Hammers to Use With Chisels Part 4 – The Chisel Cha-Cha

Stan Laurel

You can lead a horse to water, but a pencil must be led.

Stan Laurel

In previous articles in this series about hammers to use with our chisels, we discussed the varieties of suitable hammers, the appropriate faces on those hammers, and recommended some weight ranges. In this article we will examine some important hammer and chisel techniques you should consider that will make your chisel work more efficient and help your chisels last longer.

Your Most Humble and Obedient Servant hard at work. A dab of skin lotion might be nice.

The Chisel Wiggle

Something to keep in mind about our chisels when beating on them is that their cutting edges are intentionally and carefully hand-forged and heat treated by experienced blacksmiths (none with less than 40 years independent experience) to be especially hard to meet the demands of professional craftsmen who demand the extra sharpness and cutting longevity hard, fine-grained steel makes possible. They are not the sharpened Chinese screwdrivers sold by the big corporations that amateurs are accustomed to using nowadays.

To maximize the advantage such excellent steel affords, our Beloved Customers must avoid driving the chisel so deeply into the wood when cutting mortises, for example, that the extreme cutting edge binds in the wood forcing the user to wiggle the chisel forward and backward to loosen and extract it from the cut. I call this movement the “chisel wiggle.” I know this is contrary to what many woodworking gurus teach, but it is careless in the case of our professional-grade tools because binding the blade in the wood this way creates what we call a “high pressure cut” placing a tremendous amount of clamping force on the thin, extreme cutting edge. Doing the “chisel wiggle” in this high-pressure situation will damage the cutting edge dulling it quickly. If you doubt this, please dig out your hand-dandy loupe and do a before-after comparison.

In addition, the time lost extracting the chisel and the resulting interruption in the workflow caused by repositioning one’s hands, and perhaps even setting aside the hammer (egads!) while doing the chisel wiggle, makes it impossible to maintain an efficient cutting rhythm. If you doubt this, we double-dog dare you to do timed comparative tests. The difference in efficiency will become instantly clear.

People accustomed to using Western chisels with their softer, more plastic blades made from high-alloy high-scrap metal content steel with higgledy piggledy crystalline structure are actively taught to use the chisel like a crowbar to lever waste out of cuts. This is another type of “high-pressure cut” that damages the tool’s cutting edge at the microscopic level.

The sharpened screwdrivers sold as chisels in the West nowadays are relatively soft, can’t be made that sharp to begin with, and they dull significantly during the first few hammer strikes anyway, so most people can’t detect the edge degradation the chisel wiggle and prying create. Those who are satisfied with sharpened screwdrivers don’t buy our chisels so I have no advice for those poor benighted souls, only prayers: Namu Amida Butsu. But it is of little matter: they seldom have the sharpening and tool skills required to tell the difference anyway. Horse, meet water; Ah… not thirsty I see.

The Chisel Cha-Cha

Now that we have explained what not to do, let us examine what we should do instead.

Here is wisdom: A more efficient, more craftsman-like way to remove waste when cutting a joint is to stop striking the chisel with hammer during each cut just before the chisel binds, or just before waste clogs the joint, and then, without changing your grip on its handle or losing a beat in your cutting rhythm, flick your wrist forwards or backwards so the chisel blade flips the waste out of the joint you are cutting. And Voila! No time lost extracting a stuck blade or setting down and picking up your hammer; and no repositioning your grip on the chisel. And the cutting continues uninterrupted.

Its very much a crisp dance step performed by hammer and chisel with a rhythm something like: “chop, chop, flick, (reposition chisel for next cut)… chop, chop, flick, (reposition chisel for next cut) … chop chop flick.” With each “flick” bits of cleanly cut wood fly out of the joint. But please use your hands, not your feet.

Next let’s examine the nexus between hammer weight and avoiding the dreaded chisel wiggle.

The Dance of the Hammer and the Chisel

Cha Cha

As mentioned above, the way to avoid the chisel wiggle and instead dance the more efficient chisel cha-cha is to avoid banging the chisel into the cut too deeply/tightly. You need to stop hammering just before the blade binds in the cut, precisely and unconsciously controlling the depth to which your hammer drives your chisel, stopping just before the blade binds. Easy to say but difficult to accomplish if the hammer is too heavy. On the other hand, too light a hammer is also inefficient. Therefore, there is no one-size-fits-all-situations hammer weight.

