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View Full Version : Sharpening Japanese Chisels; did I screw up?



Luke Dupont
06-05-2016, 7:09 PM
I ordered an inexpensive set of Japanese chisels to give a try, just to see if I liked them. These, specifically: http://www.amazon.com/dp/B004GBKYN2/ref=sr_ph?ie=UTF8&qid=1465167459&sr=1&keywords=Japanese+chisel

I got them, and after setting the hoops, went to sharpening, and I noticed that it was extremely difficult to lap the back. I started with the 1" chisel, and I couldn't get the last half inch towards the cutting edge in line with the rest of the back. I think I got it down to about 3/16" from the edge, after more than an hour of work on my diamond stone.

Then I realized, looking at the other chisels, that they too have the first 1/2" or so on a different plane from the rest of the back. This makes me wonder; am I supposed to leave them this way, and not lap them dead flat as one would do with western chisels? What, then, is the purpose of the hollow found in Japanese chisels?

Also, what should I do with my chisel that I've half-lapped? It nolonger has a large enough reference surface to sharpen only the tip with, but it also is still quite out from dead flat, meaning I can't just place it flat on the stone to sharpen with -- so, I effectively have the worst of both worlds. I am starting to wear away the hollow in the middle, which I know is not ideal. Should I try to re-establish that secondary flat which was originally there, or just commit to a dead flat back and spend a few more hours grinding?

Also, uh, is it some terrible, taboo practice to sharpen Japanese chisels with a convex bevel? This is how I sharpen my western chisels and planes, and what I've done already on my 1" chisel; I tend to prefer this method, and the resulting geometry. However, I've noticed that most Japanese craftsmen seem to keep a flat bevel and use that as a guide when sharpening, which is why I ask.

This is why I didn't buy expensive Japanese chisels right off the bat :D

Reinis Kanders
06-05-2016, 7:28 PM
Sounds like a mess:( Upload some pictures, otherwise it is hard to judge.

Patrick Chase
06-05-2016, 7:42 PM
You should always totally grind out the concavity on the back and thereby make them dead flat, like the state of Kansas. Doing so will get you maximum style points from every Japanese tool connoisseur who ever sees your handiwork.

[yes, that was sarcasm. No, you shouldn't do that, though what you're asking about is more of a grey area and usually gets a wide range of responses. I'm interested to see what the SMC literati opine).

EDIT: From playing with others' Japanese chisels and the one set I have, what you describe isn't uncommon. One thing you may notice is that the handle clears the workpiece when the chisel rests on that first ~1/2" of the back, i.e. it's set up as a slick. I have no idea if that's the intent, just what I've observed.

Jim Koepke
06-05-2016, 8:13 PM
I ordered an inexpensive set of Japanese chisels to give a try, just to see if I liked them. These, specifically: http://www.amazon.com/dp/B004GBKYN2/...apanese+chisel

Maybe I didn't look hard enough, but I couldn't find any sizes listed.

I like the philosophy of Warren Buffet in things like this, "I don't buy what I do not understand." I do not understand Japanese chisels. So it is unlikely any will be sought out by me. Maybe if they showed up at a yard sale or something at a low price I might become interested.

jtk

Derek Cohen
06-05-2016, 8:15 PM
Hi Luke

I suspect what you have found is that the socket section of the handle is difficult to keep off the stone as you lap the back of the blade. If this section, even the very start of it, touches the stone, then it lifts up the blade at the socket end and creates a back bevel on the blade. Yes, No?

If yes, then you must be careful to only lap the back of the blade so that this lies absolutely flat on the stone. Keep the socket off the stone. You will need to remove the back bevel. The worst of doing all this is that you are working with the hardened steel.

Regards from Perth

Derek

Warren Mickley
06-05-2016, 8:27 PM
I have never used a Japanese chisel. But I can tell you that making a convex bevel is a horrible practice. It is just a really sloppy method and it yields a sloppy edge. A consistent bevel allows one to get a precise and repeatable angle for the bevel.

Toshio Odate is adamant on this point; Shokunin (Japanese craftsmen) do not use convex bevels or secondary bevels.

Stanley Covington
06-05-2016, 8:53 PM
Luke:

Without pictures it is hard to properly evaluate the problem. Perhaps, as Derek suggests, you are allowing the kuchigane, or ferrule, to ride up on the stone. I think you would notice it, however.

What you have bought is the cheapest of the cheap, mass-produced, 4th rate chisels made (probably on the sly in China) for Kakuri, a company not known for quality, for sale in home centers to amateurs that will never ever even try to sharpen the chisels. They are throw-away tools.

