Part Deux - The Gennou BTS

[Stanley Covington]

I am starting a new thread because I need to add a significant amount of new information to my older gennou thread, but if I just appended the old thread, most people would just blow it off as more chitchat. So here goes.

History
We all grew up using hammers with handles designed to fit a fictional person. These handles were designed to be easily mass-produced, and to look great hanging on the hardware store wall. Most importantly, the product development gurus and marketing departments of the tool conglomerates told us (and continue to tell us) that the tools they design to grace the Borg's shelves are perfect in every way.

Modern people have all but forgotten how to make a proper tool handle, but it wasn't always that way. If you want to check for yourself, look through the old tool catalogs and see how axe handles have become curvier and much thicker over the last 80 years. Notice how the grain of the wood is totally ignored. These changes have not resulted from efforts to make tools more functional or to achieve superior ergonomics, but once again, to make it easier to mass-produce handles from lower-quality materials, while apparently improving the outward appearance.

The handle described below is an interpretation of the gennou handle developed over several centuries by the Anaya carpenters of Japan. The gentleman that taught it to me 30 something years ago is now in his late 90's, and was around when the Anaya trade was still vibrant. The decision of whether it is more aesthetically attractive or not I will leave to you.

Ergonomic Factors
1. Handle Length: There is a handle length best suited to your body, the way you work, and the work you plan to do. Figure it out. It will take some trial and error. Some general guidelines follow, but are only a starting point.
2. Handle Grip Area Dimensions: Ditto No.1 above.
3. Head/hand orientation: The human body does its best work with a hammer or gennou when the plane of the flat striking face is the very close to the bottom edge of the wrist at impact.
4. Head Angle: The human body tends to rotate the gennou's head during the swing, but standard handle design blithely ignores this indisputable fact. We need to deal with this.

The Guidelines

"The Code is more what you'd call "guidelines" than actual rules." Captain Barbarossa

Overall Length
I could spend a lot of electrons describing why, but time does not permit, so take my word that the handles of all your gennou and hammers should have a similar grip configuration, and most especially, the same overall length measured from the end of the handle (butt) to the center of the striking face.

It is true that, assuming the same angular velocity, additional head speed can be obtained by using a longer handle. Golf clubs use this principle. If you are a golfer, you know how hard it is to get really good with those 14 clubs, all with different length handles. Perhaps, like me, you have experienced the occasional slice, or chili dip, or even the dreaded Adolf Hitler. Different length handles change everything.

Unlike the Game of Pings, when using a hammer to cut a mortise or chop dovetails, we do not have the luxury of modifying our stance, waggling the hammer, staring into the distance like Clint Eastwood to estimate how hard to swing, or talking with our Bag Rat about the best line or whether to use a 7 or 9 iron.

If you need more power when using a hammer or gennou, don't use a longer handle, use a heavier head. In this way, your precision, speed, rhythm, and efficiency will improve, and all your gennou's and/or hammers will become part of your hand working without conscious thought or even the need to see the gennou or hammer.

As seen in the photo below, with the head held in a flat palm (not a fist), and the fingers wrapped over the head, the butt just touches the bicep tendon. In my case, by total coincidence, this is 12". I am not a big man at 5'8", nor do I have big hands. This is another of those guidelines.

Grip Dimensions
The grip is important. Don't plan on choking up on the handle. The swing is the swing. The drawing below has the dimensions for my medium-sized gennou. For larger ones, I make the grip/butt bigger. For lighter heads I use a smaller grip/ butt. The size of your hands, and the number of your fingers, will dictate this shape, so I suggest you make your first gennou handle from an inexpensive wood like hickory or ash (can be bought cheaply as an axe handle from the Borg) instead of expensive ebony or bubbinga, and make the grip area oversized. Then use the handle for a few weeks or months, shaving it down little by little until you achieve the perfect fit.

I like my handles to flair towards the gennou's front edge, but some people like them straighter. Personal preference. Whatever you choose, the toe of the handle's front edge should not extend past the plane of the head's flat striking face.

Head Angle
Contrary to what the tool department at Monkey Wards taught us, it is the nature of the human body for the wrist to lead the hammer head during the swing, with the result that, if the handle is oriented perpendicular with the center of the head, the hammer's face will hit the nail or chisel handle at an angle. Test this for yourself. Color the face of your hammer or gennou with an inkpad, marking pen, or Dykem, then use it to cut a mortise, checking the striking face and chisel handle frequently. You will notice that the color is scrubbed off the bottom half of the hammer's or gennou's face first, and that the ink marks on the chisel are off-center. This means that impact forces are acting to kick the chisel out of alignment, decreasing accuracy, and beating up your hand. This wasted impact force also ruins your rhythm (pendulum theory) and slows your work down.

Clearly, to maximize transfer of energy to the cutting edge, and to minimize both wasted energy and the off-center forces that kick our chisel out of proper alignment, the centerline of the head needs to be oriented closely in-line with the centerline of the chisel or nail at the instant of impact.

When gripping the hammer (across the palm and not in a fist; See the pictures of my grip in my previous Gennou post), your pinkie should just fit between the front edge of the handle and the plane of the flat striking face. This means that if you place the gennou on a flat tabletop as shown in the drawing, and press straight down on the head so the face is flush with the tabletop, the toe of the handle will either be floating above the tabletop, or perhaps almost touching, while your pinkie will fit neatly between handle and table. Please refer to the drawing below.

After you have finished your handle, do the inkpad test. If the center of the striking face is scrubbed clean first, and center of the chisel handle becomes inked first, then you have the right angle. If not, some adjustment may be necessary.

Handle Curvature
This curvature is a matter of personal preference, but it also has a structural purpose as well. That said, some people prefer to make the handle straight, and to accommodate the change in angle at the point where the handle exits the head's eye. This is entirely acceptable, but realize that you will need really tough wood for a handle made this way to be durable. I prefer to deal with this change in angle in a smooth curvature. I think it looks better. I know it fits my hand better. And my engineering background tells me that I want to avoid sudden transitions that induce stress concentrations, especially when grain runout is possible. But this is not a rule, only a guideline, as Captain Barbarossa would say.

Tasting the Pudding
How do you know if your handle works?

First, of course, is the ink transfer test described above.

Next, you need to determine if your efficiency and accuracy have improved. This may take some time, but you will probably notice that your mortise work goes faster, and the holes are cleaner (assuming your chisels are worthy).

Here is an experiment you should try. It is called the blind swing test. It will require a lab assistant. A sexy outfit is preferred, maybe leather, maybe lace. After you have used the gennou with its new handle for a few weeks, set it on your bench within reach, and close your eyes. Have your assistant, perhaps a friend, or neighbor, or girlfriend, or wife, or even a bench kitty (but never your neighbor's girlfriend's wife's dog) change the gennou's orientation by turning it over, upside down, sideways, or whatever. Next, with your eyes still closed, grab the gennou with your hammer hand, and grip it properly.

If your grip is shaped as shown in the drawing with a flat at the back edge and a radiused front edge, you should be able to instantly orient the handle in your hand without any fumbling.

Then, with your eyes still closed, swing the gennou at the end of a stick of wood gripped in your off-hand fist, like it is a chisel. You should be able to strike the stick with the flat end of the gennou solidly and squarely on the first, or perhaps second try. Brian Holcombe did the first time. Perhaps it was some virtue exuded by his planing robe and embroidered planing slippers? Enquiring minds want to know.

If you miss the stick consistently, it may be you are not yet accustomed to the handle, or it may be that you need to make it shorter or longer. Perhaps the grip needs to be adjusted. It is absolutely worth figuring out.

Fitting Handle to Head
The handle's tenon is a friction fit in the eye. NO WEDGES.

If the eye is sloppy, true it with a file. If is curved a bit inwards (convex) at the center, no problemo, but if the walls are concave or twisted, some filework is called for. The better gennou blacksmiths, such as Kosaburo (Hasegawa san RIP) and Hiroki (Aida san), made/make their eyes very precisely centered, properly shaped, and very clean. This is a difficult thing to accomplish, and one detail mass-produced gennou consistently get wrong.

Sadly, there are a few famous Japanese blacksmiths that make gennou heads that are beautiful works of art on the outside, but sloppy on the inside. The most common defect is twist. Other medium-grade but well-know brand names have even worse QC problems such as centering problems or acute skiwampus. Such problems are difficult to deal with. Caveat emptor, Skippy. But so long as the eye is centered and square, judicious filework will alleviate most internal problems.

Shave the handle's tenon just a hair fat, and hammer it into the eye. It will take a lot of heavy blows, and there is risk of actually breaking the handle due to the stresses. The dome at the handle's butt is absolutely essential to this operation. You will regret it if you neglect to make it.

