soatoz
12th April 2007, 06:00 PM
How to Sharpen a Plane Blade Part 3: How to sharpen the front side freehanded (High level sharpening).
This article is for intermediate sharpeners who are familiar with basic sharpening. Please refer to Part 1 if you are not sure about the basics. I will explain how to sharpen the blade to level c from my sharpening skill classification. Please refer to “On Japanese sharpening stones, saws, and some ads(?)” (scroll down a bit.) article for my classification of sharpening skill.
1.
My hand sharpening starts after the angle of the bevel has been fixed using a honing guide. As I have written in the classification article, the bevel is not perfectly flat using a honing guide, thus we first flatten the slightly rounded bevel, using a med grit synthetic stone. Shapton ("Ha no Kuromaku (Power behind the blade)" Basically not sold outside Japan. Japanese equivalent stone to the super famous "Professional Series " sold in the US.), Bester, Sigma Power #1000 are my three highly recommended stones. All these I consider made with an alien technology:2tsup:
It is easier to keep the blade steady if you hold the blade as shown in Photo1 or 2. Photo2 is easier to maintain the flat, but you need to be careful that the stone is not concaved at all, because if it is even to a small extent, the bevel will be rounded to the width direction. So, I usually hold it in Photo1 style. A is my right hand’s index finger, B is left hand’s middle finger, and C medicine finger. You press B the hardest. This finger controls the overall pressure you want to apply to the blade. A and C pressing slightly lighter and control the pressure distribution to right and left. If your blade is skewed you fix it by pressing A or C more. We are talking about very delicate level of pressure though. The whole bevel is always touching, but the pressure applied is different.
http://www.geocities.com/soatoz/photos/PBsharp/Pbsharp1.JPG
Photo1
http://www.geocities.com/soatoz/photos/PBsharp/Pbsharp2.jpg
Photo2
In Photo1, see how the black mark (cut steel particle) on the stone is getting wider as I move towards the end of the stone. The bevel is very slightly rounded to the width direction from grinding on the prior stone Shapton #1000, so when I move to Bester #2000 shown here, only the centre of the blade touches the stone, and as I grind, the whole width touches the stone. You need to make sure, by checking the black mark, that the whole width is touching the stone before you move onto the next stone. In order to check the mark, the stone cannot be flooded with water. You need to feed the right amount of water, not too wet but not too dry.
You would start grinding off the center of the bevel as shown in Pic1 below, and as the steel part start to touch the stone you shift the pressure to the steel side a little as shown in Pic2 so that the iron and the steel gets ground off evenly. Both Photo 1 and 2 shows where I'm pressing closer to the tip of the blade (blue arrow "2" in Pic2), after the bevel is completely touching the stone. I sometimes go even closer to make sure that the tip is touching the stone and scrape my finger with the stone, so I have a callus formed on the tip of my fingers.
If you keep pressing the center of the bevel (red arrow "1" in Pic2), you’ll end up grinding the iron more than the steel, thereby lifting up the tip, keeping the very tip from touching the stone. This is the most common error made by majority of handsharpeners, so I advise the intermediate sharpeners to check the very tip of the blade with a microscope (x100 to x200) after you have sharpened to the max. All Kezurou-kai member check the tip with a microscope. If you have never checked the tip with a microscope, most of the time no matter how polished the bevel look, the tip has a rough serration. If the tip has touched the high quality natural final finishing stone, the tip should look like Photo 3. This is my Yokoyama blacksmith's Tougou Reigou steel polished up with my best Nakayama Asagi stone, checked by x200 micro scope. If you are interested in checking your tip, you can send me your blade and I'll take a photo and send the photo via email. Unfortunately I cannot return your blade especially when it's a good one!:D hahaha~~
Keep grinding until all the surface of the bevel looks “uniformly” marked by the med grit stone.
http://www.geocities.com/soatoz/photos/PBsharp/Tougou_x200.jpg
Photo 3
http://www.geocities.com/soatoz/photos/PBsharp/freehand.jpg
2.
Even though the mark looks uniform the bevel is still slightly rounded. This is because when you go back and forth, the friction causes the blade to rock a little. So what I do is before going into polishing phase, I make the bevel flat by sharpening by pushing only. By doing this there would be no rocking motion thereby the bevel becomes absolutely flat. You need to “feel” the whole surface of the bevel touching the stone. If it feels funny (this funny feeling is beyond my ability to express with words…), it is not absolutely flat. You'll KNOW if it is flat or not. If you are not certain, it is probably not flat. This step is the most important step to make the bevel absolutely flat.
