Deburring Chisel VG-10

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malaverdiere

Joined
Oct 3, 2016
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So this is my undaunted foe - a Japanese chisel-ground VG-10 petty knife.

I've tried with both my Lansky and my EdgePro-wannabe systems and I just couldn't get it decently sharp again. I'm following the deburring steps that many on the forum use though. Is the the chisel edge affecting things significantly?

I've tried this and still had burr laughing at me.
  1. Sharpen the only edge at ~10 degrees with a coarse stone, then medium, until a 1000 grit stone
  2. Used the finest stone at a few degrees on the flat side a few light strokes
  3. Slid edge through wood a few times
  4. Strop on plain leather

I tried a variant
  1. Sharpen the only edge at ~10 degrees with a coarse stone, then used the same stone at a few degrees on the flat side a few light strokes
  2. Repeat with a finer stone until reaching 1000 grit stone
  3. Slide edge through wood a few times and strop on plain leather
  4. Repeat until fed up

And I still had some burr reflecting back at me (but not as much). And I got a bunch of scratches on the flat side as a bonus :grumpy:

John from from Japanese Knife Imports mentioned micro-bevels as the way that the Japanese get rid of the burr. Is that the best/only way?
What about a compound on the strop? Or deburring on those grooved ceramic rods?
 
On chisel ground I like to use the fine stone or whatever stone I plan on finishing with on the flat side. I'll do this every so often as I work the ground side to keep the burr from getting too big to begin with, as I run up through a progression.

Once I'm hitting the ground side with the same finisher stone, I'll backdrag the burr on some wood or plastic from the flat side toward the ground side to make it stand up taller - pressure should be light, especially with a real thin grind.

Then work the burr off with some leading passes on the ground side at a slightly larger angle. If you don't want a microbevel, stop often and check the burr to see when its 90% gone, then drop back down to the original, more acute angle.

I'll use a loaded strop of sorts on the ground side (paper over a stone or Washboard), but keep it to a minimum on the flat side - you don't want to round or otherwise alter the flat side geometry.

Some folks will apply a microbevel to the ground side or both sides. I normally only sharpen woodworking blades with chisel grind and I don't want any microbevel on the down side.

The angles you are working are very acute, and VG10 is known for holding onto stubborn burrs, so the shallow angle won't be helping.

If dragging the edge through wood to help with burr removal, do it every few passes on the stone - grind, grind, grind, drag through wood, grind, grind, grind, drag etc. Don't wait till you get to the end or it will have very little effect on any but the smallest of burrs. Same use of the polishing stone for the flat side - every few passes flip the blade and hit the flat, back to the grind...
 
10 degrees on just one side means you have a 10 degree inclusive edge bevel. Good Japanese knives will rarely hold a 10 degree Per Side bevel so 10 degrees on just one side is simply asking for failure.

Next, VG-10 holds a burr and can be a real pain to remove. It will require more strokes than normal on a finishing stone in order to reduce the burr enough that stropping will actually do something.

Lastly, it's probably a 70/30 type bevel. Basically, you sharpen at the same angle on each side except you sharpen on the beveled side of the blade much more, only moving to the backside to maintain bevel geometry and to keep the burr minimized. It's actually a very simple form of sharpening that will result in a high degree of sharpness and cutting ability... when done correctly.
 
Jason B. said:
10 degrees on just one side means you have a 10 degree inclusive edge bevel. Good Japanese knives will rarely hold a 10 degree Per Side bevel so 10 degrees on just one side is simply asking for failure.

Next, VG-10 holds a burr and can be a real pain to remove. It will require more strokes than normal on a finishing stone in order to reduce the burr enough that stropping will actually do something.

Lastly, it's probably a 70/30 type bevel. Basically, you sharpen at the same angle on each side except you sharpen on the beveled side of the blade much more, only moving to the backside to maintain bevel geometry and to keep the burr minimized. It's actually a very simple form of sharpening that will result in a high degree of sharpness and cutting ability... when done correctly.
Click to expand...

Thanks for your comments on the 10 degrees. I was under the impression that those stronger steels were able to handle such thinness. I'll definitely micro-bevel then. (Or will that even not be enough?)
What works good in the kitchen in general?

The factory edge came with no visible edge on the flat side, so I'm very confident about that blade geometry. I don't mind changing it, but I'd rather avoid that.
 
HeavyHanded said:
On chisel ground I like to use the fine stone or whatever stone I plan on finishing with on the flat side. I'll do this every so often as I work the ground side to keep the burr from getting too big to begin with, as I run up through a progression.

Once I'm hitting the ground side with the same finisher stone, I'll backdrag the burr on some wood or plastic from the flat side toward the ground side to make it stand up taller - pressure should be light, especially with a real thin grind.

Then work the burr off with some leading passes on the ground side at a slightly larger angle. If you don't want a microbevel, stop often and check the burr to see when its 90% gone, then drop back down to the original, more acute angle.