The first clue is the price, which is less than a set of 3 professional-grade screwdrivers.

The second clue is the name Kakuri.

The third clue is the two reviews by people who obviously don't know anything about chisels. Just look at their comments: "very nice and sharp," and "Exelente?." Also, look at the other items they reviewed. These guys didn't have anything to do that day but write reviews.

Sorry to say, but you wasted your time and diamond stone trying to true them.

If you still want to try to make them flat, go ahead and put them on a grinder, and save your stones for removing the grinder marks. Or use them as they were intended to be used: Bang away until they are dull, then throw them away.

Stan

Luke Dupont
06-05-2016, 10:01 PM
Luke:

Without pictures it is hard to properly evaluate the problem. Perhaps, as Derek suggests, you are allowing the kuchigane, or ferrule, to ride up on the stone. I think you would notice it, however.

What you have bought is the cheapest of the cheap, mass-produced, 4th rate chisels made (probably on the sly in China) for Kakuri, a company not known for quality, for sale in home centers to amateurs that will never ever even try to sharpen the chisels. They are throw-away tools.

The first clue is the price, which is less than a set of 3 professional-grade screwdrivers.

The second clue is the name Kakuri.

The third clue is the two reviews by people who obviously don't know anything about chisels. Just look at their comments: "very nice and sharp," and "Exelente?." Also, look at the other items they reviewed. These guys didn't have anything to do that day but write reviews.

Sorry to say, but you wasted your time and diamond stone trying to true them.

If you still want to try to make them flat, go ahead and put them on a grinder, and save your stones for removing the grinder marks. Or use them as they were intended to be used: Bang away until they are dull, then throw them away.

Stan

Ah - I see. Well, I didn't pay full price for them; Amazon had them "used" -- someone just opened the package and sent them back, I guess. Perhaps that should have been a clue ;) I was, really, just interested in them to see if I liked the ergonomics of Japanese chisels, and firmer-style chisels as opposed to bevel edged chisels. I wasn't under the impression that I was getting quality chisels, but then, there are plenty of inexpensive but decent chisels in the western world in that price range. For future reference, what Japanese chisels would you recommend to novices?

I am very curious about one point, though; I have no idea what the previous recipient did with the chisels (though, there isn't evidence that they were sharpened), but the first half inch or so of all the chisels was very consistently ground at a slightly different angle to the rest of the back; such that I would assume it was done by design. They were like this when I got them, and no evidence that the socket had touched a stone. I did come up with this thread where someone was describing the same thing; his Japanese chisels, apparently a more expensive brand, also had this feature: http://www.sawmillcreek.org/showthread.php?162007-Japanese-chisel-out-of-flat

Is this something you're familiar with?

I guess, given the price range of the chisels, I should not be fussy about the backs. They're quite flat enough to work, and I can sharpen them even if it's a little tricky. Probably should take your advice and save my stone for better chisels.

Mike Holbrook
06-05-2016, 10:45 PM
The backs of Japanese chisels are typically hollowed out, concave, only the edges are flat. Such is the design of these chisels. They do something similar to plane bottoms. Less friction in use I believe...

If you are interested in Japanese tools I might suggest you pick up a copy of Toshio Odate's book "Japanese Woodworking Tools: Their Tradition, Spirit and Use". You may even find a used copy on Amazon.

Luke Dupont
06-05-2016, 10:51 PM
The backs of Japanese chisels are typically hollowed out, concave, only the edges are flat. Such is the design of these chisels. They do something similar to plane bottoms. Less friction in use I believe...

If you are interested in Japanese tools I might suggest you pick up a copy of Toshio Odate's book "Japanese Woodworking Tools: Their Tradition, Spirit and Use". You may even find a used copy on Amazon.

I'm not talking about the hollow; I mean the first half inch or so near the edge is ground on a slightly different plane from the rest of the back, ignoring the hollow. The user in the thread I linked to seemed to have had Japanese chisels with this same feature.

Thanks for the book recommendation, though! I would like to learn more about Japanese tools and woodworking practice, so I'll probably pick up a few books in both English and Japanese. Stanley was kind enough to make some recommendations that I still need to check out!

Brian Holcombe
06-05-2016, 11:06 PM
Luke, from the sound of it, they're just very quickly finished from the maker. It's probably easier to make it look pretty than to make it flat.

I've had a few chisels where the finisher cheated a bit like that, but only very slightly. Even a little bit makes the process much longer to flatten the back entirely.

What you're talking about, where you need to grind the back entirely flat to remove that bit would cause me concern.

Luke Dupont
06-05-2016, 11:12 PM
Maybe I didn't look hard enough, but I couldn't find any sizes listed.

