping doesn't tend to be productive on such high wear steels which heavy burrs, though I have not tried any of the very aggressive pastes like diamond or boron carbide. What happens on chromium/aluminum oxide is that the edge cracks off, goes completely dull and then slowly starts to recover. You might have more success with wider stones, especially waterstones which tend to work well on really heavy burr steels.

-Cliff
 
Using a fine (but not ultra-fine) stone, hone very lightly single strokes at 45 degrees. Do a single stroke on the right side then a single stroke on the left side. Use virtually no pressure. Alternate left-side/right-side single strokes. Do this for a total of 3 to 5 strokes on each side total.

After you get rid of your wire edge go back to your 20 degrees and do about 15 honing strokes per side (alternating left/right every stroke). Use light pressure. This shouldn't create a new wire edge and will restore the 20-degree edge you compromised by deburring at 45 degrees.
 
I generally get it off with a long stroke down the length of a fine stone by drawing the knife from heel to top over the stone rather than in the usual sharpening direction. BG-42 and stubborn stainless may require raising the angle a few degrees. For really really stubborn burrs, I raise it to 90 degrees and do a light slicing stroke (not sharpening, but heel to tip) on the edge itself (90 degrees to the stone on say an 8000 grit with light pressure... yes it does square off the edge, but it is still pretty fine) to get rid of the mushy steel and then reshape the edge again on a slightly coarser stone (say 5000).
 
Cliff,
I usually utilize a honing sequence that doesn't produce a lot of burr and I frequently don't do a specific deburring step. If I am just touching up one of my kitchen knives or an EDC I usually just use my Sharpmaker. I hone on alternate sides of the blade at my usual 10 degrees per side. I work up to the flats of the fine rods at that angle. I usually do about 8 strokes per side per grit. I use progressively lighter pressure as I procede. My final honing is a few very light strokes at 12 or 15 degrees per side. This isn't so much intended as a deburring step (though it has some of that effect) as it is intended to compensate for edge flex or irregularities. It insures that I got all the way to the edge everywhere along the blade.

In cases where I have removed a large amount of material from the edge I try and minimize my burr before I get to manual honing and I go through explicit deburring steps. About 2 weeks ago I sharpened about 50 kitchen knives prior to going to the soup kitchen. Doing that within 2 or 3 hours requires a streamlined approach, but some of the knives have a tough alloy and/or have been abused. I used my 4"x36" belt sander for most of the work. I started with a worn 80 grit belt for the worst blades. I always grind edge-first to try and transfer heat into the thicker part of the blade rather than back to the edge. For gross material removal on the damaged blades I work a lot on the area of the belt that is supported by the platten. I keep with the coarser grit until I basically have an edge. This produces a significant burr even when I finish grinding alternate sides. To reduce this and to smooth the edge profile I do a few passes on the unsupported section of the sander. This region has about a 2 inch span from the roller contact to the platten. It doesn't create much of a convexing, but it does have a little. It reduces the burr, but does not eliminate it.

I then did a few cycles of honing these blades on my worn 120 grit belts. This was done using the unsupported section of the belt. I brought in all of my less damaged blades and honed them to a greater or lesser degree on the 120 grit belt (depending on the amount of sharpening required and the abrasion resistance of the alloy). I moved onto my 220 grit belt then to my 400 grit belt. With the 400 grit belt I superelevated my honing from around 10 degrees to about 20 degrees and did a couple very light deburring passes. Then I lowered my angle back to my usual 10 degrees and did a few more light sharpening/polishing passes. Since I was using the unsupported section of my belt I figured that the final honing angle was somewhere between 10 and 15 degrees at the apex of the edge.

I moved onto manual at this point. I took the knives to my 12-inch extra-fine diamond bench hone. This is a smooth surfaced old Eze-Lap. I superelevated my honing angle to about 30 degrees per side. I very lightly honed edge-forwards alternating sides for about 3 strokes per side (more strokes for longer blades or blades that didn't feel the same when I honed opposite sides). This is my most explicit deburring step. Since this is done without an angle guide I was free to tweak my technique if it looked or felt like I had a special burr problem. I was in such a hurry that frankly I didn't care if every trace of burr was removed from every blade. This was just a quick way to handle the majority of the blades. I finished the knives by a modest amount of light honing strokes (5 or 10 strokes per side, alternating sides every stroke) on the flats of the medium rods of my Sharpmaker, with the rods set in the 30-degree (15 degrees per side) slots in the base. I didn't bother going to the finer rods. Most of the knives could shave to some degree and it was 12:30 AM by this time.