Do not be a country bumpkin and perform kigoroshi on the tenon. Kigoroshi works fine on softwoods, but simply damages and weakens hardwoods. There has been a lot of engineering research in Japan at the University level on the art of kigoroshi, and the facts are indisputable. I don't have time in this post to discuss the history and reasons behind this technique.

Don't use wedges. They will weaken and split the handle. Remember, you are making a high-quality tool, by hand, for a high-quality craftsman (thee). This is not piece-work in a Guangzhou factory.

I know that some of you have been taught, by people you respect, to let the tenon project from the eye. This is a matter of personal preference, but in my very well informed opinion, it makes as much sense as gluing AstroTurf onto the hood of a Porsche. I recommend you either cut the tenon flush, or leave it slightly recessed in the hole. The recessed tenon makes it easy to tap the handle a bit deeper and tighten it up when dry weather comes and shrinks the tenon.

If the tenon becomes loose, immediately fix it. Like right now. You can either tap the tenon further into the eye, or shim the tenon with quality paper. Cotton rag typing paper is best, and newspaper is worst. This will fix most problems.

Finishing the Handle
My sweat and/or skin oils reacts with some varieties of wood. Walnut turns my hands purple. My hands quickly turn oak black. So I apply a finish to my handles both to keep them looking nice, but more importantly, to slow changes in the handle's moisture. I have an involved finishing process I use which I do not have time to describe here. But I recommend you at least soak several coats of 100% thinned polyurethane into the wood over several days, sanding with wet/dry sandpaper while the wood is still wet, letting the slurry harden after each soaking coat. After wet sanding the last time down to bare wood, wipe off all the finish and slurry from the wood's surface. Be sure to seal the grain at the butt and eye tighter than a submarine's hatch. This is an understated but very durable and effective finish. Or you can leave the wood bare. Neither Captain Barbarossa nor I will say aught.

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[Derek Cohen]

Hi Stanley

Interesting about "kigoroshi on the tenon". When I handled the Tenryuu head I received from So several years ago, the method he advocated was to use kigoroshi. To make matters even "worse", the tenon projects past the head. In defense, the head has remained firm and the gennou has been a delight to use ...

http://www.inthewoodshop.com/ShopMadeTools/AHandleforaGennou_html_1e4a9f24.jpg

Regards from Perth

Derek

[Stanley Covington]

Hi Stanley

Interesting about "kigoroshi on the tenon". When I handled the Tenryuu head I received from So several years ago, the method he advocated was to use kigoroshi. To make matters even "worse", the tenon projects past the head. In defense, the head has remained firm and the gennou has been a delight to use ...

http://www.inthewoodshop.com/ShopMadeTools/AHandleforaGennou_html_1e4a9f24.jpg

Regards from Perth

Derek

Is the flat striking face oriented up or down in the photo you attached?

Stan

[Derek Cohen]

Stan, I strike with the flat side of the head. In the picture above, the flat side is facing down. This appears to be the opposite way you appear to use it, but the way So showed me. It feels comfortable.

I've dug up an older photo of the gennou being used dovetailing ...


http://www.inthewoodshop.com/ToolReviews/KoyamaichiChisels_html_m24c33744.jpg

Note that this is a higher bench than I use today.

Regards from Perth

Derek

[Brian Holcombe]

So's website shows them made much closer to Stan's description, with the curve heading toward the flat side of the gennou and the tenon not protruding from the head.

I made two handles with Stan's guidance and both my wrists and chisels vouch for his method. I have straight handles as well so I can tell first hand the advantage. I also had one going the opposite direction which I never used because it would kill my wrist, now I use it all the time because I turned the handle around on Stan's advice and it's become a wonderful tool to use.

The hit now being straight on causes all of the force to work downward, not toward the sides. The effect is much more accurate and effective chopping with less sharpening being required as the edge is not being levered in the cut.

http://i27.photobucket.com/albums/c181/SpeedyGoomba/1F74F832-49BE-49AF-92B1-9774200012FE_zpsipgot4pl.jpg

There is also a video on Youtube of Masayuki fitting a handle to one of his gennou, it's a funate style head and very clearly the handle is curving toward the flat.

https://www.youtube.com/watch?v=-s5kpZmU6_g

[Derek Cohen]

Brian, my contact with So was several years ago. We corresponded by email, and he provided instructions in that medium (not off his website). This continued after I had built the gennou, and I recall he was very enthusiastic about it at the time. Please note that none of this makes any difference. The gennou works well. Should I change it. Will it work better if I did?

Regards from Perth

Derek

[Reinis Kanders]

Love this info. I have some Warrington pattern hammers from LV with lose heads. Would this type handle benefit that type hammer? I will give it a try when I have some time.

[Ron Bontz]

Interesting. Thanks for posting.

[george wilson]

The grain direction on Western hammers is to have the growth rings vertical to the direction you swing the hammer. Now I don't feel so bad about making mine like those above. I wanted to see the quartered grain. Probably doesn't matter on small hammers anyway.

[Brian Holcombe]

George,

I like the quarter grain as well. All of my Japanese supplied handles are growth rings perpendicular to 45 degrees to the direction of the swing. I always assumed it was so that the handle would not let go of the head in the dry months.

Also, I took note of your preference for perfectly straight grain in hammer handles when I was hunting for wood in my workshop for use on these. I did my best to orient the grain to mimick the curve of the handle. The ash handle accomplished that a little better than the kingwood one.

[Pat Barry]

It looks cool for the growth rings to be circular in the end of the handle. I know George's point about the grain direction is important for high force hammering but otherwise, its a bit overkill. Its like everyone knows that you want the growth rings on a baseball bat to be parallel to the ground when you hit a ball (don't hit on the trademark) to reduce breakage, but hitting a ball on the trademark is actually going to impart more velocity on a baseball due to the recoil (Controversial I know, but there is no doubt it feels better to the hitter!).

[Stanley Covington]

The grain direction on Western hammers is to have the growth rings vertical to the direction you swing the hammer. Now I don't feel so bad about making mine like those above. I wanted to see the quartered grain. Probably doesn't matter on small hammers anyway.

George:

Ideally, the grain should be oriented in the direction of the swing as you correctly pointed out. This is the rule in Japan too. But the piece of split Osage Orange wood Matt gave me did not permit the normal orientation. Since the grain is so tough and stringy, and as you observed, the head is lightweight, I went with the quartered orientation seen in the photo. I would not do so with a heavier head.

Stan

[Stanley Covington]

Love this info. I have some Warrington pattern hammers from LV with lose heads. Would this type handle benefit that type hammer? I will give it a try when I have some time.

I think it would be of benefit. Length and grip considerations aside, The only situations I can imagine where an angled head would not help is where you need the hammer's face to reach into a tight place and the handle might get in the way, such as when toenailing down between rafters or installing blocking. Also, blacksmiths do not like this handle because it places their hand closer to the hot metal.

Stan

[Mike Holbrook]

More info. on making handles for gennou is great, because I want to customize handles for quite a few tools. I think I will practice with my original gennou which came with a handle, before putting handles on the gennou I bought from So. I made some ash splits and may make a few more with other woods. I have been collecting interesting wood for handles. I have two Adzes and a few axes I may customize handles for too. I have a nice piece of Gumi I got from So that I will wait on until I have a clue.

Here is the Gumi and a few green wood tools I would like to make custom handles for:

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Judging by the curves I see in Stan's handles I think I may have chosen a piece with just about the right amount of bend at one end.

[Derek Cohen]

Stan, a question for you that I do not recall being asked (or answered) ..

Why is the handle bent? How does this differ from a straight handle? (OK, two questions :) ).

Regards from Perth

Derek

[Kees Heiden]

Interesting stuff. All the Japanes tools are pretty remote for me, but it is fun to read about.

One think I don't understand is the aversion against wedges. Billions of hammers, axes and whatnot have a wedge to hold the handle to the head. They don't seem to cause a lot of problems overall. Why making a problem of it?

[Stanley Covington]

Interesting stuff. All the Japanes tools are pretty remote for me, but it is fun to read about.

One think I don't understand is the aversion against wedges. Billions of hammers, axes and whatnot have a wedge to hold the handle to the head. They don't seem to cause a lot of problems overall. Why making a problem of it?

Kees,

Notice how small the eye is. A wedge through that will weaken it unless the handle is really fat below the tenon. All a wedge does is either splay the tenon in a tapered eye, or compensate for poor tolerances in either the eye or the tenon.

This is a Formula 1 race car type handle, so it does not handle a trailer hitch well.

Stan

[Stanley Covington]

Stan, a question for you that I do not recall being asked (or answered) ..

Why is the handle bent? How does this differ from a straight handle? (OK, two questions :) ).

Regards from Perth

Derek

Derek,

I thought both points were covered in my original post, but I will try to clarify. Sorry for the confusion.

The handle is bent, and differs from a straight handle, for two reasons.