3.
When you can feel that it is flat, do the same process with #2000, then move on to #4000~5000 or Aoto (Blue stone) or equivalent. From here on, you should consider as polishing rather than grinding. Of course you are still trying to sharpen the edge, but it is better to think you are trying to polish the whole bevel. That way, you won’t press too hard onto the stone. Pay attention to the harsh mark being erased by the finer stone. If you are using Aoto, the bevel especially the iron part will become more hazy and misty. Keep the pressure on the steel side of the blade without lifting the bevel edge side.
4.
Move on to natural med fine finishing stone, or #8000. Do the same process as step 3. Pay extra attention to erase all the mark especially on the tip of the blade, and make the whole bevel look evenly and finely marked. You might need to sacrifice a bit of your finger tip skin at this stage! The marks would become super thin hairlines if you are using #8000, and not visible (hazy) if you are using a natural stone. And you should be able to stick the blade onto the stone without holding the blade at all. If the blade doesn't stick, the bevel is probably not flat.
http://www.geocities.com/soatoz/photos/Photo_0001a_Sharpening1.jpg
5.
Now polish it up with the best and finest stone you have. Usually you need to apply as less pressure as you can, just enough for the polishing particles to polish up the bevel. Again pay extra attention to the tip of the blade.
If you are using good hard Suita stones for the finishing, never use Nagura stones to create the slurry, because coarse and hard particles of Nagura gets caught in the Su (the hole of Suita) and they will keep scratching the bevel. Also if you are using super hard stones such as hard Oozuku and Nakayama, again never use Nagura, because the particles of Nagura is coarser than these stones, they will scratch the bevel badly. But without any dressing, hard stones are unable to be used….
For these stones, you can either use a piece of the identical stone instead of Nagura, or... a super fine diamond stone. Without them, these super hard stones are unusable. Basically I recommend to stay away from these super hard (usually expensive) stones if you are a novice sharpeners, and get softer stones as a start until you can stick the blade to the stone.
Atoma brand is my most recommened diamond sharpener. Diamond stones are usually not absolutely flat and also very expensive, but Atoma brand is quite flat and not too expensive compared to other brands. I only have a couple with me, and they are going quickly, so if you are interested contact me.
6.
Take the burr off by polishing the front and the back alternatively couple of times, and we’re done!
This article is for intermediate sharpeners who are familiar with basic sharpening. Please refer to Part 1 if you are not sure about the basics. I will explain how to sharpen the blade to level c from my sharpening skill classification. Please refer to “On Japanese sharpening stones, saws, and some ads(?)” (scroll down a bit.) article for my classification of sharpening skill.
1.
My hand sharpening starts after the angle of the bevel has been fixed using a honing guide. As I have written in the classification article, the bevel is not perfectly flat using a honing guide, thus we first flatten the slightly rounded bevel, using a med grit synthetic stone. Shapton ("Ha no Kuromaku (Power behind the blade)" Basically not sold outside Japan. Japanese equivalent stone to the super famous "Professional Series " sold in the US.), Bester, Sigma Power #1000 are my three highly recommended stones. All these I consider made with an alien technology:2tsup:
It is easier to keep the blade steady if you hold the blade as shown in Photo1 or 2. Photo2 is easier to maintain the flat, but you need to be careful that the stone is not concaved at all, because if it is even to a small extent, the bevel will be rounded to the width direction. So, I usually hold it in Photo1 style. A is my right hand’s index finger, B is left hand’s middle finger, and C medicine finger. You press B the hardest. This finger controls the overall pressure you want to apply to the blade. A and C pressing slightly lighter and control the pressure distribution to right and left. If your blade is skewed you fix it by pressing A or C more. We are talking about very delicate level of pressure though. The whole bevel is always touching, but the pressure applied is different.
http://www.geocities.com/soatoz/photos/PBsharp/Pbsharp1.JPG
Photo1
http://www.geocities.com/soatoz/photos/PBsharp/Pbsharp2.jpg
Photo2
In Photo1, see how the black mark (cut steel particle) on the stone is getting wider as I move towards the end of the stone. The bevel is very slightly rounded to the width direction from grinding on the prior stone Shapton #1000, so when I move to Bester #2000 shown here, only the centre of the blade touches the stone, and as I grind, the whole width touches the stone. You need to make sure, by checking the black mark, that the whole width is touching the stone before you move onto the next stone. In order to check the mark, the stone cannot be flooded with water. You need to feed the right amount of water, not too wet but not too dry.