A well-balanced, stable hammer with a handle that fits your hand/arm, and of a controllable weight makes it easier to develop and maintain this precise, unconscious control. Lots of factors are involved but the weight of the hammer/chisel combination is the most important one of the bunch.

How to determine the best weight? It changes with the work and tool and material and the nut holding the hammer so trial and error is the only practical solution. But generally, a hammer that feels a bit on the light side is best. And a good handle makes a world of difference. More on that in future posts, so stay tuned.


The following summarizes the points you should take away from this series of articles so far.

  1. Select a hammer weight that balances well with the width and weight of the chisel, the hardness of the wood you are cutting, your body, and the type of cuts you are making.
  2. The hammer should not be so heavy that you cannot precisely control the chisel’s depth of cut while maintaining an efficient cutting rhythm close to the natural frequency of the hand/arm/hammer assembly;
  3. Don’t drive the chisel so deeply into the wood that it binds forcing you to wiggle the chisel, or heaven forfend, set down your hammer to extract it;
  4. Use your sharp chisel for cutting wood, not prying out waste like a screwdriver. Instead, remove waste from the joint you are cutting by flicking your wrist without stopping, disrupting your cutting rhythm, or setting down your hammer.

There is nothing to stop you from using your hammer and chisel as a graceful but oh so violent dance team, so enjoy!

In the next installment in this tale of bold hammers and graceful chisels we will examine in more detail the rhythmical motions involved in doing chisel-work efficiently and the role of the hammer in that dance. No champagne or pretty girls but there just might be a song or two.


If you have questions or would like to learn more about our tools, please use the questions form located immediately below. Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google or incompetent facebook and so won’t sell, share, or profitably “misplace” your information.

Other Posts in this Series “Hammers to Use With Our Chisels”

Part 1 – Hammer Varieties

Part 2 – Hammer Faces

Part 3 – Hammer Weight

Part 4 – The Chisel Cha-Cha

Hammers to Use With Chisels Part 3 – Hammer Weight

“All that is gold does not glitter,

Not all those who wander are lost;

The old that is strong does not wither,

Deep roots are not reached by the frost.

From the ashes a fire shall be woken,

A light from the shadows shall spring;

Renewed shall be blade that was broken,

The crownless again shall be king.

J.R.R. Tolkien, The Fellowship of the Ring
Top: 375gm Yamakichi gennou head by Hiroki with new osage orange handle. Bottom: Ryoguchi-style gennou head by Kosaburo with a seasoned handle of the same osage orange. This same hammer was shown in Part 1 of this series when it was fresh and nuclear-flash yellow. With time and exposure to sunlight the color has changed to this pleasant brown. Thanks Matt for the OO!

In previous articles in this series about hammers to use with our chisels, we discussed the varieties of hammers and the types of faces suitable for using with our chisels. In this article we will examine not only hammer weights but other factors to help your chisel work go more efficiently.

Beater & Beatee

You can usually tell when a hammer is too light because the chisel or nail isn’t moved and the beater bounces off. But it’s the other end of the weight scale that causes problems so let us consider the case of too heavy hammers so we can bracket the Goldilocks weight: Not too heavy, not too light, but just right.

Some people like to use heavy hammers for striking chisels. 2~3-lb ox-killers are good for some jobs, but there are a few things you should consider before defaulting too such a heavy lump.

Is the impact force produced by a heavy hammer really necessary to drive a chisel? Not so much. But not everything we do must focus exclusively on efficiency: swinging a hammer is good exercise and it burns calories, something those with excess “ dignity,” such as your most humble and obedient servant, could use more of. However, maintaining one’s girlish figure is not adequate justification for using excessively heavy hammers in light of other factors we must also consider.

Besides the herculean strength of your mighty arm and the chisel’s durability, you should also consider the durability of your body. Swinging a hammer that is too heavy stresses muscles, tendons, and bone, stresses that can make the day long, the nights painful, and your work sloppy, if not now then certainly as you age. But if the weight of the head is a good balance with the work you are doing and you have a good handle on your hammer or gennou, things just go better. A word to the wise. We will look at this more in the final post in this series.

