Road Trip; Tsunesaburo plane makers.

Hi again Faithful reader.

(Sorry for the delay of the waterstone review, I hope after reading this you’ll understand I have a few dozen things to do right now, all important. Especially this one…)

On Wednesday my co-pilot and myself took a road trip into Miki city, Hyogo prefecture to meet (see? I’d already met them myself…) the folks at Tsunesaburo, makers of fine Japanese planes for 3 generations now. I’ll cut to the point here, they are very likely the best known and most prolific plane maker in Japan today, and earned that position quite a while ago by focusing on what the customer wants from their plane rather than what might be ‘traditonal’ or ‘correct’. As a result, they are still making planes as fast as they can and sending on their way to their new owners while many others have sadly been lost due to the economic realities of a world where the power planer and sander exist in competition with the hand plane, and doing the same work with less physical effort, but acceptable, if inferior results.

During a recent trip to a tool makers show in Miki I visited, there were several booths that were inundated with people looking, trying and buying. To be specific, there were two that were more heavily trafficked that any other, they were Mitsukawa (saw makers) and Tsunesaburo. And this was in a room with all the major Miki city tool makers in attendance.

I suppose it helped that 100,000 people visit that show every year, but even so, the number of people crowding around their booths was astonishing. I was only able to quickly meet the fellow now running the day to day operations at Tsunesaburo, Mr. Touru Uozumi, whose picture you’ll find in the top right corner of Tsunesaburo’s home page. My first impression was of a nice enough fellow who was just too busy to talk.

Flash forward to Wednesday when we arrived, and my first impression was confirmed, with interest.

Contrary to what one might think with three generations of tool makers having plied their trade in the same location, and being so highly respected in the trade they are in, Mr. Uozumi was warm and welcoming and. Like an old friend within a few scant minutes. Even my co-pilot was pleased to find such a nice person on the other end of several emails and telephone calls. This is becoming a common trend in my dealings with Japanese tool makers, not at all like the reputation (both real and imagined) that is portrayed all too commonly of a wizened old man, hands like bunched walnuts and a cranky disposition. They do exist, but I’ve not been introduced to one of them. Yet…

I did take along a list of difficulties that plague the more wide spread adoption of Japanese planes outside of Japan, and to my surprise, my list was replicated by Mr. Uozumi. He is aware of the stigma attached to kanna, and over the course of the all too short time I was there, proceeded to break them down, one by one. But more about that later.

First, a little tour of the operations at Tsunesaburo.

There is a small meeting room off to one side where the history of Tsunesaburo is laid out, and gives an idea of the effort is given to making sure their planes are so popular. Note the lengths of tool steel standing up there, showing just how many steels (hagane) are actually used to make the blades, and they all behave very differently, depending on what you might want from your blade. I don’t believe any other plane blade maker offers so many choices. Below the edge steels are the different choices of soft backing steels and irons (jigane), again, all behaving slightly differently depending on what the end user desires from their plane. Interesting to note that all of the iron present is imported, and recycled after having served a full life as something else before. Present are sections of ship’s chain, ship’s anchor, railway track and structural sections.

At the time these items were serving their original purpose 100-150 years ago, Japan had little capacity for producing anything more than small items from iron or steel. Much of this heavy section material was produced in England and shipped to Japan already finished and ready for assembly as a rail track (with hard steel wearing surfaces, note the rail is similar top and bottom so it can be flipped over, doubling it’s life), bridge or building. As the material is of an age where wrought iron was the material of choice for these heavy duty applications, they all have a similar desirability for tool backing material in that they are easy to grind, easy abraded by sharpening media and resistant to rust all while being easy to forge and very strong. Currently, wrought iron such as this is no longer used on such a large scale, so any old wrought iron that is removed from service is rapidly gobbled up by tool makers such as Tsunesaburo. The supply is finite, and rapidly diminishing.

A gratuitous picture of a very wide plane. The explanation for this is quite simple, a wider plane works faster. While these larger planes look very much like some sort of gimmick and never used, the fact is that they are still made and still used especially by temple and shrine builders working with larger timbers. Instead of taking several passes on a board or beam, one pass is enough and produces no tell-tale track marks. So not an everyday kind of tool, but useful for the purpose it is intended for.

A picture of my co-pilot displaying an example of a shaving of, if I recall correctly, 5 microns thick. That makes it half the thickness of plastic food wrap and to convert to inches, 0.000196 “. I don’t even know how you measure something so thin, but there it was, completely intact and obviously not too rare as we were allowed to touch it. Granted, we treated it like it was some fabled artefact which I’d think pretty much everyone who holds it does the same. To give you an idea, it looked like a piece of ladies silk stocking, far more delicate in appearance than even tissue paper.

Outside the office’s front door is an old anchor. It’s been left in its original shape, but I just know its days are numbered until it will be hacked up and made into plane blades. How many days, only time will tell. It’s an interesting and impressive sight all the same. And those stories of there being big, ugly chunks of old wrought iron outside these kinds of workshop is true. There’s the picture.

