Sharpening Japanese Chisels; did I screw up?

[Luke Dupont]

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

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

[Reinis Kanders]

Sounds like a mess Upload some pictures, otherwise it is hard to judge.

[Patrick Chase]

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]

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]

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]

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]

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]

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/showthre...el-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]

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]

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]

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]

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

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]

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]

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]

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