Let’s consider the movement of the hammer and the flow of forces that result starting at the beginning. Accelerating the hammer towards nail or chisel initially takes energy and creates stresses on muscles, tendons, bones and joints. Obviously, it is wise to keep these stresses within acceptable limits, especially if you need to repeat this movement hundreds or even thousands of times in a day. It should likewise be obvious that a hammer that is overly heavy makes limiting these stresses difficult.

Now that we have the hammer moving, let’s examine what happens when it stops as it strikes nail or chisel. Is wacking the nail or chisel as hard as possible the goal, or is the goal to drive the nail into the wood, or to motivate the chisel to cut wood an appropriate distance? If the latter, then there is a practical limit to the impact force required. In other words, driving the nail so deeply the wood is damaged, or the chisel so deeply it cuts all the way through, or even binds in the wood, is not useful, but is a waste of time and energy that damages our work product and our bodies, and that harms precision rather than improves it.

These forces and the positive and negative results are easier to control if the hammer’s weight is balanced with our bodies, the nail or chisel, and the wood. Heavier is seldom better.

Another factor to consider is the nature of the object the beater is to beat. Nails are one such beatee, but they don’t have feelings while chisels do, so I encourage you consider your chisel when selecting a hammer weight.

Our chisels are hand-made professional-grade tools intended to be used by craftsmen who demand the extra sharpness and cutting longevity only hard, fine-grained steel makes possible. Therefore they are not as tough as the soft, sharpened Chinese screwdrivers sold by the big corporations that amateurs are accustomed to using nowadays. Accordingly you should select a hammer weight that won’t damage the blades or splinter the handles of your fine chisels even if you must use them all day for days on end hard enough for the impact forces to make the handles hot. You may be as strong as John Henry, but a 2-lb hammer will destroy most any chisel given time and determination.

Weighty Matters

Of course, the harder the wood, the deeper the cut, the wider and heavier the chisel, the heavier the hammer needed. But what is an efficient hammer weight? Let’s look at some guidelines.

Oiirenomi & Mukomachinomi Chisels

For most commercially-available woods you are likely to cut with your oiirenomi chisels or mukomachinomi (mortise chisel), 180gm (6.5oz) is a good place to start when using narrower width chisels 18mm and less.

300gm (10.5oz) to 375gm (14oz) is probably good for wider chisels. BTW the standard carpenter’s hammer in Japan weighs 375gm (14oz), but this is too heavy for most precision work using oiirenomi in furniture, cabinets, and joinery work.

Atsunomi Chisels

For the heavier atsunomi chisels from 12 to 24mm in width, 375gm (14oz) is usually a good weight.

For wider atsunomi chisels, 675gm (24oz) to 750gm (26oz) is good. Maybe as heavy as 937gm (32oz) for motivating wide 48-54mm chisels when cutting hard woods if you have experience, strong wrists, and speed is not important. Yes, within limits, lighter weight hammers tend to accomplish more work quicker.

As Captain Barbossa explained the Pirate’s Code, these are “more what you’d call “guidelines” than actual rules.”

In future posts in this series we will examine factors such as how to use hammers and chisels efficiently, and how to avoid injuries.

We also have another series of posts in the batter box about making a handle for your hammer that fits your body and will work most efficiently for you. So let’s talk some more soon.


Related image
Harrrr. 180grams it is then matey!

If you have questions or would like to learn more about our tools, please use the questions form located immediately below. Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google or incompetent facebook and so won’t sell, share, or profitably “misplace” your information.

Other Posts in this Series:

Part 1 – Hammer Varieties

Part 2 – Hammer Faces

Part 3 – Hammer Weight

Part 4 – The Chisel Cha-Cha

Hammers to Use With Chisels Part 2 – Hammer Faces

Beware the Jabberwock, my son!
      The jaws that bite, the claws that catch!
Beware the Jubjub bird, and shun
      The frumious Bandersnatch!

Lewis Carroll
375gm gennou by Kosaburo with a black Persimmon handle resting on a Go board. The head is a classical style seldom seen nowadays.

This is the second post in our six-part series about hammers to use with our chisels. As with all the tool-related articles we publish, this one is based on past communications with, and in response to direct questions from, our Beloved Customers. We hope that not only our Beloved Customers (may the hair on their toes never fall out) but our Gentle Readers too may gain something from these articles.