I like the philosophy of Warren Buffet in things like this, "I don't buy what I do not understand." I do not understand Japanese chisels. So it is unlikely any will be sought out by me. Maybe if they showed up at a yard sale or something at a low price I might become interested.

jtk

They are, very roughly, 3/8", 5/8", and 1".

You see, Jim, usually I intentionally buy the very thing I don't know about! I employ this method often at authentic Chinese / Indian / Mexican restaurants. I figure, if I always stick to what I know, then I won't get the opportunity to learn and add to what is known :D

I can't say that I would recommend these chisels, as I knew they were cheapo chisels when I bought them, and Stanley's reasoning stands. Though, I will say, they *seem* to be decent steel, and they're chisel shaped, so they have that going for them! Just between you and me, I think I like them quite fine for what they are - minus, possibly, the problem I'm having with the backs, depending on whether or not that is intentional, and standard practice, or just a cheap cost cutting measure.

Maybe my opinions will change when I try some high end chisels at some point, though!

Mike Holbrook
06-05-2016, 11:15 PM
Right Luke, I just thought I would mention the hollow since no one else had. Stanley and Brian will steer you straight. Good luck with your foray into the world of Japanese woodworking tools.

Luke Dupont
06-05-2016, 11:21 PM
Luke, from the sound of it, they're just very quickly finished from the maker. It's probably easier to make it look pretty than to make it flat.

I've had a few chisels where the finisher cheated a bit like that, but only very slightly. Even a little bit makes the process much longer to flatten the back entirely.

What you're talking about, where you need to grind the back entirely flat to remove that bit would cause me concern.

Well, I'm not grinding anywhere near entirely flat, but the edges around the hollow are significantly wider than they should be at this point - I'd be a tad embarrassed for any Japanese craftsman to see the back of my chisel ;)

I'm also a bit concerned for my diamond stone's longevity. This steel is surprisingly hard, and I'm hardly making any progress on a 300 grit diamond plate. I haven't got anything else that might work, other than sandpaper, perhaps? Might be too hard for that, though.

Derek Cohen
06-05-2016, 11:40 PM
Stanley is right - for these chisels use a belt sander, and then finish on your stones. They are not worth a lot of effort. Still, they are probably worth a little effort, and may pleasantly surprise you. One of the reasons they are so cheap is that they lack the time put into finishing them that other chisels have had.

Regards from Perth

Derek

David Wong
06-06-2016, 12:13 AM
Luke,
Is it possible the previous owner applied some variation of the "ruler trick", to put a back bevel on your chisels? Seem odd that they have a consistent 1/2" length of back bevel. Perhaps it is a manufacturing defect.

I have had a few Japanese chisels from different makers that had slight to significant convexity on the backs. Initially, I wanted to preserve the aesthetics of the chisel back, so I choose to flatten just the portion of back in front of the cutting edge, leaving some belly on the chisel. After using the chisels, if the belly caused me problems, I would flatten the entire back. For flattening, I would use some combination of sandpaper on a surface plate, silicon carbide grit on a kanaban, and 220 water stones.

Flattening a chisel with a belly will reduce the hollow, but the hollow is serving one of its purpose reducing the effort to flatten the back. Nothing to be embarrassed about.

Gary Howorka
10-15-2016, 11:43 AM
Know this is an old thread but thought this might be of interest to you.

https://www.youtube.com/watch?v=yRLyLZHR7ME

apparently this is common with Japanese chisels. This guy shows how to light tap the front until your back is all in the same plane. There is a second video on sharpening the bevels.

Gary




I ordered an inexpensive set of Japanese chisels to give a try, just to see if I liked them. These, specifically: http://www.amazon.com/dp/B004GBKYN2/ref=sr_ph?ie=UTF8&qid=1465167459&sr=1&keywords=Japanese+chisel

I got them, and after setting the hoops, went to sharpening, and I noticed that it was extremely difficult to lap the back. I started with the 1" chisel, and I couldn't get the last half inch towards the cutting edge in line with the rest of the back. I think I got it down to about 3/16" from the edge, after more than an hour of work on my diamond stone.

Then I realized, looking at the other chisels, that they too have the first 1/2" or so on a different plane from the rest of the back. This makes me wonder; am I supposed to leave them this way, and not lap them dead flat as one would do with western chisels? What, then, is the purpose of the hollow found in Japanese chisels?

Also, what should I do with my chisel that I've half-lapped? It nolonger has a large enough reference surface to sharpen only the tip with, but it also is still quite out from dead flat, meaning I can't just place it flat on the stone to sharpen with -- so, I effectively have the worst of both worlds. I am starting to wear away the hollow in the middle, which I know is not ideal. Should I try to re-establish that secondary flat which was originally there, or just commit to a dead flat back and spend a few more hours grinding?

