NAUTICAL RESEARCH JOURNAL 163

Tosa Wasen: A Traditional JapaneseTwenty-Foot Fishing Boat

. . . . .by Clare Hess

Figure 1. Mr. Shibafuji standing next to a Tosa wasen at Kansu-hori Harbor, Urado Bay, Kochi City in 2008. He apprenticed withboatbuilder Masaru Hiromitsu, who built the boat in 2006. Mr. Hiromitsu had built wasen for 60 years when he passed away in2014. Courtesy of Mr. Shibafuji.

Introduction

Those Guild members who werefortunate enough to attend the confer-ence at Mystic in October 2016 had theopportunity to listen to a fascinatingtalk given by boat builder DouglasBrooks about Japanese wooden boat-building, and his five apprenticeshipswith master boat builders in Japan.

I was already familiar with

Brooks’s work, having been in touchwith him over the past couple of yearsregarding the replicas built of traditionalJapanese coastal transports such asNaniwa Maru and Michinoku Maru. Fol-lowing his work, I also began to learnabout traditional small Japanese boats,which led me down an entirely new pathas a ship modeler.

I had already discovered theJapanese wooden ship model kit manu-facturer, Woody Joe, and built a few of

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the company’s kits, when I discovered arather obscure, but very interesting look-ing kit of a traditional twenty-footJapanese fishing boat. I did not knowmuch about it other than seeing a fewphotographs on the Internet, and it tookme many months before I discovered themanufacturer. It was sometime laterthat I was able to determine that the kitwas in production and available for pur-chase.

The boat is called the Tosa wasen,which literally means traditional Japan-ese-style boat from the Tosa region. Themanufacturer of the kit is a companycalled Thermal Studio, and is a maker oflarge model glider kits. The fact that Ihad a hard time finding the Tosa wasenkit was partly due to the fact that it wasa special sideline product of the com-pany, and, at the time there was no men-tion of the kit on their website.

The only reason I was able to pur-chase the kit was because I stumbledupon it while perusing Amazon-Japan, asite that is not easy to navigate if youcannot read Japanese. Fortunately, Iknow just enough of the language andhave enough computer skills to be ableto type Japanese text and to use a mix ofoptical character recognition, onlinetranslation, and the Chinese characterrecognition feature built-in to my com-puter to get by (The Japanese languageuses Chinese characters that the Japan-ese call kanji). I purchased my kit fromthe Amazon-Japan seller, and since theydid not offer international shipping, Ihad a friend in Japan act as a shippingagent, forwarding the package to me. Ihave since contacted the manufacturerby email and we began a discussionabout the kit, which was still being pro-duced, and how those of us outside of

Figure 2. Douglas Brooks and Mr. Masaki Tanimura of Thermal Studio at a lunch meeting when Mr. Brooks was working on a boat-building project in Takamatsu in 2013. Courtesy of Mr. Tanimura.

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Japan could purchase it. I will providethe purchase details at the end of this ar-ticle.

The company that makes the kitis run by Masaki Tanimura, who createdthe product out of his desire to producea kit of a traditional Japanese woodenboat that is built from the same materi-als used to construct the actual boats.While some ship modelers may balk atthe idea of using woods not best suitedto model building, it is a practice com-mon among Japanese boat builders whocreate models of their own boats. And,though the grain and figuring of thewood may be out of scale, the color is

right, and the Japanese woods used arevery aromatic, giving the builder an un-usual sense of connection to the subject.

The kit was developed under thesupervision of the Tosa Wasen Tomo noKai, or the Tosa Traditional WoodenBoat Society. The man who made theoriginal drawings for the manufactureris Toshihiko Shibafuji, who manages thesociety ’s Facebook page, and who waskind enough to reach out to me after themanufacturer made a Facebook postabout our email conversation. Mr. Shiba-fuji had studied traditional boat buildingwith master boat builder Masaru Hi-romitsu in the Tosa area. I discovered,

Figure 3. The instructions are in Japanese, but they are well illustrated and the steps involved are clear. There are a few spotsthat might be a bit confusing, but a careful study of the drawings will usually clear things up. All images by the author unless oth-erwise indicated.

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interestingly enough, that Mr. Shibafujiand boat builder Douglas Brooks wereacquaintances, and that Mr. Tanimuraand Mr. Brooks had met a few years ago.The world, it seems, is shrinking everyday, at least in terms of Japanese tradi-tional boat building and model making.

About the Tosa Wasen

The Tosa wasen is a traditional twenty-foot boat that was used by fishermanfrom the Tosa region on the south sideof Shikoku, one of Japan’s four main is-lands. Typically, these boats carried oneor two fishermen, who fished using

bamboo poles. The boat is made prima-rily of sugi, or Japanese cedar, withmajor structural pieces made from hi-noki, or Japanese cypress.

The hull design is of a style simi-lar to most Japanese traditional boats inthat it features wide, relatively thickboards, making up a five-sided hull con-sisting of a bottom board, two garboardplanks and two sheer planks. Unlikemost western boats, where a frame isfirst built and planks are fastened to it,traditional Japanese boats are mostlyframeless, and planks are edge-fastenedwith large iron nails. Typically, thesehulls are supported by athwartship

Figure 4. Plans are printed in Japanese, but mostly show the part identifier labels. The numbers shown are millimeter dimensions.Though a few items are mention by name, for the most part, the builder who doesn’t know any Japanese is not missing anything.