We sell limited quantities of hand-forged professional-grade chisels to professionals who use them to please their customers and feed their families. We are tickled pink when amateurs purchase our products, but our target customer is the experienced professional woodworker. If you do your part our chisels will provide faithful, reliable service until, after many decades, nothing is left of the blade but a nub. But to make that possible, and to avoid smiles turning upside down, we insist our Beloved Customers use flat-faced hammers to motivate our chisels as a condition of our warranty. It’s that important, at least for the professional that uses his chisel even after the blade and handle become hot.

In the previous post in this series we looked at the Japanese gennou hammer with its two faces: one domed and the other flat. In this post we will examine these two styles of hammer faces in more detail. We will leave waffle-faces to the Belgians for now.

The Domed Hammer Face

Few people in industrialized countries outside of Japan have any experience with flat-faced hammers since manufacturers automatically grind a convex or domed striking face on their hammers. It’s simply what consumers are accustomed too. But I daresay few have ever considered the ramifications of the domed face.

1920x1080 Wallpaper hammer, nails, wood
An average-looking hammer. But is the shape of the domed face uniform, or is it skewampus or tilted? Is the centerpoint of the face and the center of mass of the head in-line? Good luck figuring it out.

A domed face on a hammer has some advantages. For instance, when one needs to “set” a nail with it’s head just below the flat surface of the piece of wood into which the nail is driven. But does a domed face help the hammer drive nails faster or straighter? Does it help reduce the ratio of bent nails to straight nails? Does it motivate chisels more efficiently? No, no and no.

Does this domed face look perfectly centered to you? Does it looks smooth? Can it be improved?

Another more questionable feature of the domed face (depending on your viewpoint) is that it makes it difficult to judge the accuracy of the alignment of the dome’s centerpoint in the face and with the centerline of the hammer head. Who, praytell, profits from this ambivalent construction? I’ll give you one guess, and it ain’t me or thee.

Indeed, if your working hammer tends to bend a lot of nails, I recommend you carefully examine its face with a square for center and uniformity. “Doh! (palm to forehead). No frikin wonder,” may well be your genteel reaction.

So why is a domed-face hammer a problem when striking Japanese chisels? Simply because a domed face tends to focus the impact forces on a relatively smaller area on the wooden handle than a flat-faced hammer does accelerating the wear and shortening the life of the handle.

In addition, and especially if you are skilled at hitting the handle dead-center a high percentage of the time, a domed face will actually cause the crown to try to jump off the handle and to become beaten up, sometimes even dangerously deformed, eventually damaging the handle.

The Flat Hammer Face

You can easily modify a decent-quality, properly-hardened hammer to have a flat face by simply abrading it with a grinder or sander.

Be sure you make the new face planar (flat) and truly square to the hammer’s centerline because a tilt to the left or right will make doing precise work inexplicably difficult and may lead to insanity. I once knew a frugal carpenter (read “cheap jackass”) who insisted on using a hammer with a skewampus face. The cumulative corrosion to his confidence caused his wits to wander into the weeds. A sad but common story, I fear.

If you are modifying a standard hammer with a standard handle, you may want to tilt the face’s plane a bit inwards towards the handle, but there is not adequate space in this post to discuss this modification in more detail.

Be especially careful to avoid overheating the hammer’s face while grinding/sanding it: too hot and the temper will be damaged softening the hammer’s face and ruining it. Seriously. Even a wooden chisel handle will eventually mushroom a steel hammer that has lost its temper. Here’s a guideline: If the hammer’s face becomes becomes too hot to touch with your bare finger, the temper is at serious risk.

Finally, once the face is as flat and square and smooth as you can make it with your grinder or sander, be sure to polish the face because a smooth face wears out the chisel handle slower. A final polish with 320 grit W/D sandpaper is adequate. We polish ours even finer on sharpening stones. Overkill? Yup. Why bother? Because we like purty hammers. Don’t worry, the polish won’t make the hammer face slippery.

By the way, once you have your flat-face hammer, try driving nails with it. You will find it works a lot better for everything except setting nailheads below the board’s face. A nailset works better for that job anyway.