Moving along we entered a small, separate building located at the very front of the office/factory area. Inside is the original forge where Tsunesaburo started, preserved and still in good working order. As the New Year is still very new, the decorations used to bring in the New Year are still up and fresh. It may appear to be some kind of useless affectation and somewhat run down, but appearances are deceiving. I’ll admit the first thing I thought was that it was simply an old outbuilding ready fall down with a stiff breeze (they are a common sight in Japan), until I closed the door. It felt like a new door, but obviously was not new at all. It was a surprise, as was the inside as you can see in the photograph.

(Just as a side note, this forge was shown in a historical television drama a few years ago, as it would have been used during the time period the drama was set in. Mr. Uozumi played the part of the bladesmith himself, and said the experience was interesting, enjoyable but also a little frustrating. It is also the very same forge shown in Mr. Toshio Odate’s ‘Japanese Woodworking Tools on pages 142-143)

Mr. Uozumi showing how the forge was operated, the smith would work the large, box bellows with the left foot, and tend to the fire while seated. From there, the very low anvil was just off to the right of the fire, where one or more hammer-swinger types would do the hard work of getting sections of metal from a not very useful shape into something more closely resembling a plane blade.

The large box bellows is, as expected, in good working order. Simple flap valves on either side of the piston allow air in and out, and a manifold combines the air from the two outlets into one. Rather simple to make being mostly wood and very effective. While the box is large, the smith might only use a very small stroke to supply the air required so making it larger means that more air can be moved for a similar amount of effort and if a lot of air is required, simply make longer strokes of the piston.

Here is a view from the driver’s seat. You may notice the large pot on top of the fire and wonder what it is for. Making blades is hard work, and all involved work up an appetite, so that’s where the rice for lunch is cooked! Identical pots are still used today over open fires for boiling rice on a large scale.

Please disregard this picture. It’s just me doing as I am told for the camera…

(Happy now? You know what I look like. Sheesh!)

Leaving out the back door of the old, original forge, we went into the current incarnation of it, where the wrought iron sections are forged into billets, the hard steel for the blade’s edge forge welded to the billets of iron or soft steel and the basic shape of the blade is made. This large air hammer is the main workhorse, and also features on the front page of Tsunesaburo’s print catalog. Note the standard style anvil and fan, even in winter. While the big hammer (and it is BIG) does most of the hard work, there’s no escaping the fact that this forging is still hot and difficult work.

To the left of the large hammer is the coal forge, where some of the blades are heating to forging temperature (approx. 1300⁰C/2350⁰F) and to the right, the gas forge. Whatever the jigane/hagane need for heat, it’s right there.

Off to the far right is a smaller air hammer and cutting press, and lastly a die press for cutting the blades to general shape. Maybe not as romantic as someone banging on an anvil all day, but effective all the same.

And here we have a piece of wrought iron, forged into a billet ready to be turned into a blade in the near future. You may wonder why anyone might go to so much trouble to collect old scrap iron, chop it up into smaller pieces, heat and hammer it into billets then welding on a small sliver of blade steel just to make a plane blade, and I could explain it now but will hold off until another time. You may not believe it now, but I for one am very thankful that tool makers like Tsunesaburo still go to all the trouble of making blades in this convoluted manner.

A last look at where everything is before moving on.

Here we have a pile of iron section in its ‘as found’ state, yet to be drawn out into a billet as well as some steel of more recent manufacture already in a usable shape. Along side, Mr Uozumi showing all the different tool steels ready to be chopped up as needed.

This box contraption is one of the key items that allows Tsunesaburo to offer so many different combinations of soft backing and hard edge and do it all quickly. It’s a furnace used for quickly relieving the stress that the forging/welding process introduces to the blades. Without this piece of equipment, the blades are usually left to cool slowly and then rested for several weeks to allow them to settle down, ready for the next stage of their journey to become a completed blade. The chisels made at Koyamaichi are also rested at this point, which explains the ‘up to 6 weeks’ processing time on orders, just in case a chisel needs to made to fill the order. Most of the time, the chisel is just taking a little rest after being incinerated and having the living daylights beaten out of it.

If the blade is not allowed to rest (or stress relieved) the resulting iron will not look any different, and sometimes you may not notice any difference until it comes time to actually use the tool, whereupon the residual stress from the heating and hammering typically manifests itself as a very brittle edge that can and will chip, crack or break off. This manufacturing defect can take many years to cure at room temperature, a month in a medium that allows the blade to cool slowly or hours in a special kiln like this one in the picture.

Trust me, you don’t want blades that haven’t had their beauty sleep. If you’ve ever had a Japanese tool that is brittle, it’s likely because it’s been denied it’s R&R and would greatly benefit from being stuck somewhere dry, warm and cozy for a year or three. Maybe…

Here, blades that have been relieved of stress and awaiting further processing.