Also, uh, is it some terrible, taboo practice to sharpen Japanese chisels with a convex bevel? This is how I sharpen my western chisels and planes, and what I've done already on my 1" chisel; I tend to prefer this method, and the resulting geometry. However, I've noticed that most Japanese craftsmen seem to keep a flat bevel and use that as a guide when sharpening, which is why I ask.

This is why I didn't buy expensive Japanese chisels right off the bat :D

Stewie Simpson
10-15-2016, 7:47 PM
It was interesting listening to the advice given within the video, and comparing that to the advice posted by members of the forum.

Stewie;

Brian Holcombe
10-15-2016, 10:32 PM
Phil Fuentes is a very talented knife maker and Japanese tool user. I've never used that technique of burnishing on a flat plate, since I generally just use a fine stone when tapping out, but it is a really neat idea.

peter Joseph
10-15-2016, 11:35 PM
I'm surprised no one else suggested that you send them back. If you want to try japanese chisels on the cheap, look at Grizzly's offerings. I was given a gift card probably a decade ago and decided to order a set of 10. I still use them nowdays (albeit very infrequently) but they remain very sharp between sharpenings and came to me almost dead flat.

Bill White
10-16-2016, 2:55 PM
I still adhere to the principle of "how much is enough". Do the chisels cut wood?
Not being a nay-sayer at all, but how scientific do we REALLY need to be when using our tooling?
Luke, if the chisels work........put 'em to work.
There. I've opened a REAL can of worms, but then I have hold fasts made by blacksmiths, planes from Stanley, chisels from Butcher, and (GASP) a Grizzly table saw.
Press on regardless.
Bill

Brian Holcombe
10-16-2016, 3:18 PM
There is a reason why Japanese chisels should be setup correctly, and the reason is that it makes further maintenance very easy. Put the work in upfront or later on down the line, whichever you prefer.

Stanley Covington
10-16-2016, 7:48 PM
Know this is an old thread but thought this might be of interest to you.

https://www.youtube.com/watch?v=yRLyLZHR7ME

apparently this is common with Japanese chisels. This guy shows how to light tap the front until your back is all in the same plane. There is a second video on sharpening the bevels.

Gary

Tapping out the back of chisels is seldom necessary, but occasionally is useful the first time one sets up a new chisel or badly abused one. It won't work on narrow chisels, however, so don't expect it to fix all your problems.

The video was very abbreviated, and Mr. Fuentes was never given time to perform any of the steps to completion.

The steel plate or kanaban he used is the traditional tool. The video did not show him using the silica carbide powder normally applied for serious work. And of course, he did not talk about the pitfalls of the kanaban. I think a diamond plate is safer for most folks, if more expensive.

During the next video on sharpening the bevel, once again, he was never given time to complete any step but was rushed on to the next quickly. Too bad. Consequently, the bevel was hideous and nowhere near sharp.

I wasn't impressed with his technique on the stones, although it was typical for most guys with a moderate experience. Take shorter strokes, use the entire surface of the stone including the edges, use the mud more effectively, and not skew the blade so much.

2 cents

Stewie Simpson
10-16-2016, 8:55 PM
Mr Fuetes offered Luke a traditional Japanese method to resolve the issues with the backs of his Kakuri Chisels. Kudos to Gary Howorka for posting that video.

Stewie;

Stanley Covington
10-16-2016, 11:23 PM
My main point was that Mr Fuentes was unfortunately not provided enough time by the presenter to give a thorough demonstration.

Mr Fuentes's sharpening technique, at least what we saw in the video, was entirely adequate, but I pointed out some ways he could have used the stones more efficiently. Just my opinion, of course.

Prashun Patel
10-17-2016, 9:35 AM
Stan and Stewie: Tried to keep the essence of the debate but remove the more ripe top notes.

I have gotten a number of PM's advising that my editing is heavy handed. I apologize and really respect all of your contributions. I'm humble with respect to the content. So, please realize that I don't take editing lightly.

I am attempting, though to preserve an atmosphere where posters can challenge each other without getting personal. The personal attacks are regrettably often interwoven with relevant thoughts on the topic. I edit to avoid throwing babies out with the bathwater. When I feel my editing is controversial, I send the poster a PM. But sometimes, I just have to break up a fight. There isn't enough time to edit and also send PM's in this case.

I always remain open to restoring certain posts if you think you or someone in particular has been wronged. But I urge you to give me specific instances to correct.