You would start grinding off the center of the bevel as shown in Pic1 below, and as the steel part start to touch the stone you shift the pressure to the steel side a little as shown in Pic2 so that the iron and the steel gets ground off evenly. Both Photo 1 and 2 shows where I'm pressing closer to the tip of the blade (blue arrow "2" in Pic2), after the bevel is completely touching the stone. I sometimes go even closer to make sure that the tip is touching the stone and scrape my finger with the stone, so I have a callus formed on the tip of my fingers.
If you keep pressing the center of the bevel (red arrow "1" in Pic2), you’ll end up grinding the iron more than the steel, thereby lifting up the tip, keeping the very tip from touching the stone. This is the most common error made by majority of handsharpeners, so I advise the intermediate sharpeners to check the very tip of the blade with a microscope (x100 to x200) after you have sharpened to the max. All Kezurou-kai member check the tip with a microscope. If you have never checked the tip with a microscope, most of the time no matter how polished the bevel look, the tip has a rough serration. If the tip has touched the high quality natural final finishing stone, the tip should look like Photo 3. This is my Yokoyama blacksmith's Tougou Reigou steel polished up with my best Nakayama Asagi stone, checked by x200 micro scope. If you are interested in checking your tip, you can send me your blade and I'll take a photo and send the photo via email. Unfortunately I cannot return your blade especially when it's a good one!:D hahaha~~
Keep grinding until all the surface of the bevel looks “uniformly” marked by the med grit stone.
http://www.geocities.com/soatoz/photos/PBsharp/Tougou_x200.jpg
Photo 3
http://www.geocities.com/soatoz/photos/PBsharp/freehand.jpg
2.
Even though the mark looks uniform the bevel is still slightly rounded. This is because when you go back and forth, the friction causes the blade to rock a little. So what I do is before going into polishing phase, I make the bevel flat by sharpening by pushing only. By doing this there would be no rocking motion thereby the bevel becomes absolutely flat. You need to “feel” the whole surface of the bevel touching the stone. If it feels funny (this funny feeling is beyond my ability to express with words…), it is not absolutely flat. You'll KNOW if it is flat or not. If you are not certain, it is probably not flat. This step is the most important step to make the bevel absolutely flat.
3.
When you can feel that it is flat, do the same process with #2000, then move on to #4000~5000 or Aoto (Blue stone) or equivalent. From here on, you should consider as polishing rather than grinding. Of course you are still trying to sharpen the edge, but it is better to think you are trying to polish the whole bevel. That way, you won’t press too hard onto the stone. Pay attention to the harsh mark being erased by the finer stone. If you are using Aoto, the bevel especially the iron part will become more hazy and misty. Keep the pressure on the steel side of the blade without lifting the bevel edge side.
4.
Move on to natural med fine finishing stone, or #8000. Do the same process as step 3. Pay extra attention to erase all the mark especially on the tip of the blade, and make the whole bevel look evenly and finely marked. You might need to sacrifice a bit of your finger tip skin at this stage! The marks would become super thin hairlines if you are using #8000, and not visible (hazy) if you are using a natural stone. And you should be able to stick the blade onto the stone without holding the blade at all. If the blade doesn't stick, the bevel is probably not flat.
http://www.geocities.com/soatoz/photos/Photo_0001a_Sharpening1.jpg
5.
Now polish it up with the best and finest stone you have. Usually you need to apply as less pressure as you can, just enough for the polishing particles to polish up the bevel. Again pay extra attention to the tip of the blade.
If you are using good hard Suita stones for the finishing, never use Nagura stones to create the slurry, because coarse and hard particles of Nagura gets caught in the Su (the hole of Suita) and they will keep scratching the bevel. Also if you are using super hard stones such as hard Oozuku and Nakayama, again never use Nagura, because the particles of Nagura is coarser than these stones, they will scratch the bevel badly. But without any dressing, hard stones are unable to be used….
For these stones, you can either use a piece of the identical stone instead of Nagura, or... a super fine diamond stone. Without them, these super hard stones are unusable. Basically I recommend to stay away from these super hard (usually expensive) stones if you are a novice sharpeners, and get softer stones as a start until you can stick the blade to the stone.
Atoma brand is my most recommened diamond sharpener. Diamond stones are usually not absolutely flat and also very expensive, but Atoma brand is quite flat and not too expensive compared to other brands. I only have a couple with me, and they are going quickly, so if you are interested contact me.
6.
Take the burr off by polishing the front and the back alternatively couple of times, and we’re done!