And here, the row of grinders. No belt guards, and only rudimentary wheel covers. OHSA isn’t really big in Japan…

I must mention that as we walked through, I was somewhat saddened that all was stationary, as though things were very quiet. Stupid me didn’t realize that it was lunch time…

On the other side of the room, mechanical hammers of the leaf spring type. You might wonder how these work. Looking at the top, note the crank wheel attached to a connecting rod. The other end of the rod attached the middle of a leaf spring. Either end of the leaf spring attached by flexible ‘belt’ to a hammer shaft sliding in a bearing. Quite simple, very common and have the nice feature that you can put something in there that needs hitting, but the size of it doesn’t matter. Something large will not be pulverized; something small will still be hit. This row of hammers is used for any cold hammering required, typically shaping and some decoration. Beats swinging a hammer!

This odd looking contraption is a press. The large axle and wheel assembly above turns by way of an electric motor but originally was probably propelled by line shaft running the length of whatever building it was in, with power supplied by leather belt. A lever down on the right side (or occasionally a pedal) moved up or down will move the axle/wheel assembly so that the larger wheel will turn the centre wheel which is connected to the large acme thread, turning this then moves the die fitted in the press up or down. Seems like an overly complicated way to get things done, and an artifact of a bygone era. These are, again very popular and the reason is control. You can move the die quickly or slowly, and when it makes contact you can apply just a gentle push or a bucketload by how much pressure is applied to the lever. Besides which, these presses are relatively common and reliable so there’s no question as to why they are popular.

And here is the heat treating station. Blades get heated, dunked in the water then deep fried to temper. For those steels that require a different temperature range to that produced by the oil bath, a molten lead bath is used instead. Again, maybe not as romantic as watching for the colours and catching them at the right instant, but reliable and consistent.

Last picture showing the general lay out of the blade finishing area. It looks like a large area and a lot of machines, which it is, but the machines are usually left set up for a specific operation rather than used then adjusted frequently. Again, efficiency is the name of the game.

This last machine was a surprise, a surface grinder. I couldn’t think of anything this would be used for until it was explained that this has one specific job, and that’s grinding one special type of blade’s back correctly. It was a surprise to see it there, but it definitely earns its keep.

And that’s the end of our Tsunesaburo factory tour. The plane bodies (dai, pronounced die) are made off site by specialist dai makers. We didn’t go and see them.

At this point, there are no more pictures. We all trotted off for lunch, then came back and talked for several hours. Simply put, there was nothing terribly interesting to actually take pictures of, but what we talked about was very interesting. I can honestly say that I learned more in 2 hours there than I have learned in 2 hours ever before. Almost every concern I had about Japanese planes was either shown to be misleading, slightly off course or just plain wrong. There are some things that just can’t be changed, but at the same time, there’s a lot that we can change, and do plan to.

But those details are for another time, another place.

There will be more information coming, a lot more information coming. To bring around this abundance of information both Mr. Uozomi, and by extension Tsunesaburo along with myself will work hard to rectify the wrongs purported previously, demystify ‘kanna‘ and show that there’s really nothing to be afraid of. I won’t be getting rid of my iron planes any time soon, but I have serious doubts as to whether I’ll ever buy another one again.

After all, it’s not every day you make a new friend who just happens to be responsible for making some of the best user planes on the planet, is it?

I hope you’ve enjoyed reading and seeing how things work at Tsunesaburo plane makers, and I hope to be able to show you some other places where these tools are actually made and the people who make them very soon.

Thanks for reading,

Stu.

P.S. You might be wondering why I keep referring to Mr. Uozumi as “Mr. Uozumi”. That’s because it’s his real name. The name of the company, Tsunesaburo, is (I believe) derived from Mr. Uozumi’s grandfather, the man who started the company. His name was Mr. Saburo Uozumi. No prizes for guessing what part of his name he gave to the company name. The ‘Tsune’ translates literally as ‘always’, so if you can let your imagination wander a little, it’s actually quite a catchy name and quite the marketing strategy.

Appears to have worked very well too.

6 comments to Road Trip; Tsunesaburo plane makers.

  • Mike Skogen

    Thanks a bunch Stu………….Skogs

  • Looney Toon

    Great entry and an eye opener, especially the simplicity of the operation and the no frills shop.

    Nice pose there mate. :)

  • Stu,
    Fascinating. Thanks for presenting this and I’ll be looking forward to learning more about Japanese planes from your writings.
    Rob

  • Dave Holmes

    Stu,

    Thanks for the tour and the photos. I feel I just met you via the self portrait.

    Look forward to learning more and perhaps purchasing a few dai’s.

    Dave

  • David Weaver

    So…when will we be seeing laminated 3/16th inch hitachi steel plane irons for western planes?

    :)

  • David Weaver

    er… make that 1/8ths maybe …

    .. and not when will we be seeing them so much, as when will we be seeing them on your website :p