Since I used what I considered rather clean cutting abrasives (a 400-grit silicon carbide belt running edge-first and a diamond hone) I expected to get rid of my burrs at 30 degrees almost no matter what the blade alloy. If I was using only ceramic hones for my deburring I would have gone to a higher angle (rightly or wrongly). I usually work by sight and feel when I am sharpening just one or two knives. In that case I only go to the 45 degree angle if I find that I don't get rid of my burr at 30 degrees. I push the 45 degree angle as sort of an ultimate solution when someone has a burr that just doesn't seem to be responding. Even if their estimate of 45 degrees is wildly off and their technique is bad it will get rid of their burr. There are frequently other problems with their technique, but this will at least take the burr out of the picture.

PS. I had an expert critique my edges the next morning. Sigmund, the executive chef from our local grand hotel, volunteered to help us prepare lunch at the soup kitchen. He used one of my old 9-inch MAC CK-90 carving knives for all his work. He thought that it performed very well on the cutting board.
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Thanks for the replies guys!

I had a few minutes and first tried Jeff's method. I applied very little pressure and again it just moved the burr. I should have tried more pressure but I went on to Cliff's approach and this more aggressive action seemed to remove it for the most part. I did some honing at 20 deg and it will shave ok but not as sharp as I like it and not nearly hair popping sharp. I will spend some more time on it later this evening when I get home.

This is the first time doing much sharpening on S30V and it seems like quite a pain. 440C seems much easier.

I'll let yall know the final results but it looks like I finally got rid of the rascal.

Thanks!

Ryan
 
If your Lansky setup doesn't have the diamond hones, get'em! makes a big difference when reprofiling S30V. Actually makes it easy to get a scary sharp edge fast. Take your time and be thorough; don't progress to the next stone until already sharp with current stone. Good luck! :D
 
S30V has a higher wear resistance for sure. I Waved an S30V blade not long back for a guy and I was like to think I'd never get that thing finished. Its lots of hard grinding to get one where you want it out of that steel if you ask me. Not even in the same league as 440C for effort really.

I haven't read a lot of reports of this steel having a lot of burr problems though. I'm sure they are there but I just missed them I guess.

The burr is one of the things I really hate. I feel for you. On some of the ones I've run across that were really tough I sliced into bars of white or green rouge repeatedly until it was gone and then resharpened. Sometimes that worked sometimes it didn't and it took repeat tries. One thing I've noticed with my own collection is this though. Some knives are just burr creating knives. I've had some that were the same model, made the same time, and of the same steel and one just gets a burr while the other doesn't. Seems to me that once you realize you've got one that is prone to it thats just how it is. Maybe these other guys will disagree with that but its been my experience. Certain of my collection I can just tell you they are going to get a burr and be a PITA when it comes time to sharpen.

STR
 
I got into a 'chase the burr' cycle with the ATS34 blade on a Buck/Strider Tarani folder. I ground a 20 degree included angle main bevel, and the burr that formed seemed impossible to remove. I was beginning to question the heat treat of the blade, since the burr behavior seemed like a 400-series soft blade. I finally got rid of the burr with a micro-bevel of about 30 degrees included. It behaves very well with the 20/30 bevel combo.

My other premium-steel blades (440V, S30V and VG10) seem to perform best with a 20/25 bevel combo.

Is this common for ATS34, or do you think this ATS34 blade may be a bit soft?
 
yuzuha said:
I generally get it off with a long stroke down the length of a fine stone by drawing the knife from heel to top over the stone rather than in the usual sharpening direction. BG-42 and stubborn stainless may require raising the angle a few degrees. For really really stubborn burrs, I raise it to 90 degrees and do a light slicing stroke (not sharpening, but heel to tip) on the edge itself (90 degrees to the stone on say an 8000 grit with light pressure... yes it does square off the edge, but it is still pretty fine) to get rid of the mushy steel and then reshape the edge again on a slightly coarser stone (say 5000).

I learned this same tip from the guy that sells the Shapton stones in the U.S.... it's an excellent method.

cbw
 
Seems to me that burrs and ATS34 are frequently mentioned together. I've had more problems with that steel and some 154CM than any of the others. Even some D2 steel has been problematic for burr forming on occasion for me. The D2 from Knives of Alaska was really bad for that. I always assumed it was because they don't heat treat it to the optimal Rc that it should be at but who knows. Most D2 is 60 62 Rc and as I recall the Knives of Alaska blades I had were 58 Rc. I have come to the conclusion that softer does seem to bring on burrs easier just from the experience with these D2 blades so you may be right.

