Setting the Hoop - Japanese Chisels

[Brian Holcombe]

I didn't plan to do this, but I had a chance to reset one of my most used handles to show one of the guys on WC how I go about doing this. I owe Stanley Covington a great deal of credit, as it was not only a FaceTime conversation, but years prior to that a thread right here on SMC which set me on the right track. It's contributions like Stanley's that have me loving this board, and so I thought I'd share some photos.


First; a professionally setup chisel from Japan, notice there are no water stains and the wood isn't protruding out along the sides heavily.






Please ​Notice I have taken the handle off of the chisel before starting. I have little interest in injuring myself during this process, so I put the sharp part aside.

I cut the handle back to untouched wood. These are gumi handles, so they are incredibly hard wearing and have a certain springiness that makes them nice to use. My handle does not have any sharp ledges....because the hoop was radiused on the inside when I put it together a good while back.





To completely remove any lingering burr; I work the top of the hoop with a file, work the inside of the edge to a radius with a file, then finish up that edge with a carbide burnisher.





Same on the bottom





I install the hoop using a hoop setting tool and a mallet. I do not need to trim the wood or do kigoroshi The hoop is nicely radiused, so as it is knocked down onto the handle it is compressing the wood, that compression is what retains the hoop.





I didn't measure, but I wold guess that is about 1.5mm.





Finally, lightly peened. Note the radius on the top of the hoop will allow the wood to expand and not to shear off due to a sharp edge. If the wood shears off the wear process will accelerate.





Then, reinstall on the chisel.





Stanley trims the inside of the hoop with a cutting tool, since I do not own that cutting tool I use this method. Slight difference, his approach is quicker but same result.

[Frederick Skelly]

Thanks for posting this Brian. For me, the setup and maintenance techniques used for Japanese chisels seem a bit daunting, and have kept me from trying them. Setting the hoops was one of those tasks, and this post helped me learn.

(Though I'm still intimidated about having to eventually "pound out" part of the hollow back. - Sorry for the ignorant description. I don't know the correct one.- That task looks like a golden opportunity for me screw up a very finely made Japanese tool. )

Fred

[Sam Murdoch]

Thanks for posting this Brian. For me, the setup and maintenance techniques used for Japanese chisels seem a bit daunting, and have kept me from trying them. Setting the hoops was one of those tasks, and this post helped me learn.

(Though I'm still intimidated about having to eventually "pound out" part of the hollow back. - Sorry for the ignorant description. I don't know the correct one.- That task looks like a golden opportunity for me screw up a very finely made Japanese tool. )

Fred

There is always that . I'm like you on this one Fred. Thanks Brian for some guidance!

[Charles Bjorgen]

Duly noted, Brian. I'm over here too. I'm the guy who asked about this on WC.

[david charlesworth]

Fred,

It is not necessary to hammer the bevel of a chisel, except possibly very big ones.

Metal is removed from the back with a coarse stone, to preserve the hollow.

Even this is probably only necessary every few years, if you are careful with your sharpening.

I believe hammering is generally reserved for large plane blades.

David.

[Mike Holbrook]

Thanks Brian,

I picked up a few extra things to do before simply hammering the hoops into place. I was fortunate enough to have a hoop setter similar to Brian's. I checked the insides of the hoops for rough spots and then used the hoop tool to drive the hoops into place. Once the whoops were driven down relatively tightly, I used a gennou to expand the wood around the edges.

I was afraid of screwing something up too. It turned out that the job was fairly straight forward and not something I needed to fear. So far none of the hoops I have set has come off and none of the handles has chipped or cracked.

[Brian Holcombe]

Thanks gents.

Fred, uradashi or 'tapping out' sounds more overwhelming than it is, but in either case it is largely unnecessary for most chisels. I have used it on paring chisels where I want a to keep an even ura. Those same paring chisels do not have the steel coming up the sides (mimi) and so they are able to be worked much like a plane iron.

The exception to this being a situation in which the front edge has been ground into the ura, but that is mostly avoidable.

[Brian Holcombe]

In addition to setting the hoops Stanley guided me through a process of tuning the chisel tang, tuning the kuchigane (ferrule) and fitting the handle to the kuchigane. When the handles are created they are turned on a lathe to fit the ferrule, in doing so they typically leave an abrupt landing. In a heavy use chisel that abrupt stop can be driven to the point where the ferrule is no longer doing its intended job putting all of the driving forces on that landing rather then evenly throughout the ferrule. To prevent this that landing is removed.