I'll use a loaded strop of sorts on the ground side (paper over a stone or Washboard), but keep it to a minimum on the flat side - you don't want to round or otherwise alter the flat side geometry.

Some folks will apply a microbevel to the ground side or both sides. I normally only sharpen woodworking blades with chisel grind and I don't want any microbevel on the down side.

The angles you are working are very acute, and VG10 is known for holding onto stubborn burrs, so the shallow angle won't be helping.

If dragging the edge through wood to help with burr removal, do it every few passes on the stone - grind, grind, grind, drag through wood, grind, grind, grind, drag etc. Don't wait till you get to the end or it will have very little effect on any but the smallest of burrs. Same use of the polishing stone for the flat side - every few passes flip the blade and hit the flat, back to the grind...
Click to expand...

In short, do what I've been doing, but more maniacally and agressively? ;)

The only thing I didn't get was the backdragging part. Is that a stropping motion with a big angle?
 
malaverdiere said:
So this is my undaunted foe - a Japanese chisel-ground VG-10 petty knife.

I've tried with both my Lansky and my EdgePro-wannabe systems and I just couldn't get it decently sharp again. I'm following the deburring steps that many on the forum use though. Is the the chisel edge affecting things significantly?

I've tried this and still had burr laughing at me.
  1. Sharpen the only edge at ~10 degrees with a coarse stone, then medium, until a 1000 grit stone
  2. Used the finest stone at a few degrees on the flat side a few light strokes
  3. Slid edge through wood a few times
  4. Strop on plain leather

I tried a variant
  1. Sharpen the only edge at ~10 degrees with a coarse stone, then used the same stone at a few degrees on the flat side a few light strokes
  2. Repeat with a finer stone until reaching 1000 grit stone
  3. Slide edge through wood a few times and strop on plain leather
  4. Repeat until fed up

And I still had some burr reflecting back at me (but not as much). And I got a bunch of scratches on the flat side as a bonus :grumpy:

John from from Japanese Knife Imports mentioned micro-bevels as the way that the Japanese get rid of the burr. Is that the best/only way?
What about a compound on the strop? Or deburring on those grooved ceramic rods?
Click to expand...

Aside from the aspects covered by Jason and Martin (HeavyHanded), I'll just offer that a hard-backed denim strop with some aluminum oxide compound ('white rouge', Flitz, Simichrome, Mother's Mag polish, etc) has served me very, very well in deburring VG-10. Dragging through wood and stropping on bare leather has never worked for me, in removing the tenacious burrs on this steel.

I'd also avoid (like the plague) using a ceramic rod of any kind to attempt deburring of VG-10; unless it's used with an expertly light and perfect touch, it's likely only to make the burring issues worse (focused pressure on very narrow contact area, and on a very hard media like ceramic, is a perfect storm for burr creation).


David
 
malaverdiere said:
In short, do what I've been doing, but more maniacally and agressively? ;)

The only thing I didn't get was the backdragging part. Is that a stropping motion with a big angle?
Click to expand...

Yes, like at 90° or so.

Realistically you need to open that angle up a bit - most straight razors aren't even honed to 10° inclusive. At 10° you can't even drag the edge across wood and hope to get a good outcome - if the edge flexes at all its going to fold and for all intents and purposes it'll turn into a burr.

I'd think 20-22 would be closer to realistic, maybe even closer to 24-26°. A fat microbevel/new cutting bevel at a wider angle, some aggressive stropping.
 
malaverdiere said:
So this is my undaunted foe - a Japanese chisel-ground VG-10 petty knife.

I've tried with both my Lansky and my EdgePro-wannabe systems and I just couldn't get it decently sharp again. I'm following the deburring steps that many on the forum use though. Is the the chisel edge affecting things significantly?

I've tried this and still had burr laughing at me.
  1. Sharpen the only edge at ~10 degrees with a coarse stone, then medium, until a 1000 grit stone
  2. Used the finest stone at a few degrees on the flat side a few light strokes
  3. Slid edge through wood a few times
  4. Strop on plain leather

I tried a variant
  1. Sharpen the only edge at ~10 degrees with a coarse stone, then used the same stone at a few degrees on the flat side a few light strokes
  2. Repeat with a finer stone until reaching 1000 grit stone
  3. Slide edge through wood a few times and strop on plain leather
  4. Repeat until fed up

And I still had some burr reflecting back at me (but not as much). And I got a bunch of scratches on the flat side as a bonus :grumpy:

John from from Japanese Knife Imports mentioned micro-bevels as the way that the Japanese get rid of the burr. Is that the best/only way?
What about a compound on the strop? Or deburring on those grooved ceramic rods?
Click to expand...

for what its worth, what i said was that microbevels are just one way (of many) that japanese craftsmen and knife sharpeners get rid of burrs. They arent always the best, but for the things they are well suited for, they work extremely well. Stropping is absolutely another way, both on stones and on stropping substrates. Cutting through dense materials is another way. Sometimes, a multitude of ways working together is best. It will depend on the knife, steel, heat treatment, sharpening method, how large of a burr was formed, your skill, etc.
 