First, the wrist tends to naturally lead the head when swinging a hammer, causing the axis of the head to be rotated out of alignment with the axis of nail or chisel being struck. This is not efficient. Angling the head away from perpendicular to the handle helps bring the head back into proper alignment at Impact improving energy efficiency, increasing cutting or nailing precision, and with straighter rebound, rhythm and speed as well. Please try the inkpad test in my first post.

Second, and intimately related to the first reason, this handle locates the wrist and hand where they are most efficient in relation to the point of impact.

Give it a try.

Stan

[Kees Heiden]

Kees,

Notice how small the eye is. A wedge through that will weaken it unless the handle is really fat below the tenon. All a wedge does is either splay the tenon in a tapered eye, or compensate for poor tolerances in either the eye or the tenon.

This is a Formula 1 race car type handle, so it does not handle a trailer hitch well.

Stan

Well, make the hole larger, problem solved!

Probably some eastern-western philosophy thing, which might be one of the reasons that it all remains fairly remote to me.

[Stanley Covington]

Well, make the hole larger, problem solved!

Probably some eastern-western philosophy thing, which might be one of the reasons that it all remains fairly remote to me.

Make your handle like a guy that knows how to work wood....Problem solved!

[Kees Heiden]

And take a blacksmith that makes the hole exactly right.

[Derek Cohen]

Derek,

I thought both points were covered in my original post, but I will try to clarify. Sorry for the confusion.

The handle is bent, and differs from a straight handle, for two reasons.

First, the wrist tends to naturally lead the head when swinging a hammer, causing the axis of the head to be rotated out of alignment with the axis of nail or chisel being struck. This is not efficient. Angling the head away from perpendicular to the handle helps bring the head back into proper alignment at Impact improving energy efficiency, increasing cutting or nailing precision, and with straighter rebound, rhythm and speed as well. Please try the inkpad test in my first post.

Second, and intimately related to the first reason, this handle locates the wrist and hand where they are most efficient in relation to the point of impact.

Give it a try.

Stan

Easy enough Stan - I'll simply turn the gennou around and use the other side :)

Regards from Perth

Derek

[Stanley Covington]

Easy enough Stan - I'll simply turn the gennou around and use the other side :)

Regards from Perth

Derek

Derek:

Sounds like an excellent idea. Its a beautiful handle.

Please let us know if it makes a difference. In the case of your squat daruma, it may not be obvious.

Stan

[Christopher Charles]

Stan (and others), many thanks for taking the time to document your thoughts and experience. However, you're killing me. I've been smitten with the Tenryu tsuchime gennou since Derek posted photos of his. I may have to pull the trigger even though it would be the cart before the horse as I've also been resisting buying a set of japanese chisels...

I've gathered that a ~225 g head is favored by most for general light bench work and heavier (e.g. 375 g+) are best for mortising and chopping? It is tempting to order a 225 g shikaku and a 375 g daruma and try both, but that's not a luxury I can afford right now.. FWIW, I currently use a 18 oz Wood is Good mallet for most everything. Any suggestions?

Thanks!
C

[Stanley Covington]

I've gathered that a ~225 g head is favored by most for general light bench work and heavier (e.g. 375 g+) are best for mortising and chopping? It is tempting to order a 225 g shikaku and a 375 g daruma and try both, but that's not a luxury I can afford right now.. FWIW, I currently use a 18 oz Wood is Good mallet for most everything. Any suggestions?

Thanks!
C

Christopher:

Not sure what the question is, but I will throw some suggestions out.

As you mentioned, the style and weight of hammer you order should depend on what kind of work you are going to do.

Non-Japanese seem to like the daruma style, and although I own and use them myself, they are a specialist style not intended for general use. In fact, they are thought by many here in Japan to be ugly little fellas used by guys who can't find the end of their chisel or the head of the nail. I have seen carpenters ridicule other carpenters who bring a daruma to the jobsite. They are used a lot by carvers and tategushi (joiners) but for different reasons.

For most applications, a standard ryoguchi head, which is longer and thinner than the daruma, is preferred because it is stabler (larger moment of intertia) and therefore resists twisting out of alignment during the swing better. This makes it easier to use from different heights and different angles. It also has less air resistance. But, if like a joiner, you need to sit down to cut 300 identical small joints from a fixed position and height and angle in a couple of hours, then the daruma is the way to go

Of course, I am just talking about physics. One can do very good work with a daruma in all situations. The prejudice against the ungraceful appearance of the daruma is a matter of fashion I suppose.

If you are a carpenter, then the 375 (100匁) gennou is the standard general purpose weight gennou head. When using tataki nomi for cutting deep and wide mortises in timbers, or 16d or large nails, heavier gennou are necessary.

For most of the small joints guys make for furniture or cabinetwork as a hobby, the 60匁 (224gram) is very good, especially for very precise work. 80匁 (300gm) is a good choice too with more chopping power. Really, you need a several. 375 would not be my first choice for furniture or cabinet work.

I hope this rambling answered your questions.

Stan

[Christopher Charles]

Thanks Stan.

You are correct--I did not ask a clear question. I do indeed do primarily small scale work/furniture rather than larger scale work such as carpentry or cut large mortises.

I'll likely end up with several in the end, but the question I was trying to ask was, if just one for now, which weight? And which style? My thanks for your providing some good info on both questions and based on my reading, you'd suggest a ~225 g daruma as a good staring spot.

I'll be interested to hear what other say about which weights and styles they use most often.

Best,
C

[Matt Lau]

Chris,

I had the same questions as you, and got them very well answered by Stan via email/chat etc.


What's your price range?

You could always start with a simple "user grade" dogyu hammer from Stu (tools from Japan) http://www.toolsfromjapan.com/store/index.php?main_page=index&cPath=344_369_470_471 or Hida Tool http://www.hidatool.com/woodworking/hammers and move to the "connoisseur grade" stuff after you've used your hammer for a few months/years. It'll be under $40 a hammer. Get both a 225 and 300 g hammer from Stu for under $40!
Personally, I'd avoid fancy finishes, gold plating, etc.
I'd avoid a daruma for your first one (it's actually sorta cumbersome in the hand--much less precise feeling, especially for small joints like in chairs, small furniture).
If you don't hit the thing dead center, it sort of twists a little (although people like Derek Cohen seem to make a great job with it).

Definitely go and make your own handle--it just costs a trip to the firewood pit (unless you're a nut like me, where I got hand split billets of osage orange billets off ebay).
A bent handle feels much more natural in swing...and it's much more satisfying.

After using both for a few months, splurge.


I'd recommend a Hiroki or Kosaburo (major brag, thanks Stan!) if you can afford it, as they are both incredibly well made.
I have a Hiroki 180 g from Deiter Schmidt (used mainly for chopping very precise notches in spruce guitar bracing) and a 375 Kosaburo from Stan.
If Stan didn't tell me it's from Kosaburo, I would not know the difference as fit, finish, balance, workmanship are both at a sublime level.

Before getting the Hiroki, I never understood the fascination/obsession with gennou that the Japanese have.
After ( with the right handle (self-made of course)), I can COMPLETELY understand what it's about--the feeling of the head sucking down on a well honed chisel is a feeling that is so "right" that I feel like crying manly tears of gratitude.

-Matt

ps. You may want to PM/email Stan regarding chisels/gennou. I was really impressed with his "user grade chisels" that cut at least as nice as my Masashige.
I think that he's also got some new guy making inexpensive, high quality HSS chisels (not bad if you're abusive on your tools, and don't want to baby them.
He is a wealth of knowledge and loves Japanese tools.

[Brian Holcombe]

Stan's 'user grade' chisels are superb. They outperform the Yamahiro mortise chisels that I have, holding an edge at a shallower angle.

The Tenryuu is nice, but there is something just incredible about Kosaburo and Hiroki gennou.

[Derek Cohen]

Derek:

Sounds like an excellent idea. Its a beautiful handle.

Please let us know if it makes a difference. In the case of your squat daruma, it may not be obvious.

Stan

Well Stan, I had a chance to install butt hinges today and used the gennou.

I do agree with you - I now much prefer the curve away from me. The gennou felt more controlled.

Regards from Perth

Derek

[Stanley Covington]

Well Stan, I had a chance to install butt hinges today and used the gennou.

I do agree with you - I now much prefer the curve away from me. The gennou felt more controlled.

Regards from Perth

Derek

Derek:

Thanks for the update.

You make beautiful things from beautiful wood, Derek, that gennou included. May it serve you well and long.

Stan

[Derek Cohen]

Thanks Stan. I ordered a 225gm Tenryu Tsuchime Shikaku gennou head from So today. It will be interesting to experience the difference to the 375gm, which I have got so used to. It seemed the right thing to do when I realised that the brass chisel hammer (with nylon on the faces) I use for unhooped Western chisels is 8 oz (225gm).