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beams, and, sometimes, by a few keyframes, both of which are usually addedonly after the hull planking is nailedinto place.

The inside of the Tosa wasen isdecked over with small, removable pan-els, creating easily accessible storagecompartments underneath. Being builtfor fishing, there is a pair of live wells inthe center of the boat, with the largerused to hold the catch and the smallerused to hold bait.

At the stern is a heavy beam witha pivot base located on the port side forthe single, long sculling oar, which iscalled a ro. This oar is quite long andfeatures an off-set handle and rope lan-yard that, together, cause the oar to self-feather. When travelling longer

distances, the fisherman operating theboat might stand and use both hands onthe sculling oar. But these small boatswere typically used for pole fishing, andthe Tosa fishermen commonly used aone-handed sculling technique, allowingthem to sit in their boat and hold theirfishing pole in one hand, while operatingthe oar with the other. In modern times,while the sculling oar is still used whilefishing, an outboard motor is often usedfor faster travel to and from the fishinggrounds.

The Kit

The Tosa wasen kit is a 1:10-scalemodel that makes heavy use of laser-cut

Figure 5. The kit’s laser-cut parts sheets are well labeled using Japanese characters as part identifiers. When cutting the partsfrom the sheets, the dark lines of the cedar wood are much denser than the lighter areas, so the laser did not fully cut throughsome of the dark lines.

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Figure 6. A temporary former is used in the kit to aid in the alignment of stem and transom, the positioning the floor frames, andto provide rigidity to the model while in the early stages of construction. On real Tosa wasen, these floor frames are only addedafter the hull planks are attached.

Figure 7. An alignment template provides the proper angle for bow and stern storage compartments. This is very similar to dou-ble-ended templates I’ve seen used in traditional Japanese boatbuilding for the setting of key angles.

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parts. Being patterned after a twenty-foot boat, the completed model is abouttwo feet long. The parts are all well la-beled, using Japanese characters as partidentifiers. Western manufacturersmight label parts “AB”, “AC”, “AD”, andso on, but in Japanese characters, thesewill look more like セイ , セロ , セハ ,Those not familiar with written Japan-ese may get confused by the similarity inappearance of some of the characters, soit may take a little extra care to properlyidentify some parts. But knowledge ofthe characters is really not necessary, asthey do not actually spell anything here.

Because of the nature of some ofthe parts, the identifying labels are

sometimes etched on a visible part of themodel. Sanding them off is possible, butthe etching is deep enough that some la-bels are difficult to remove. In a coupleof instances, it seemed to be better tosimply leave the labels in place. Mostpeople seeing these will not know whatthe Japanese characters represent any-way.

Laser etching is also used to goodeffect in this kit—simulated mortises areetched into the surface of the planks, asare lines for the alignment or some partsor to indicate the edge of an area to bebeveled by the modeler. A unique featureof this kit can be seen if you flip over thelaser-cut sheets. You will see that, on

Figure 8. Creating a nice, graceful, fair curve comes before the building of the supporting structure. This is a common theme inJapanese traditional boatbuilding that took a little time to understand. At first, I was positive I must have been missing somethingimportant in the instructions.

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some of the sheets, there is etching onthe back as well as on the front. Thiswould require the manufacturer to runthe sheet through the laser cutter twice,with the position of the sheet perfectlyregistered for the second pass. This isthe first time I have seen this done on awooden ship model kit.

The instructions in this ThermalStudio kit are well illustrated. And,while they are written entirely in Japan-ese, for the most part, the illustrationsare clear enough to follow without texttranslation, similar in many ways to theinstructions by the Japanese woodenmodel kit manufacturer Woody Joe.

An unusual, but very handy inclu-sion in this kit is a simple sanding block

and some very nice quality narrowmasking tape. Also, included are somecyanoacrylate glue applicator tips. Ithink the idea here is to stress applyingonly very thin beads of glue when build-ing this kit.

Working with the Kit

Construction seemed to mostlyfollow actual traditional practices. Eventhe joint where the floorboard angles up-wards near the stern is created by par-tially cutting through the floorboard andthen physically pulling the after portionof the board upwards, a method thatmimics a technique used in real wasenconstruction. One obvious simplifica-

Figure 9. The basic structure of the traditional Japanese boat makes use of beams that are added after the planks are fastenedtogether and used to support the deck.

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Figure 10. The deck boards are all unique, shown here completed and in place. The boards in the kit come oversized, requiringthe builder to sand them to fit. It was extremely easy to over-sand the soft wood.

Figure 11. I found this feature interesting and assumed it must have been a live well. An email to Mr. Shibafuji confirmed that thiswas in fact a live well with the larger compartment for the catch and the smaller one for bait.

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tion is the use of a temporary mold thathelps to locate and properly positionfloor timbers, the transom piece andstem. This also gives the model a littlemore rigidity when working on it in theearly stages of construction, and, with-out it, the build would probably havebeen a lot harder.