First, the chisel tang. The shoulders are squared, sides are trued and any burrs are removed. The ferrule is then filed flat on the bottom and any internal burrs are removed.



Next, a wrap of tape is placed at about 6mm above the ferrule's landing on the handle. This is used as a gauge for the work that will follow. Lines are drawn from the corners of the mortise on the handle on down to the ferrule's landing, then those are divided. The material is then removed in facets at those lines, then the dividing lines, finally the area between those facets to create a nice even pattern while removing the landing. What is left is a nice conical shape that will allow the handle's ferrule to function properly.



Here is the assembled result.



And a slightly more dainty version for my lighter use chisels;

[Derek Cohen]

....
(Though I'm still intimidated about having to eventually "pound out" part of the hollow back. - Sorry for the ignorant description. I don't know the correct one.- That task looks like a golden opportunity for me screw up a very finely made Japanese tool. )

Fred

Fred

I posted the following on WC, where the thread began. The title was "Peening".

The end of the handle needs to cover the (edit: inside section of the) hoop. The edges of the hoop are sharp, and the wood is to cushion the end of the handle when pushed with the palm. (edit: I taper the outside of the hoop a smidgeon to remove the hard edge).

Look at the chisel on the right ...





There are two components to setting a Japanese bench chisel. The first is driving the hoop (about 2mm) below the the end of the handle. (edit: like Stanley and Brian, I do not recommend water. Instead, if needed, I use a file or chisel to remove a little of the handle surface to allow the hoop to move). The second is to peen the edges of the end of the handle. You want to move the wood and make it flow over the inside edge of the hoop.

Peening is the process of working the surface. To do this we need a hammer with a domed head - the traditional Japanese gennou is perfect (these have a domed end on one side and a flat end on the other side). A Warrington hammer is another.

To peen one does not hammer downwards. Instead you need to hammer at an oblique angle and simultaneously drag the hammer head across the surface, as if you were pulling the wood over the hoop. Several controlled gentle taps are better a single heavy-handed slam.


Give it a try.


Regards from Perth


Derek

[Frederick Skelly]

Fred,

It is not necessary to hammer the bevel of a chisel, except possibly very big ones.

Metal is removed from the back with a coarse stone, to preserve the hollow.

Even this is probably only necessary every few years, if you are careful with your sharpening.

I believe hammering is generally reserved for large plane blades.

David.

Thank you David!

[Frederick Skelly]

Thanks gents.

Fred, uradashi or 'tapping out' sounds more overwhelming than it is, but in either case it is largely unnecessary for most chisels. I have used it on paring chisels where I want a to keep an even ura. Those same paring chisels do not have the steel coming up the sides (mimi) and so they are able to be worked much like a plane iron.

The exception to this being a situation in which the front edge has been ground into the ura, but that is mostly avoidable.

Thanks Brian!

[Frederick Skelly]

Fred

I posted the following on WC, where the thread began. The title was "Peening".

The end of the handle needs to cover the (edit: inside section of the) hoop. The edges of the hoop are sharp, and the wood is to cushion the end of the handle when pushed with the palm. (edit: I taper the outside of the hoop a smidgeon to remove the hard edge).

Look at the chisel on the right ...

There are two components to setting a Japanese bench chisel. The first is driving the hoop (about 2mm) below the the end of the handle. (edit: like Stanley and Brian, I do not recommend water. Instead, if needed, I use a file or chisel to remove a little of the handle surface to allow the hoop to move). The second is to peen the edges of the end of the handle. You want to move the wood and make it flow over the inside edge of the hoop.

Peening is the process of working the surface. To do this we need a hammer with a domed head - the traditional Japanese gennou is perfect (these have a domed end on one side and a flat end on the other side). A Warrington hammer is another.

To peen one does not hammer downwards. Instead you need to hammer at an oblique angle and simultaneously drag the hammer head across the surface, as if you were pulling the wood over the hoop. Several controlled gentle taps are better a single heavy-handed slam.


Give it a try.


Regards from Perth


Derek

Thank you Derek!
Fred