I'll curve the handle the other way this time!

Regards from Perth

Derek

[Mike Holbrook]

Thought I would revive this thread since I am interested in parts of the same topic.

I am interested in types of wood for handles and where to take the wood from. I pruned trees this spring and saved likely looking wood. The wood is largely limbs or the trunks of small trees. I believe I read somewhere that limbs do not make great handles? I suspect that with lighter gennou it may not matter. I also bought handle raw material from So when I ordered a gennou head. The wood looks like a limb to me.

I have trimmed limbs from apple, oak (white & red), maple, bald cypress, hickory, dogwood, ash logs.... I know that many old tool handles were apple. I have been cutting likely looking limbs from those I pruned this year. I also prune out small trees which leaves me with entire small trunks. Now that I have better splitting tools and skills, I can split straight grained billets from logs. I am trying to decide how much of what to save.

[David Wong]

A couple of years ago, I made a 375g genno handle out of a small limb from a western live oak. The limb was drying outdoors for probably a couple of years. Just some branch trimmings I had saved and leaned against a wall to dry. Live oak is very tough, but can be brittle. So far it has held up well. Sorry, but I am traveling now, so I can't post a picture. I also recently purchased a Japanese wild cherry branch as a handle for a 250g genno. I have collected other random small limbs from tree trimmings, with the intention of making more handles. If they break, they are relatively easy to replace. As you said, lighter weight genno's will probably be ok.

[Mike Holbrook]

Thanks for your thoughts and corroboration of some of my thoughts David.

I have plans to move and I am attempting to harvest wood, particularly fruit tree wood from 10-15 year old plants/trees. I say plants because I harvested a dead trunk from a blueberry "shrub" yesterday that seemed quite hard so I saved it too. Rabbit Eye blueberries can get very large. I planted a Bald Cypress many years ago that is now quite large. I think the bald cypress may also be called white cypress...I'm not sure why this tree has lived as it is on the side of a hill that is not always wet, but it has. Lots of knees and everything. Next up will probably be pear trees, maybe more dogwood or Black Locust if I can find any down in the valley.

I plan to take down a few trees to make usable splits from too. I plan to collect "billets" from splits to have pieces to make chairs from. Smaller pieces may make good tool handles. Split pieces dry faster than I think many people realize, especially if some sort of homemade kiln is used. There is a limit to how much I want to move though. I should add that fruit wood is great for smoking/grilling too.

[Stanley Covington]

Thought I would revive this thread since I am interested in parts of the same topic.

I am interested in types of wood for handles and where to take the wood from. I pruned trees this spring and saved likely looking wood. The wood is largely limbs or the trunks of small trees. I believe I read somewhere that limbs do not make great handles? I suspect that with lighter gennou it may not matter. I also bought handle raw material from So when I ordered a gennou head. The wood looks like a limb to me.

I have trimmed limbs from apple, oak (white & red), maple, bald cypress, hickory, dogwood, ash logs.... I know that many old tool handles were apple. I have been cutting likely looking limbs from those I pruned this year. I also prune out small trees which leaves me with entire small trunks. Now that I have better splitting tools and skills, I can split straight grained billets from logs. I am trying to decide how much of what to save.

Mike:

I can share some guidelines again, and my experience.

You need a wood that is hard enough to stand the shear forces, but not brittle. Softwoods are typically not good because the fibers compress and the head loosens up over time. Plenty of hardwoods are too brittle. Others have oils that let the head slip off. Some expand and contract too much with humidity changes.

White oak, either American, European, or Japanese are good, as are hickory and ash and maple, assuming the grain has very little runout. Through-grain is very important.

Bocote is not good. Teak is not good. Ebony and rosewood are not good. I made a handle from Japanese mountain cherry, but found it to be too soft.

I have made several handles from Japanese black persimmon, and have been very pleased with their performance. I recently made a handle from Osage Orange. I have not used it much, but I think it will be excellent, especially after the color mellows out. i now understand why they make bows from it.

I suspect most fruitwoods would perform very well. If the blank has a center, I would be careful to confirm it has reached equilibrium moisture content and is done splitting and cracking.

I have been told by the old boys here in Japan that the two best woods for tool handles are a popular flowering shrub called Utsugi (Deutzia crenata https://en.wikipedia.org/wiki/Deutzia), and another wood called Ushikoroshi (Rhamnus davurica var.nipponica (http://www.weblio.jp/content/Rhamnus+davurica+var.nipponica)), which translates to "Cow Killer." After much searching, I recently acquired samples of each wood, but have not done anything with them yet.

Interestingly, I bought the ushikoroshi from a steel retailer here in Tokyo that also sells mining tools (picks and rock hammers etc.). The owner of the store confirmed that this wood makes the best handles. A old carpenter friend showed me his gennou handle made from utsugi, and said it is superior to ushikoroshi, but more difficult to find in larger diameters. I am not aware of commercial sources, but hope to develop some in the future.

You should have no difficulty finding a satisfactory wood wherever you live.

Regards,

Stan

[Mike Holbrook]

Stanley,

Thanks once more for sharing your experience.

Mostly I have been trying to decide which fruit wood to use in the smoker/grill and which to save. I am also aware of the opportunities for fruit wood north of where I currently live, in the north Georgia mountains. Lots of apple orchards in the area. I find experimenting with different woods and finding where they may best be used very interesting. I would love to experiment with those woods you mention when you find a way to offer them.

Maybe when you visit your sister in Cedar Town we can share a bottle of wine or port in the North Ga. mountains.

[Derek Cohen]

OK Stanley, I orientated the gennou head the correct way this time! :rolleyes:

A new Tenryu Tsuchime Shikaku head from So, weighing 225gm, which is the weight I have come to prefer for bench chisels. The 375gm Tenryuu Daruma was a little too much for lighter work.

I made the handle an 1" shorter than the 375gm as it does not require as much downforce.

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou1_zps7cp5gx6s.jpg

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou2_zpsdo5z5bi9.jpg

Comparison of the two handles ..

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou4_zpsk6e4mhdy.jpg

And the 275gm on its own. The handle is Fiddleback Jarrah ..

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou5_zpsdfubb8np.jpg

Regards from Perth

Derek

[Stanley Covington]

OK Stanley, I orientated the gennou head the correct way this time! :rolleyes:

A new Tenryu Tsuchime Shikaku head from So, weighing 225gm, which is the weight I have come to prefer for bench chisels. The 375gm Tenryuu Daruma was a little too much for lighter work.

I made the handle an 1" shorter than the 375gm as it does not require as much downforce.

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou1_zps7cp5gx6s.jpg

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou2_zpsdo5z5bi9.jpg

Comparison of the two handles ..

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou4_zpsk6e4mhdy.jpg

And the 275gm on its own. The handle is Fiddleback Jarrah ..

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou5_zpsdfubb8np.jpg

Regards from Perth

Derek


Beautiful work and beautiful wood! I love the fiddleback Jarrah's appearance. Please educate us about this wood. Hardness, oilyness, friction, vibration transmission, brittleness, etc..

How did you determine the handle lengths?

Very attractive heads too. Are the eyes straight and un-twisted?

Thanks,

Stan

[Derek Cohen]

Thanks Stan.

All is nice and straight, and the balance is good.

By "eyes" do you mean the sides/tenon into the head? Here is the other side - a little of the tenon showing. I know you like them flush with the head. I still prefer a little peeking out (but made this much shorter this time around) ..

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou6_zpsf3loy3vb.jpg

This Jarrah is not dry and brittle, as much of the stuff I use for furniture. It has been air dried, is close grained, and I sensed more elasticity when shaving it to shape. The grain is interlocked, but overall, the figure had a natural curve that I could follow.

Length? The 375 gm handle is a good one. I just got lucky there (guided by instinct and not a formula). I decided to make this one a little shorter as that would promote a little more control. I will know more when I have used it enough.

Regards from Perth

Derek

[Stanley Covington]

Thanks Stan.

All is nice and straight, and the balance is good.

By "eyes" do you mean the sides/tenon into the head? Here is the other side - a little of the tenon showing. I know you like them flush with the head. I still prefer a little peeking out (but made this much shorter this time around) ..

http://i13.photobucket.com/albums/a262/Derek50/Mallets%20and%20hammers/Tenryu%20Tsuchime%20Shikaku%20225g/Gennou6_zpsf3loy3vb.jpg

This Jarrah is not dry and brittle, as much of the stuff I use for furniture. It has been air dried, is close grained, and I sensed more elasticity when shaving it to shape. The grain is interlocked, but overall, the figure had a natural curve that I could follow.

Length? The 375 gm handle is a good one. I just got lucky there (guided by instinct and not a formula). I decided to make this one a little shorter as that would promote a little more control. I will know more when I have used it enough.