Chris "Anagarika";16627645 said:
I'm curious. Is the 10° on sharpening side original angle from factory?
Click to expand...

I'm not sure what the factory was.
I tried matching it with the Lansky system in the 17 degrees slot and adjusting the depth of the rod with the sharpie trick (but I'm not sure I did a good job at it). I used an app on my phone to measure the angle, but I couldn't really get the thing level - so I was guessing that the original angle was in the 10-15 degrees range. (I know - not helpful).

I was trying to find typical edge angles, and there is nothing clearer than 'at least 15 degrees, often more' The knife connection mentions 20-30 degrees.

Connecting the dots, I must have significantly messed up measuring the angle, or I missed a micro bevel on the other side "The backside features a practically invisible 15º microfacet to create a balanced cutting edge."
 
Thanks. I guess it's moot point right now.
Identity of the said knife will allow some resident experts like Jason and Martin providing guidance on what's optimum.
 
As you are seeing this is an Asymmeteric ground and beveled knife. This is NOT a chisel edge and should not be sharpened like one.

The blade itself is likely Convex on the presentation side while being completely flat on the backside. When sharpened correctly the blade will have unmatched sharpness and cutting ability when compared to 50/50 edge bevels. Or at least that's the opinion.

You don't really sharpen at different angles on each side but you just grind more on one side than the other. The 70/30 or 80/20 designation is more of a percentage of how much you should sharpen on each side.
 
So I faced the beast again with mixed success.

Remember, I previously made it into a chisel profile at 10 degrees.

I set up on my Lansky sytem and measured the angles. The 17 degrees slot ended up at 10, and the 25 degrees slot was measuring 15. The 30 degrees slot was measuring 21 or so.

So since I wouldn't be able to give myself a 25 degrees chisel, I decided to do a 15 degrees grind on both sides, like Jason B. said. The scratching on each side was in a ratio of about 4:1 (not that I counted).
I started on the coarse (red - 120 grit) stone and made sure I felt burr after each side and went through the usual medium-fine-extra fine progression. Before switching to the next stone, I did stropping motions with light pressure on each side and drove the edge gently through wood to deburr. I could still feel some left, but I continued.

After finishing with the 1000 grit stone the same way, I stropped on leather with green compound.
At first, I went for the aesthetics - I went flat on the flat side and then 10 degrees on the ground side, to some scratches and embellishing the previous 10 degrees grind that looked scratchy. Then I increased angle to roughly 15 degrees. I could still feel some tiny burr, so I increased the angle some more (maybe 20 degrees) and I got rid of it.

The end result is definitely burr-free, but not really sharp. It passes the paper test, but won't cut hair at all. By the way, I tried to cut hair on my arm after the 600 and the 1000 stone and that didn't work either, so it is not the stropping that ruined everything.

In hindsight, I realise that I have levelled my reading on the non-flat side of the knife, so probably all those angle readings are bogus (but consistently so).
Any other mistakes you can spot?
 
I still use it to remove stubborn burr/wire-edge. Maybe worth a try...

[video=youtube_share;l2ynSDYEUYI]http://youtu.be/l2ynSDYEUYI[/video]
 
Sounds like you didn't grind the edge to an apex. If you can't slice paper or shave off of your coarsest stone then there is no readon to continue on with finer stones, only polishing surface scratches at that point.
 
Jason B. said:
Sounds like you didn't grind the edge to an apex. If you can't slice paper or shave off of your coarsest stone then there is no readon to continue on with finer stones, only polishing surface scratches at that point.
Click to expand...

I just got my mind blown. I thought that shaving hair off my arm wouldn't happen below 600 grit somehow. I can't remember where I got this silly idea from.
Do I need to deburr aggressively first, or this is going to work even if some burr is left?

Do you have other tests after coarse stones to tell 'your apex is ready'? Catching on the nail?

P.S. So the burr I felt would've been from the previous sharpening? Or burr occurs even if not fully apexed? (I think I saw that in another thread - but my memory sucks - sorry for asking again)
 
bluntcut said:
I still use it to remove stubborn burr/wire-edge. Maybe worth a try...

[video=youtube_share;l2ynSDYEUYI]http://youtu.be/l2ynSDYEUYI[/video]
Click to expand...

So you push the burr with a stick and then grind in an edge-leading manner. Isn't that motion good at generating more burr? I observed a lot of videos with people doing edge-trailing strokes for deburring.
 
Yes, fold & cut off the burr with edge lead. Give it a try, since you already tried edge trailing...
malaverdiere said:
So you push the burr with a stick and then grind in an edge-leading manner. Isn't that motion good at generating more burr? I observed a lot of videos with people doing edge-trailing strokes for deburring.
Click to expand...
 
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