We hope our Beloved Customers will take this article to heart for the sake of their chisels.


In this post we reviewed two types of hammer faces: domed and flat. We also considered the advantages and disadvantages of each, and explained why a flat face is best for beating on Japanese chisels, and gave an example of the brutish damage a domed face can inflict on a poor innocent chisel. Like me, some of you may have shed a tear at the sight, but I bid you take heart because we also instructed you in how to convert a common domed-face hammer of any sort to a more genteel and polished flat-faced hammer at no cost, one that will also drive nails better. O frabjous day! Callooh! Callay!

To motivate chisels efficiently, the hammer must not only have a flat face, but it must be of the appropriate weight. Of course, the harder the wood, the deeper the cut, the wider and heavier the chisel, the heavier the hammer needed. But what is an efficient hammer weight? We will examine some options in the next post in this series. Please stay tuned, my beamish boys.


A hand-forged square gennou head by Hiroki with a handle made from a traditional Japanese handle wood called “Kamatsu” (Pourthiaea villosa) meaning “sickle handle, also called “Ushikoroshi (“cow killer”). Despite the appearance, the head is one-piece of uniform steel, not a jigane body with forge-welded steel faces. BTW, if someone tells you that hammers with forge-welded faces are superior, direct them to the closest legal marijuana dispensary so they can maintain their waking psychotic dreams.

If you have questions or would like to learn more about our tools, please use the questions form located immediately below. Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google or incompetent facebook and so won’t sell, share, or profitably “misplace” your information.

Other Posts in this Series:

Part 1 – Hammer Varieties

Part 2 – Hammer Faces

Part 3 – Hammer Weight

Part 4 – The Chisel Cha-Cha

Hammers to Use With Chisels Part 1 – Hammer Varieties

Yet such is oft the course of deeds that move the wheels of the world: small hands do them because they must, while the eyes of the great are elsewhere.

A modern-style 750gm gennou head hand-forged by Kosaburo, hung with a black persimmon handle. I purchased this high-quality head over 33 years ago. An heirloom tool and a good buddy.

This is the first article in a six-part series that condenses the advice we have given to our Beloved Customers over the years regarding the hammers they should use with our chisels. While some of this information is relevant to our warranty, all of it is relevant to how well our chisels will perform and the pleasure our Beloved Customers will enjoy using them.

In this first part we will focus on the varieties of hammers we recommend. Subsequent articles in this series will focus on appropriate hammer weights and faces, how to use a chisel efficiently, the “chisel cha-cha,” the importance of rhythm, as well as a discussion about health and hammers. There may even be a song or two to hum along with. Helluvalot better than a performance of Cats, and cheaper too.

In the future we will present several different series, one with more details about hammer heads, and another explaining why and describing how to make a handle for a Japanese gennou hammer (or any hammer for that matter), with scaled reference drawings. We will of course provide the entire contents of these articles in a single wiggling bundle to our Beloved Customers that purchase one of our gennou heads. Yes, there are more perks to being a Beloved Customer than simple toe-curling joy (ツ)。It’s a cunning plan, you see.

Hammer Materials

30mm Atsunomi by Kiyotada

We sell tatakinomi chisels such as oiirenomi, mukomachinomi (mortise chisels), or atsunomi all designed to be motivated by the most efficient method available, namely a steel hammer swung by human hand and arm. I won’t debate the pros/cons of steel hammers versus wooden mallets versus plastic mallets versus brass hammers versus unobtanium-platinum alloy hammers in this post because the physics are as obvious as a lemur in a lingerie shop (they’re a bit hairy, they jump and climb all over the displays and bras don’t quite fit them right) beyond noting that a hardened steel hammer imparts more energy to a chisel in a more easily focused and controllable manner than any other type of beater considering the economics of both initial cost and repair/replacement cost. Some may disagree; A mind is a terrible thing to taste.

The advantages of the steel hammer are quite obvious, even without doing energy calculations, but are there any disadvantages? Mochiron (Japanese for “of course”).

Steel hammers can concentrate so much energy on a tool handle so efficiently and so quickly that they may eventually destroy the handles of the sharpened screwdrivers sold as chisels nowadays in Western countries due to a faulty design detail. It’s this silly design flaw most modern Western chisels share that motivates people to use softer, fatter, energy wasting mallets made of wood, plastic or rawhide. So sad. 