Regards from Perth

Derek

Thanks. Yes, "eye" is the term used i the US for the tenon hole for axes and hammers, etc.

Stan

[Phil Mueller]

Don't know how I missed this from May, but thanks Stan. I enjoyed your first post and this adds some great information. I was interested in the discussion on wood types for handles. Thinking about what might be easily available to me, I spied a crabapple in dire need of prunning. Do you think a branch from this might be worth a go?
Really appreciate the insight and time it takes for you to share it.

[Stanley Covington]

Don't know how I missed this from May, but thanks Stan. I enjoyed your first post and this adds some great information. I was interested in the discussion on wood types for handles. Thinking about what might be easily available to me, I spied a crabapple in dire need of prunning. Do you think a branch from this might be worth a go?
Really appreciate the insight and time it takes for you to share it.

I have never used crabapple, but so long as the piece you use has little grain runout and is at or below equilibrium moisture content, it should work just fine.

Stan

[Mike Holbrook]

341162 341163 click to enlarge

Trying out a few different handle shapes, with more or less curve in the handle, various ways to finish the ends, various grip shapes.....The 300g Hiroki handle has a coat of WATCO. The 450g Tenryu is a piece of what I think is white oak that has been stable for a year or so. The 225g Tenryu head is on a lighter piece of apple.

I finally decided the apple wood I harvested for my gennou handles is dry enough to use. I have been impressed with how well the heads seem to grip the wood. It does take a fair amount of coaxing to get one of those heads off while working the handle down to a tight fit.

I am wondering how close, to the top of the head, the handle needs to go? I believe Stanley has mentioned leaving the handle material a little shy of the top of the opening. Not being sure how much the wood may move I have been trying to leave the heads a little shy of the top, at least until I am confident the wood is very stable. I'm just not sure how far from the top to leave them? I am guessing the 225g needs to be closer than the 450g. The heads seem to be relatively solidly seated after they get past the mid point, slightly convex area, in the middle of the handle recess. I am wondering if say 1/4 to 3/8" from the top is reasonable early on or whether I need to get them within 1/16 or so right away?

The Hiroki head was easier to seat the handle in. I imagine this relates to Stanley's comments about the better heads having the most precisely made handle recesses. I am having a little more difficulty with the Tenryu heads. The Tenryus are more difficult to get past the convex area in the middle. I suspect that the convex area is a little larger or cruder.

[Stanley Covington]

341162 341163 click to enlarge

I finally decided the apple wood I harvested for my gennou handles is dry enough to use. I have been impressed with how well the heads seem to grip the wood. It does take a fair amount of coaxing to get one of those heads off while working the handle down to a tight fit.

I am wondering how close, to the top of the head, the handle needs to go? I believe Stanley has mentioned leaving the handle material a little shy of the top of the opening. Not being sure how much the wood may move I have been trying to leave the heads a little shy of the top, at least until I am confident the wood is very stable. I'm just not sure how far from the top to leave them? I am guessing the 225g needs to be closer than the 450g. The heads seem to be relatively solidly seated after they get past the mid point, slightly convex area, in the middle of the handle recess. I am wondering if say 1/4 to 3/8" from the top is reasonable early on or whether I need to get them within 1/16 or so right away?

Mike:

Very nice work!

Glad the apple wood is gripping the head tightly.

Monitor the butt closely over the next few weeks. Not sure how long it has been since you cut the wood, but if the moisture content causes problems, heaven forfend, the handles will start to crack at the butt. If this occurs, it is common for the corresponding shrinkage in the tenon to cause the head to loosen up.

I like to leave my handles approximately one half the thickness of the tenon recessed in the eye when the gennou is new. But it doesn't always turn out that way. There are no rules, only what works for you. It sounds like you grasp the logic behind this detail as it was first taught to me. Nothing at all wrong with the handle being flush with the eye. The sight of a handle sticking out past the eye always bothered me like a baseball cap worn sideways, but that is just my opinion.

Stan

[Mike Holbrook]

I have been working the handles and then bagging them with shavings. They have not shown any cracking for a month or more so I think they will be good. These are more of an experiment anyway, so if they crack I want be too disappointed. I still have the piece of gumi (sp?) I got from So. I just roughed it out, saving it for when I know what I like.

A little further along now..
341191

[Christopher Charles]

Hello Mike,

Great looking work! I'm curious about your thoughts on how the Hiroki and Tenryu compare. I'm considering dipping my toes and springing for a quality gennou (which really means jumping into the deep end...). But the budget is limited right now...

Also, I was reading through old threads the other day and I believe you'd been shopping for paring chisels--did you decide on something?

Stan, interesting that you find a bit of handle sticking up less appealing than a recessed handle--my intuition says the opposite, probably because a recessed handle produces the illusion that the head might come flying off :)

Best,
Chris

[Mike Holbrook]

Chris,

Not to put words in Stanley's mouth but I think once you fit a handle to either type of head you will see that the design of the head keeps the heads in place vs a wedge or extending the end of the handle out the far end. The inside of the heads have a convex area, about half way between the two sides of the head. Once you get the handle up past that area it is wedged in without needing a "wedge".

I decided to harvest and form my own gennou handles from wood on my property. Drying the wood, even relatively thin branches takes a while. I just got my heads on handles today so I have not had much time to use them yet. I did find the Hiroki head easier to fit a handle to. I believe the reason is the care the maker takes in making the hole for the handle. If you look into the opening in a Hiroki you will see that great care was taken in shafting the head. The Tenryu heads are well made too but it is easy to see the difference. I understand that it is a little odd to be talking about how well the shaft in these heads are made, right up until you fit a handle to one.

My handles felt like they were fairly solid once they got past the convex area in the middle of the heads I was mounting them to. Leaving the handle slightly recessed allows room to drive the head on further if the wood shrinks, still keeping the handle even with the top of the gennou head.

[Brian Holcombe]

Done properly the heads lock on very tightly. If ever concerned just try to take one back off, lol.

[Derek Cohen]

Done properly the heads lock on very tightly. If ever concerned just try to take one back off, lol.

Yes :( I attempted to remove the 375gm head so that it might be reversed - I am resigned to using the domed side. Damn the person who built the handle! :D

Regards from Perth

Derek

[Stanley Covington]

I have been working the handles and then bagging them with shavings. They have not shown any cracking for a month or more so I think they will be good. These are more of an experiment anyway, so if they crack I want be too disappointed. I still have the piece of gumi (sp?) I got from So. I just roughed it out, saving it for when I know what I like.

A little further along now..
341191

Mike:

If you want to use limbs and trimmings, there is an interesting rabbit hole you may want to fall into. In Japan, for some years it has been a fad to use Yamazakura (mountain cherry) limbs and trimmings for gennou handles, and to leave the bark on. Cherry bark, at least this variety, is a pretty dark burgundy in color, and relatively smooth. In fact, cherry tree bark is a traditional finish for boxes, and containers. I don't know if you have any wood with a similarly attractive bark, but it does look cool. I actually made a handle for one of my gennou from this wood, but found the wood to be too soft to deal with the pounding.

Some pics I found on the web follow.

Stan

[Stanley Covington]

Stan, interesting that you find a bit of handle sticking up less appealing than a recessed handle--my intuition says the opposite, probably because a recessed handle produces the illusion that the head might come flying off :)

Best,
Chris

Chris:

Actually, I think a handle trimmed flush with the head looks best, but the fact is that a recessed head is more practical for a brand new handle. The handle sticking out of the eye looks untidy to me. But that is just the way I was trained.

Stan

[Stanley Covington]

Yes :( I attempted to remove the 375gm head so that it might be reversed - I am resigned to using the domed side. Damn the person who built the handle! :D

Regards from Perth

Derek

When it comes time to remove a handle, the recessed eye is very handy!

If you haven't tried it yet, I have found the best way to remove a head from a handle i intend to reuse to be to cut a tenon just a little smaller then the eye on the end of short, hard stick. Then drill a hole in a board big enough for the handle's butt to drop through, and use the stick to drive the handle out.

Stan

[Stanley Covington]

Some more pics of a pretty handle and head (not mine).

Stan

[Christopher Charles]

Thanks all for the clarifications--definitely makes sense.

Stan, that is some serious bling. At least for those looking here...

[Stanley Covington]

Thanks all for the clarifications--definitely makes sense.

Stan, that is some serious bling. At least for those looking here...

Chris:

It does not belong to me.

It's a little too gaudy for my taste, and will not age gracefully. In fact, I would be embarrassed to be seen with it in my hand in public. They have one like it at Suiheiya for a couple of grand, but it is not as well made as a Kosaburo or Hiroki head IMO.