STR
 
I'm not sure I quite understand the 'heel to top'. What is the heel and what is the top? Are you saying instead of pulling the edge towards you down the stone to drag it away from you?

yuzuha said:
I generally get it off with a long stroke down the length of a fine stone by drawing the knife from heel to top over the stone rather than in the usual sharpening direction. BG-42 and stubborn stainless may require raising the angle a few degrees. For really really stubborn burrs, I raise it to 90 degrees and do a light slicing stroke (not sharpening, but heel to tip) on the edge itself (90 degrees to the stone on say an 8000 grit with light pressure... yes it does square off the edge, but it is still pretty fine) to get rid of the mushy steel and then reshape the edge again on a slightly coarser stone (say 5000).
Also, on the lansky sharpener how do most of you bring the stone in contact with the blade? Do you push the stone onto to blade like you were trying to push cut the stone? Do you pull it off the blade like you were stropping? Or do you run the stone along the length of the edge and move the stone from left to right more like a slicing cut? Just curious of others techniques.

Thanks again!

PS I have been very busy and still havent had a break to try and sharpen the knife again. Upon further examination there is a veeeery small burr in two places along the blade still. I will report back with what happens!
 
FlaMtnBkr said:
I'm not sure I quite understand the 'heel to top'. What is the heel and what is the top? Are you saying instead of pulling the edge towards you down the stone to drag it away from you?

It means I can't type worth a crap and should read "heel to tip" along the length of the edge from handle to point (not edge leading, nor edge trailing, but sideways, like scraping paint off a stir-stick back into the can)
 
To remove a burr with a stone you want to hone exclusively like you are trying to shave the stone. This could be called edge-leading. The opposite would be called edge-trailing or stropping. To minimize burr formation use edge-leading. If you use a system where you move a small stone and the blade is stationary you need to do the equivalent, have the stone run towards the edge first and progress back towards the bulk of the blade.

One of the reasons that your edge does not shave well is your 20 degree honing angle. When I want a blade to shave I grind the edge down to about 10 degrees and then put on a small final bevel at around 12 degrees. With my hair I never get good shaving ability with the final edge micro-bevel above 15 degrees.
 
Jeff Clark said:
For gross material removal on the damaged blades I work a lot on the area of the belt that is supported by the platten. I keep with the coarser grit until I basically have an edge. This produces a significant burr even when I finish grinding alternate sides. To reduce this and to smooth the edge profile I do a few passes on the unsupported section of the sander. This region has about a 2 inch span from the roller contact to the platten. It doesn't create much of a convexing, but it does have a little. It reduces the burr, but does not eliminate it.

I do similar, but mainly because my flat grinding on the platen tends to be sloppy and produce multiple bevels and the unsupported part will just blend them all together.

I moved onto manual at this point.

Have you tried finer belts and/or a buffer?

I didn't bother going to the finer rods.

Are all the knives large slicers?

FlaMtnBkr said:
This is the first time doing much sharpening on S30V and it seems like quite a pain. 440C seems much easier.

S30V has a low grindability and this makes it pretty sensitive to edge geometry. Wilson's S30V is fairly easy to sharpen, among the easiest I have seen (for stainless), but his edges are typically 0.005" or so thick and <15 degrees per side so there is little to no metal to be removed and the steel is very hard 60+ HRC so it tends to form crisp.

STR said:
S30V has a higher wear resistance for sure.

Lower grindability, but this isn't usually the critical issue in burr formation. M2 has a decent wear resistance but it tends to sharpen very well.

I haven't read a lot of reports of this steel having a lot of burr problems though.

When it first came out there were a number of problems reported with sharpening, generally not with burr removal just getting an edge in the first place as the grindability is so low compared to the other common cutlery stainless. Just scan through the 440C vs S30V page of Crucible and see if this is mentioned as a drawback :

http://www.crucibleservice.com/datash/S30Vvs440C3.pdf

Of course they are selling it so you don't expect them to promote its drawbacks strongly. Note down at the bottom there is even a blurb about ease of resharpening due to superior grindability which could easily lead someone to think this holds for the steels being compared there but this in general refers to steels of similar alloy composition comparing CPM to traditional ingot steels.

-Cliff
 
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