An obvious solution is to use a steel hammer of a reasonable weight along with intelligent technique to effectively keep the energy imparted to the chisel within acceptable limits. But this may not be enough if the chisel design is weak.

Ooh ooh! I got’n idea. Why not design and manufacture a chisel that a steel hammer won’t destroy as a matter of course? Wow! Such an innovation would be right up there with the rumors I’ve heard of buggies that move without horses. Imagine that…

Fortunately, the tataki nomi chisels we sell are professional tools designed to be struck by steel hammers so they need not be coddled. They have a mild steel kuchigane (coned ferrule) fitted where the handle meets the blade, and a mild-steel hoop, or crown seated at the butt end of the handle. When properly fitted to a dense, straight-grained Japanese oak handle, this steel furniture does a great job of protecting the handle from splitting or breaking.

However, along with the handle, these parts do need to be setup properly to ensure they continue to protect the handle for a long time. We have provided clear instructions for how to perform this setup job here.

So, please use a hardened steel hammer with our chisels.

But there is more to hammers than just materials, so let’s continue onto the next subject.

Japanese Hammer Types

A Kosaburo head with a brand-new nuclear-flash colored Osage Orange handle

The traditional hammer used in Eastern Japan for striking chisels and general carpentry work is called a “gennou” pronounced “ghen-noh.”

Janus Coin

The gennou common to Eastern Japan is a simple symmetrical cylinder of one sort or another with a flat face on one end and a domed face on the other, often called the “ryoguchi gennou,” or the “Janus Hammer” by those with a classical education. No claws, no pointy tail. The flat face is used for striking chisels and pounding nails. The domed face is used for something called “kigoroshi” and for the last stroke when setting nails. It’s a handy tool and more stable in the swing than a claw hammer. It’s a matter of physics.

Japanese carpenters use a specialized nail bar for pulling nails effectively increasing the lifespan of their hammer handles, so claws are not necessary.

3 gennou heads. The far left head is a simple economy head. The center head is a higher-grade head slightly flared towards the ends. The far right head is an entirely hand-forged classical “swollen eye” tool by Kosaburo.

The Yamakichi style gennou head (see photo below) is another variety popular primarily in Western Japan. The tail is not pointy but rather a small square face that is useful for starting small nails and for “ tapping out” plane blades. The face typically has a slight curvature which is helpful for setting nails, but not enough to damage a chisel. The moment of inertia is less than the symmetrical gennou head so it is not as stable in the swing, but it is still a fine head.

A “Yamakichi” style head by Hiroki with a mellowed Osage Orange handle

The pictures below are of a gennou head called “Funate,” which translates to “boat hand.” I have heard it originated with ship carpenters, but am uncertain. The tail end is a small square as you can see from the photo, and is handy for setting nails. It makes a great finish hammer, but as a hammer for striking gennou it never appealed to me. But there are plenty of craftsmen that love this hammer.

a Funate gennou with a bubinga handle

Any of these hammers will do the job: it’s all personal preference.

Western Hammer Types

The purpose of this article is is not to suggest that our Beloved Customers must use a Japanese hammer when beating on our chisels. In fact, nearly any variety of quality steel hammer can be easily modified to do the job satisfactorily, including claw hammers, engineer’s hammers, or even ball peen hammers, so it isn’t necessary to buy a special hammer.

Please note that the closer the hammer’s center of mass is aligned with the center of the striking face, and the higher the hammer’s moment of inertia, the better. A cylindrical head is the closest to ideal from a physics viewpoint.

We’ll talk about the governing physics of hammers in future posts for those Gentle Readers that enjoy math.

In the next post in this series we will examine the type of face a hammer used to strike our chisels should have. Please come back and bring your lingerie-loving lemur friends. A Brazilian body wax is not required.


If you have questions or would like to learn more about our tools, please use the questions form located immediately below. Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google or incompetent facebook and so won’t sell, share, or profitably “misplace” your information.

Other Posts in this Series “Hammers to Use With Our Chisels”

Part 1 – Hammer Varieties

Part 2 – Hammer Faces

Part 3 – Hammer Weight

Part 4 – The Chisel Cha-Cha