# Help please. Can't raise a burr on a carbon knife.



## rhymeswithoranj (Sep 8, 2015)

So, I have two Konosuke HH gyutos, which, after much practice, I can get pretty damn sharp on my Edge Pro (and I know the Edge Pro doesn't get much love here, but hey! Works for me). I've had great difficulty getting rid of persistent burrs/wire edges on them, but have slowly learnt to use strops/micro bevels and get sharp, long lived edges. 

So, I put my Teruyasu Fujiwara Nashiji Petty on the stones today.

And I cannot either raise a burr or get it sharp. I checked my angle with a magic marker. All good. I dropped down to the Edge Pro 220 grit. I figured I might just not be able to feel the burr, and went through a sharpening progression anyway. 

Nothing is working. I can't get it sharp. I'm assuming that I'm doing something wrong - because it is a super hard carbon, but it's killing me that I can't even put a halfway decent edge on it.

Your help and advice would be much appreciated.


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## Pensacola Tiger (Sep 8, 2015)

You are probably not getting to the very edge, and are merely thinning behind the edge without actually sharpening the blade. Regardless of what you see through a loupe when you use a marker, you should be raising a detectable burr with your coarsest stone. 

Try increasing the angle at least 5 to 10 degrees and making two or three passes with your 220 grit, then check for a burr. If you don't get one, increase the angle until you do. At that high an angle it shouldn't take more than a couple of passes to raise a burr. If you don't raise a burr, raise the angle until you do, don't keep grinding away. Then flip the knife and repeat.


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## rhymeswithoranj (Sep 8, 2015)

Pensacola Tiger said:


> You are probably not getting to the very edge, and are merely thinning behind the edge without actually sharpening the blade. Regardless of what you see through a loupe when you use a marker, you should be raising a detectable burr with your coarsest stone.
> 
> Try increasing the angle at least 5 to 10 degrees and making two or three passes with your 220 grit, then check for a burr. If you don't get one, increase the angle until you do. At that high an angle it shouldn't take more than a couple of passes to raise a burr. If you don't raise a burr, raise the angle until you do, don't keep grinding away. Then flip the knife and repeat.



Sure, that sounds likely. If so, could I just persist with the 220 at the current angle (15*) until I raise a burr? Pretty sure the steel can hold an edge at that angle.


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## Pensacola Tiger (Sep 8, 2015)

rhymeswithoranj said:


> Sure, that sounds likely. If so, could I just persist with the 220 at the current angle (15*) until I raise a burr? Pretty sure the steel can hold an edge at that angle.



Yes, you could, but with a knife as thin as a petty I'd want to leave some metal behind the edge for strength. What you are doing by raising the angle is putting a microbevel on the edge, which is often all the sharpening a thin knife needs, at least for a while. You can always lower the angle later, if you want.


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## rhymeswithoranj (Sep 8, 2015)

Pensacola Tiger said:


> Yes, you could, but with a knife as thin as a petty I'd want to leave some metal behind the edge for strength. What you are doing by raising the angle is putting a microbevel on the edge, which is often all the sharpening a thin knife needs, at least for a while. You can always lower the angle later, if you want.



Ok. Thank you. Does that apply in this case though? The Teruyasu Fujiwaras are thin behind the edge, but they are not anything like as thin as the Konosukes.


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## Pensacola Tiger (Sep 8, 2015)

rhymeswithoranj said:


> Ok. Thank you. Does that apply in this case though? The Teruyasu Fujiwaras are thin behind the edge, but they are not anything like as thin as the Konosukes.



It would depend on the geometry of the knife, which is hard to assess by looking at the spine (Shigefusa knives are an example). Raise the burr first, then find out how it cuts to see if you need to lower the angle.


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## rhymeswithoranj (Sep 8, 2015)

Right. So I've been grinding away with the 220 at 20* for the last 15 minutes. Zero burr action. Surely the edge can't be greater than 20*?


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## Pensacola Tiger (Sep 8, 2015)

rhymeswithoranj said:


> Right. So I've been grinding away with the 220 at 20* for the last 15 minutes. Zero burr action. Surely the edge can't be greater than 20*?