Stan

[Mike Holbrook]

Great info. again Stanley. I just spent an hour or two this AM studying how to make furniture out of twigs and sticks with the bark still on. The wife is very interested in many of the design styles that have come out of Adirondack architecture in the Adirondack Mountains here in the US. Much of the work I have seen does not seem substantial enough for my tastes but I plan to incorporate limbs with bark into some of our furniture. About to order a tapered tenon cutter from LV which is how the more substantial work is joined. Starting around the Cedar Town area north this style is popular. I have seen homes with entire sets of kitchen cabinets and bathrooms made from sticks with the bark still on. There are trees/shrubs in the neighboring mountain areas that are often used for this kind of work.

I love the appearance of the gennou with the bark handle. I'm not sure how practical a handle with the bark on it is long term. I still have a apple wood handle curing with just the very top of the bark scraped off, as an experiment.

I hear you Brian/Derek. I tried to get my handles relatively precisely fit which entailed testing then removing the heads quite a few times. I have the same Thor hammer Derek does and mine is panting in my shop, still recovering.

Great idea for removing the handles Stanley. I will find time to make the pieces of the jig you mention. I just happen to have dowel/tenons made from long grain white oak that I can trim to fit.

[Stanley Covington]

Great idea for removing the handles Stanley. I will find time to make the pieces of the jig you mention. I just happen to have dowel/tenons made from long grain white oak that I can trim to fit.

I would encourage you to not repeatedly install and remove the head when making a handle. You should work so as to install the handle only once. Repeatedly removing it cause the head to loosen more easily.

You need to work the tenon area very carefully to accomplish this to avoid removing too much material..

Stan

[Mike Holbrook]

I feel you Stanley. It occurred to me that I might not want to remove the head too many times, still it was a learning process in terms of what size to make those first tenons. Hopefully, next time I will be closer the first time. Not sure if I will make it in one attempt but I will work towards that goal.

[Patrick Chase]

Chris:

It does not belong to me.

It's a little too gaudy for my taste, and will not age gracefully. In fact, I would be embarrassed to be seen with it in my hand in public. They have one like it at Suiheiya for a couple of grand, but it is not as well made as a Kosaburo or Hiroki head IMO.

Stan

It's the Japanese equivalent of a Bridge City plane - Pretty, but not intended for hard use [ducks for cover].

[Christopher Charles]

I agree, not to my taste either. But then I've never been one to go for bling :)

https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=bling+definition

[Dan Kirkland]

Stanley, all this information has got me really wanting to try my hand at this. I have piece of zebrawood that could easily be made into a handle. How do you feel it would hold up? I have a 245g and 125g funate genno head that I could use it for.

[Stanley Covington]

Stanley, all this information has got me really wanting to try my hand at this. I have piece of zebrawood that could easily be made into a handle. How do you feel it would hold up? I have a 245g and 125g funate genno head that I could use it for.

Dan,

I have zero experience with zebra wood. I suggest you examine the pieces you are considering using and determine a few characteristics:

1. Can the handle be cut to provide a high percentage of continuous grain through the tenon and at least 3/4 the length of the handle?

2. Is this piece likely to shiver ( crack) under the vibration of tens of thousands of impacts?

3. Is this wood likely to shrink and swell with seasonal atmospheric humidity changes enough to cause the head to loosen?

4. Is this wood oily? Does it have a high enough coefficient of friction to hold the head in place, or will it encourage slipping?

5. Is this wood strong enough to resist impact loading on the tenon without yielding?

6. Will this wood transmit vibration to my hand like a tuning fork?

Stan

[Stanley Covington]

Here are some pics of a small wooden box finished in cherry bark in the traditional Japanese fashion. This is a toothpick box at the restaurant where I took the little lady for dinner last night.

Notice that the bark is not perfect. The variety of bark used for this craft is this color without any staining or applied finish. It is fairly durable in that it does not dry out and crumble. But since, at least in the case of furniture and boxes, it is essentially an applied veneer, it is not especially tough. However, it would probably be OK for a tool handle attached to the tree limb where it grew.

Stan341653341654

[Mike Holbrook]

Nice Stanley!

I believe hickory "twigs" are often used in the N. Georgia mountains. I think the bark on young hickory is relatively stable compared to many other barks. I tried to find pictures but what I found is for sale, in houses for sale... so I don't think I should post links. A search for Twig Furniture should provide plenty of examples. Some of the furniture made from twigs is several thousand US dollars and more. Young green wood can also be bent without steaming.

[Dan Kirkland]

Stanley, thank you for the info. I have a new/old head coming from Japan that I'll make a zebrawood handle for. We'll see how it turns out.

[Stanley Covington]

I translated a statement written on Mr. Hiroki Aida's homepage (http://aitoyo.net/aida.html) you might find interesting. It reflects precisely the way I feel about the best tools.

"Handtools are an extension of the hands, and must function as part of the body in order to do good work. I want craftsmen to be able to work comfortably and enjoyably."

The more a tool can be adapted to fit the user's hands and function as a part of his body rather than something he is manipulating, the more efficient and pleasureable will be the process of working with that tool. After all, more than half the fun of working with tools is the experience of the tool doing exactly what we want it to do without conscious thought or struggle.

There are limits to how much you can adapt a tool to your hand and body. Wooden bodied planes: Somewhat. Chisels: Not much, but perhaps a little. Squares: Nada. Marking gages: Yes. Saws: Yes, quite a bit. Gennou and hammers: A lot. Gennou and hammers are the only high-velocity tools in the Neanderthal workshop.

Mr. Aida uses the name "Hiroki" on his products. He does excellent work, all freehand forging. So good in fact that he has orders backed up for three years.

[Patrick Chase]

There are limits to how much you can adapt a tool to your hand and body.... Chisels: Not much, but perhaps a little.

IMO you can adapt Western chisels (esp socket chisels) to your body quite a lot. You don't hear so much about people re-handling Japanese chisels though.

[Brian Holcombe]

People re-handle them.

[Dan Kirkland]

So here's my attempt, I haven't ever made a tool handle before so this was a new experience for me. Zebrawood handle and tung oil finish. 126g head. Any thoughts? What could I do better?

The curve of the handle isn't as steep as some of the ones that are shown previously in this thread, not sure if that's a bad thing? and the handle wasn't as flush in the eye as I'd like, but it stays on and you'd have to really hammer it off to remove it. I did use kigoroshi to fit the head.

https://c1.staticflickr.com/9/8716/28685445072_74987116dc_z.jpg

https://c6.staticflickr.com/9/8067/28791115725_32702e64cc_z.jpg

[Stanley Covington]

So here's my attempt, I haven't ever made a tool handle before so this was a new experience for me. Zebrawood handle and tung oil finish. 126g head. Any thoughts? What could I do better?

The curve of the handle isn't as steep as some of the ones that are shown previously in this thread, not sure if that's a bad thing? and the handle wasn't as flush in the eye as I'd like, but it stays on and you'd have to really hammer it off to remove it. I did use kigoroshi to fit the head.

https://c1.staticflickr.com/9/8716/28685445072_74987116dc_z.jpg

https://c6.staticflickr.com/9/8067/28791115725_32702e64cc_z.jpg

Dan:

Looks very nice!

Its different than what I would make for myself, but what fits me may not fit you. I suggest you use it and see how it performs.

Don't forget to try the ink test and the blind swing test after you get used to it. These will help you determine if adjustments are necessary.

Stan

[Pat Barry]

Dan:

Looks very nice!

Its different than what I would make for myself, but what fits me may not fit you. I suggest you use it and see how it performs.

Don't forget to try the ink test and the blind swing test after you get used to it. These will help you determine if adjustments are necessary.

Stan
The head / handle angle on this hammer looks very odd. It's like the intended purpose of this one is for use as a tack hammer since that is the side which is perpendicular to the he handle shafts at the head. This also places the grip in a seemingly poor position for use on either face of this hammer. I wonder if this is the handle form that is typically used with this hammer head.

[Mike Holbrook]

Nice! Thanks for the quote from Hiroki Stanley, well said.

I may be about to start on phase two of my handle making experiments. Now that I have all this additional information from Stanley. After fitting a few heads I think I can estimate the required size better now, not needing to do as much test fitting to get the size correct.

I have been saving a piece of Gumi wood I got from So and I have been drying more apple wood limbs as well. I like the apple wood handles in terms of the texture, appearance and strength of the wood. My Hiroki head will eventually get the Gumi handle but it may get another "test" handle first.

[Dan Kirkland]

The head / handle angle on this hammer looks very odd. It's like the intended purpose of this one is for use as a tack hammer since that is the side which is perpendicular to the he handle shafts at the head. This also places the grip in a seemingly poor position for use on either face of this hammer. I wonder if this is the handle form that is typically used with this hammer head.