Was the knife sharp when you got it?


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## krx927 (Sep 8, 2015)

I had similar issue with EdgePro and Moritako Hamono knife. I could get a burr on the first side but on the opposite side (one part about 1/3 from heel) I was grinding for 20 mins before I got small burr!? The end result was that I raised the edge of the knife in that spot (ruined the profile) that I needed to fix later.
What I was also getting was microchipping on the knife using original EP stones. 

I never figured it out why I couldn't raise a burr :scratchhead: For the microchipping I suspect the crappy EP stones were causing it.

After that I sold the Moritaka, bought some nice stones (Choseras and some other) and never used EdgePro again  Anybody wants to buy it


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## Mrmnms (Sep 8, 2015)

How bout some pictures of the knife. It's hard to imagine that knife was originally anything like 20 degrees per side. A burr is a burr, whether free hand , Edgepro or belt. Yours stones are flat, clean?


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## daveb (Sep 8, 2015)

From what you've described you should have a burr like a shelf on the side of the blade.


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## Jaspernowhere (Sep 9, 2015)

Honestly, this is why freehand sharpening is recommended. You learn to use your ears more than your eyes, listen to the process. It will tell a story that a jig system can't. You have tactile feedback when free handing. Edge pro is a crutch that always causes problems that can't be answered by the user, whereas a simple knife on stone speaks volumes. It tells you everything you need to know if you just listen and feel.


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## Pensacola Tiger (Sep 9, 2015)

rhymeswithoranj said:


> Right. So I've been grinding away with the 220 at 20* for the last 15 minutes. Zero burr action. Surely the edge can't be greater than 20*?



Did you ever raise a burr?


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## kohtachi (Sep 9, 2015)

Angle is more acute then the original angle, your rocking the blade, or your stones are not flat, would be my guess.


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## Ruso (Sep 10, 2015)

rhymeswithoranj said:


> Right. So I've been grinding away with the 220 at 20* for the last 15 minutes. Zero burr action. Surely the edge can't be greater than 20*?


You have probably ground the half of petty off by now.


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## XooMG (Sep 10, 2015)

Just a silly idea, but consider switching to a higher grit stone (500-1000 range) and sharpen for 30 seconds with moderate pressure, with the marker test just to be sure.


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## rhymeswithoranj (Sep 12, 2015)

Ok. So sorry for my late response - I've been following, but have been busy with three kids and a kitchen renovation (oh the pain...). 

So, I took a step back, and a deep breath, and worked through a few things, bearing in mind the suggestions in this thread - thank you for your help.

First, I wasn't grinding at 20* - I'd misremembered the Edge Pro scale, and it was a lot shallower. 

So, I basically went to a higher grit, and took my time, and really paid attention. Felt like the knife was getting sharper using the 400 at 18*. But not raising a burr. So it lifted to 20. Started to feel a burr - but much, much smaller than I get with the Konosukes. Still, followed through. Kept going until I was pretty sure I had raised a burr on both sides - harder for me to tell, being used to the really obvious burr I get on the other, stainless knives. Went up through the stones at the same angle. Seemed to be really easy to get rid of this almost undertake burr. And, finishing off with very light strokes with the Edge Pro 1000 grit has given me a sharp, yet still seemingly toothy edge. Which is easily the equal of the Konosukes, far as I can tell. 

So, looks like I've learnt a few things. Don't guess about the bevel angles. Understand the feedback you get from the stones. And, maybe, carbon is actually way easier to sharpen than stainless - cos even though I had mucho trouble at first, and I'm still not 100% convinced I raised a burr, as it was so hard to tell, the difference in chasing and getting rid of the burr is enormous. I've used all sorts of tricks and techniques with the Konusuke HHs. The carbon seems much, much easier to de burr.


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## BHolcombe (Sep 12, 2015)

On a coarse grit with carbon steel I would still expect to feel a pretty decent burr, but at 1000 grit I think a noticeable and consistent burr is good. I would expect a less noticeable burr than on stainless.


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