It may very well not be the typical one. But I did hammer about 25 short brad heads with it and it went fine. If I'm not mistaken the Funate style of genno (which this type is I think) has one face intended for driving nails and the other elongated section is for use as a nail set. I'm sure Stanly or Brian can correct me on that.

[Stanley Covington]

It may very well not be the typical one. But I did hammer about 25 short brad heads with it and it went fine. If I'm not mistaken the Funate style of genno (which this type is I think) has one face intended for driving nails and the other elongated section is for use as a nail set. I'm sure Stanly or Brian can correct me on that.

The funate style often comes with an eye oriented to rotate the face of the hammer, and so may not benefit from a curved handle. It typically has a slightly domed striking face. Therefore, the geometric guidelines I wrote for the ryoguchi (two-faced) gennou may or may not be entirely applicable.

The funate is a handy tool, originally preferred by ship carpenters. Great for nails and trim work. The nailset end is also very handy for tapping out the hollows of plane blades. While it works for striking chisels, and can do kigoroshi, it is a compromise tool for these operations, intended to do a great job with nails.

More popular in the Kansai area than the Western Kanto area.

I think Dan will need to decide what works for him and what doesn't. The key is to be prepared to make a new handle when you decide the current one can be improved on, and you realize how to improve it. This is also why I do not encourage using expensive exotic woods for your first gennou handle.

Stan

[Dan Kirkland]

Stanley, I would've preferred to use cheaper wood as well, but the Mrs was getting at me for keeping all those "extra bits" and I had to use it for something ;)

I have another larger funate head that I'll experiment a bit more with

[Stanley Covington]

Ah, yes. I understand the predicament!

[Pat Barry]

Nailset? I pictured the smaller end being used as a tack hammer, not a nailset. I think it would be difficult to use as a nailset. That is, unless they were very large nails, in which case that little hammer is not enough for the job anyway. What size is the small end? I'd guess maybe 1/4 inch square. That's a strange size for a nail set.

[Stanley Covington]

Nailset? I pictured the smaller end being used as a tack hammer, not a nailset. I think it would be difficult to use as a nailset. That is, unless they were very large nails, in which case that little hammer is not enough for the job anyway. What size is the small end? I'd guess maybe 1/4 inch square. That's a strange size for a nail set.

My funate has a very small pointy end. 2mm square? An accomplished carpenter can pound in a nail, then flip the hammer around and set it below the surface without skipping more than a beat. You really need to develop a strong instinct for where the pointy end is at to do this consistently. Ship carpenters did this all day long.

There is a style called Yamakichi ("mountain luck") similar to the funate (meaning "ship hand"), but squatter and with a less pointy end. I prefer it to the funate style because it is less pointy. Different strokes for different folks.

[Pat Barry]

My funate has a very small pointy end. 2mm square? An accomplished carpenter can pound in a nail, then flip the hammer around and set it below the surface without skipping more than a beat. You really need to develop a strong instinct for where the pointy end is at to do this consistently. Ship carpenters did this all day long.

There is a style called Yamakichi ("mountain luck") similar to the funate (meaning "ship hand"), but squatter and with a less pointy end. I prefer it to the funate style because it is less pointy. Different strokes for different folks.
They must be very accomplished to do that IMO. I have enough trouble managing to set finish nails one at a time using my regular nail set and hammer. LOL

[Dan Kirkland]

So I've been a bit obsessive about this as of late. I had one more cutoff piece of zebrawood that I wanted to use, but before I cut into it I got ahold of some nice pieces of ash to experiment with the shape/length etc... according to Stanley's guidelines.

About 6 handle shapes later I found a shape, length, thickness and curve that really works well for me. And thus we have this.

The head weight on this one is about 245g
https://c6.staticflickr.com/9/8429/28477795653_be354c1581_z.jpg

Compared to my smaller hammer it's a little different. The small one is the 126g one I posted before. I have used it alot in my luthiery work and found it satisfactory, but I might experiment more with it in the future as well. But for now it's nice to have the pair and with these two I can handle most jobs.

https://c3.staticflickr.com/9/8199/28850421930_20d291e910_z.jpg

[Brian Holcombe]

My white ash handle, was a tad short so it has now become a template. The new handle is in white oak.

http://i27.photobucket.com/albums/c181/SpeedyGoomba/9F6A9340-6CF1-4F24-A99A-FBAA008D660A_zpssj0ezese.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/A277B7ED-C8E5-4917-A55B-89B03A1AEB99_zpstqyvkxwr.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/407E8D77-E0D5-4F9D-BB65-3CCCC0194B84_zpsbsmfj1dt.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/01E784B3-81B8-44C5-BEEA-D73207460A3E_zpspbkwsbyz.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/5EE5B37D-E221-40F8-B3D8-98BF78909BF7_zpsdesgbmsj.jpg

[Stanley Covington]

My white ash handle, was a tad short so it has now become a template. The new handle is in white oak.

http://i27.photobucket.com/albums/c181/SpeedyGoomba/9F6A9340-6CF1-4F24-A99A-FBAA008D660A_zpssj0ezese.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/A277B7ED-C8E5-4917-A55B-89B03A1AEB99_zpstqyvkxwr.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/407E8D77-E0D5-4F9D-BB65-3CCCC0194B84_zpsbsmfj1dt.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/01E784B3-81B8-44C5-BEEA-D73207460A3E_zpspbkwsbyz.jpg

http://i27.photobucket.com/albums/c181/SpeedyGoomba/5EE5B37D-E221-40F8-B3D8-98BF78909BF7_zpsdesgbmsj.jpg

Damn that's a nice head! A nice handle too!

As always, you do beautiful work, Brian.

I applaud your persistence in remaking the handle to fit you better. Please tell us why you concluded the first one was too short.

Stan

[Brian Holcombe]

Thanks Stan! Love that gennou, one of my favorite tools in the shop! I also polished the faces, I was in a hurry to put it to use initially but took my time this round and worked the faces to remove any lingering rust.

I had the length right on initially but had to tighten the handle and so rather than add paper as you recommended (and what I should have done!) I knocked it further down on the handle. I used it for a bit but swung and glanced off my thumb a few times and decided a new handle was the way to go.

So far I think the oak handle might be better than the ash for holding the head on tightly, but time will tell.

[Stanley Covington]

Remember to size the tenon carefully so it is a struggle to get it into the eye. 15 or 20 wacks. In fact, the eye should shave the tenon a bit when you are driving it in.

I also recommend heating the tenon for a few hours before final sizing during humid months, like it is here now (what a killer!) to shrink the tenon so it won't tend to loosen during dry winter months.

And finally, remember to seal at least the end of the tenon and butt of the handle with a good soaking of thinned varnish or PU to slow down moisture transfer and swelling/shrinkage.

The polished faces look beautiful! You have a tool that reflects your classic good taste, will serve you well, and will never wear out.

Stan

[Brian Holcombe]

Thank you! As always your guidance is invaluable!

I think this one was a success in that regard, it shaved some of the tenon and it took many whacks to install it, more so than the white ash handle. To allow it to be tighter still I chamfered the tenon so that it would compress. I don't recall if I did that the first time around but this time I made certain to.

I've shellacked the handle, but I'll go over the tenon again to make certain it is sealed. I think my error last time may have also been leaving the tenon unfinished.

It's hasn't been humid here at all (oddly enough) but I left it about 1/2" long so that I can tighten it down in the winter months, which I will likely need to do. Hopefully in the interim I'm not over-swinging.

[Christopher Charles]

Hello Brian,

That is a beauty. Would you mind sharing the rough dimensions you used for the handle stock? Especially the thickness. I'll soon be doing the same thanks to Stan (Thabks Stan!) and need to track down a proper piece of stock. Guessing from the photo, 4/4 won't quite do?

Best
C

[Brian Holcombe]

Thank you! 4/4 is a hair too thin, I believe I started with 6/4 stock. The handle butt would up slightly thinner than 6/4, but starting with heavier stock allowed me to correct for grain direction.

I am also under the impression that flat sawn is the best format for this, but I can't resist using rift.

Good to hear! Post up what you make!

[Mike Holbrook]

Nice one Brian!

Nice piece of white oak. I suspect that was a nice piece of wood to work with. The grain is ideal. You must have a nice supply of very good wood.

[Stanley Covington]

Hello Brian,

That is a beauty. Would you mind sharing the rough dimensions you used for the handle stock? Especially the thickness. I'll soon be doing the same thanks to Stan (Thabks Stan!) and need to track down a proper piece of stock. Guessing from the photo, 4/4 won't quite do?

Best
C

Its in the mail, Chris. Please post some pictures of how it turned out.

Stan

[Brian Holcombe]

Nice one Brian!

Nice piece of white oak. I suspect that was a nice piece of wood to work with. The grain is ideal. You must have a nice supply of very good wood.

Thanks Mike! I've been more and more particular about the grain in wood that I chose lately.

[Christopher Charles]

Thanks Brian, that helps (sort of--have lots of 4/4, not so much 6/4...). I doubt that your use of rift sawn will ever be an issue given the forces involved, even when mortising...

Stan-will let you know when it arrives and will indeed post pics.

[Christopher Charles]

Hello all,

With many thanks to the guidance and enthusiasm of Stan, Brian, Ken and others here, I've slipped down the Japanese tool slope.

Today a package arrived from Stan:
344100

Naturally, I reread Stan's guidance at the beginning of this thread and grabbed some red elm for a prototype handle. I cut it a bit long, sketched out a shape that was straight for the first 2/3rds of the length before curving. I left the tail long and perpendicular to the head to facilitate pounding the handle on. I roughed out the shape on the bandsaw and then used a block plane and spokeshave to fit to the head. I left it a bit fat, but it went on relatively easily (the elm is medium hard, but has the advantage of interlocking grain). Right now is the driest time of the year here, so I do hope it does not slip. Then again, this was intended as a pilot.

344102

344103

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[Christopher Charles]

344107344108

Initial test drive was very favorable and led to some tweaking. Need to sand and seal the handle, but will say that it is all very straightforward--total time start to (not quite) finished was less than 1.5 hours, including rereading Stan's guidance (though I did use a bandsaw...). Definitely recommend giving it a go, and again thanks to Stan and company. Now, off to make some stuff!

Best,
Chris

[Brian Holcombe]

Very nice work! And the genno is beautiful as well!

[Christopher Charles]

Thanks! I'm pleased with it for a prototype. The head probably deserves a finer piece of wood, but the elm does match the base of my workbench, so that's nice.

[Zuye Zheng]

Getting in on the action. Found a Hiroki funate gennou on the action site around the time of this thread so decided to to try a lighter, more traditional chisel hammer and fitting a custom handle.

The funate came with a black locust handle already fitted (a little loose so glued a shim and reattached), so based the 225g Hiroki daruma handle on it. It was from a catalina ironwood branch from the backyard that had been drying for a couple of months. The curve was a little too much (I think) since it was based off of the longer head of the funate, but will see how it feels.

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[Brian Holcombe]

Nice work Zuye, but you may want to simply continue the original curve without the return. I think you may find that bothers your wrist in use, but time will tell.

[Stanley Covington]

Getting in on the action. Found a Hiroki funate gennou on the action site around the time of this thread so decided to to try a lighter, more traditional chisel hammer and fitting a custom handle.

The funate came with a black locust handle already fitted (a little loose so glued a shim and reattached), so based the 225g Hiroki daruma handle on it. It was from a catalina ironwood branch from the backyard that had been drying for a couple of months. The curve was a little too much (I think) since it was based off of the longer head of the funate, but will see how it feels.

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Very nice results! Please let us know how the daruma works for you after you have driven it around the block a few times. As Brian pointed out, you may find the reversed curve at the butt a bit counterproductive since it may tend to rotate your hand, but that of course depends on how and where you hold it.

Stan

[Brian Holcombe]

Continuing this experiment (all of life is an experiment, right?) I had made the original handle for this genno from kingwood, well....the kingwood handle was a bit to thin and causing me to overlook this genno too often. I had to put an end to that, such a wonderful genno should be in regular use, just like its big brother with the white oak handle. The kingwood was safely removed and set aside for future repurposing and more appropriate white ash was chosen. I have spent a portion of the previous day cutting white ash into rift sections and so what remained was perfect for a genno handle, flat sawn material with the spine perfectly straight grained and quarter sawn.

Considering a few people commented on the grain direction of the handles I've been making, I decided to orient the flat sawn sides as recommended. The ash in question is quite strange looking and so it made for a great looking result (IMO).

https://brianholcombewoodworkerblog.files.wordpress.com/2017/01/img_5757.jpg

https://brianholcombewoodworkerblog.files.wordpress.com/2017/01/img_5753.jpg

[Stanley Covington]

Continuing this experiment (all of life is an experiment, right?) I had made the original handle for this genno from kingwood, well....the kingwood handle was a bit to thin and causing me to overlook this genno too often. I had to put an end to that, such a wonderful genno should be in regular use, just like its big brother with the white oak handle. The kingwood was safely removed and set aside for future repurposing and more appropriate white ash was chosen. I have spent a portion of the previous day cutting white ash into rift sections and so what remained was perfect for a genno handle, flat sawn material with the spine perfectly straight grained and quarter sawn.

Considering a few people commented on the grain direction of the handles I've been making, I decided to orient the flat sawn sides as recommended. The ash in question is quite strange looking and so it made for a great looking result (IMO).

https://brianholcombewoodworkerblog.files.wordpress.com/2017/01/img_5757.jpg

https://brianholcombewoodworkerblog.files.wordpress.com/2017/01/img_5753.jpg

Turned out beautiful, Brian!

As you wrote, the wood is a bit strange looking. It almost looks as if it is laminated.

What did you finish it with?

Do you find that your index finger gets a blister when using it?

Stan

[Brian Holcombe]

Thanks Stan! I had a couple boards of ash that are just so cool and bizarre looking, I'm glad to cut this out if and feature the grain.

I haven't used it enough to say, but so far this and the white oak have felt like an extension of my own arm. This one I carved a little heavier on the left side to see how it would affect the grip.

[george wilson]

I'm having a hard time getting much ash around here for some reason. But for hammer handles,I manage to get some pretty nice cut offs from the museum's millwork shop when they replace or repair parts of the under carriage on coaches.

I have a young lady silversmith friend who has some trouble with her wrist(I have warned her that she is not built for heavy duty hammering). She wants her hammers to have the "pistol grip" type shape. I find them a lot of trouble to make with my aches,and wonder if the Japanese style downward curved handles would be a decent substitute for the downward drooping bulbous type handles that are more traditional for smaller silversmithing hammers.

Re kingwood: I made a copy of an 18th. C. embroidery frame from kingwood on order. I'd think it too hard and brittle for slender handles.

[Brian Holcombe]

Certainly could work out nicely, these are very comfortable for a lot of hammering.

Stan attempted to talk me out of using kingwood, but I was sort of bent on it. In hindsight it was a goofy decision, but gave me the opportunity to do it right the second time. :)

[Stanley Covington]

That old-style Kosaburo head with the ashwood handle is so elegant... It belongs in a museum of art!

What did/will you finish it with? Or will you leave it nekid?

[Brian Holcombe]

Thanks Stan! Much appreciated! I finished it in shellac, just a pretty light buffing to keep it from getting dirty.

[Paul Saffold]

Thanks Stanley for your very detailed descriptions and advice. This is my first attempt. The next will have a bit more swell to the butt end. The wood, American sycamore, may be too soft in the long run. Time will tell if the head loosens. Haven’t used it much yet. Having put off doing this too long and I used what wood I had. Now knowing how simple it is to do I won’t hesitate to make others. No wedges :). Tried your diluted varnish method and like it so far. I usually use diluted boiled linseed oil on handles. Don't know why the photo is rotated.Paul354862

[Stanley Covington]

Thanks Stanley for your very detailed descriptions and advice. This is my first attempt. The next will have a bit more swell to the butt end. The wood, American sycamore, may be too soft in the long run. Time will tell if the head loosens. Haven’t used it much yet. Having put off doing this too long and I used what wood I had. Now knowing how simple it is to do I won’t hesitate to make others. No wedges :). Tried your diluted varnish method and like it so far. I usually use diluted boiled linseed oil on handles. Don't know why the photo is rotated.Paul354862

It looks really good,Paul. Great job!

How heavy is the head?

Some people like more flair at the butt, and others like them more slender. The old boy that first taught me liked them skinny as a tomboy. There is no right or wrong, only what works for you. It will likely take several tries to find the best shape and angle for you, so don't get too fond of a particular handle. Use each handle hard and be critical of the results, improving with each reiteration.

Good luck.

Stan

[Christopher Charles]

Hello all,

After chopping a bunch of mortises with my small gennou (240 g), I decided it needed a companion (350 g). Stan, as much as I would have liked a twin for my Hiroki, it was not in the monetary cards this time...at least the handles are both local elm :)

Now that summer travel is winding down, looking forward to getting back in the shop!

Best,
Chris
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[Stanley Covington]

Hello all,

After chopping a bunch of mortises with my small gennou (240 g), I decided it needed a companion (350 g). Stan, as much as I would have liked a twin for my Hiroki, it was not in the monetary cards this time...at least the handles are both local elm :)

Now that summer travel is winding down, looking forward to getting back in the shop!

Best,
Chris
366689
366690

Chris:

Sweet!

[Brian Holcombe]

Very nice!!

[Christopher Charles]

Thanks to you both, as the handles are much more elegant and ergonomic than I would have achieved on my own!