One downside: as mentioned ear-lier, the wood used in the kit is primarilyJapanese cedar. This wood has a lightreddish-brown color and is streaked withdarker figuring lines. The wood is prettysoft, so sanding is a bit tricky, and it is

Figure 12. A small variety of included accessories added some life to the model. The larger structures are simple, low woodenseats. What looks like a dustpan is a bailer. The remaining item is a small wooden hand-paddle called a Te-Kaki.

Figure 13. I loved the details of the boat’s anchor. The ropeis fasten where the wooden cross-piece fits through the metalanchor. The rope is then attached to the eye of the anchorwith a separate piece of rope.

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easy to take off too much wood. Also,while the wood is soft, the dark figuringlines are much harder. So, if it is neces-sary to cut the wood, the different den-sities within the wood will cause a knifeto deflect very easily. It can be cut, butit is tricky, and I do not know that re-placement parts are feasible or whatThermal Studio’s policy is regardingthem. So, it is necessary to be extra care-ful.

Construction Difficulties

There were a couple of things thattripped me up during the build. The firstof these was the covers for the storagecompartments at each end of the boat.These were fitted into place after mostof the model was completed, using a pairof wooden tweezers that you build usingparts included in the kit. It would havebeen simpler to build these compart-

ment covers at the time the compart-ments were being built. But I believe theorder of construction here was meant tofollow that of the real boat.

Another issue was with the build-ing of the rails, called sekidai in Japan-ese. It took me a while to getcomfortable with the idea that the shapeof the rail is not defined by the support-ing pieces, since most of those are addedafter the fact, but by the eye and experi-ence of the builder. The plans show theshape of the rail but, in a model withpre-cut parts, I developed an expectationthat the parts would be made to fit,which they were not. The rail piecesthemselves were overly long, and thelaser-cut pieces that fit underneath wereoverly wide. But the over sizing allowsfor some variation in the build.

Probably the most difficult time Ihad was in shaping of the deck boards.Since each one was unique, and pre-cut

Figure 11. The sculling oar was a treasure of this kit. I have built other kits of Japanese boats with sculling oars, but this was themost detailed. The plan drawings showed the changing cross-section of the blade, which was exactly as described in the book byDouglas Brooks, illustrating the authenticity of this model.

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to oversized dimensions to allow forbuild variations, they required carefulsanding and fitting. The main issue herewas simply the softness of the Japanesecedar and my desire to make use of thekit’s included sanding block. It was ex-tremely easy to sand the wood toomuch, and once that happened, therewas not much that could be done exceptto take some of the left over scrap woodfrom the laser cut sheets and fashionnew pieces. There is enough scrap to fixa few instances of over sanding, but, ifthat runs out, it is hard to match withdomestically-available material. WhileJapanese cedar is an inexpensive wood inJapan, it is impossible to find in theUnited States.

Interesting Discoveries

One of the things I have alwaysloved in building model kits, even theplastic ones I built in my youth, is thatone always ends up learning somethinginteresting about what one is building.In the case of the Tosa wasen, there wasactually quite a bit of that. But, therewere a couple things in particular thatgave me an “Aha!” moment.

One of these was the deck boardsand the pattern that is drawn on thetops of them. These boards serve notonly as a floor to stand or sit upon, butalso as a cover for the storage spacesunder the deck. They are easily remov-able and some have a finger hole tomake it easy to reach through and pullup the boards. Interestingly enough,these deck boards are not uniformly con-structed. They are instead custom-fitted,and each deck board is a different size,so each can only fit properly in one po-sition. But with so many of them, itcould get a little confusing knowing

which one goes where. To simplify thematter, there are two lines drawn in anarrow like pattern on the tops of each setof deck boards. When fitted together cor-rectly, these lines line up very clearly,and serve much like the picture in a jig-saw puzzle.

Parts of the Tosa Wasen

Kawara カワラ Hull Bottom BoardKajiki カジキ Lower PlanksTana タナ Upper PlanksMiyoshi ミヨシ StemTodate トダテ TransomShino シノ Bow BeamOotoko おおとこ Stern BeamSekidai せきだい RailKoberi こべり Rub Rail (located

beneath the sekidai)Marukan 丸カン RingboltsRo 櫓 Sculling OarIsu イス ChairTekaki テカキ Hand PaddleHishaku 柄杓 BailerSugi すぎ Japanese CedarHinoki ひのき Japanese Cypress

Note that most of these terms applyspecifically to the boats of the Tosa re-gion. While there is much overlap withterms used elsewhere in Japan there arealso many, many regional variations.

Final Impressions

Building the Tosa wasen was likeone big lesson in traditional Japaneseboat construction. Going back to mycopy of Douglas Brooks’s book, I couldsee much of what he was describing inmy model. Of course, there are many as-pects of actual boatbuilding that are notexperienced in this kit but it definitely

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Figure 11, 12, & 13. The large scale of the model is actually a common scale used by Japanese boat builders and their models.This is the same scale that is commonly used in their simple “plank drawings” which record the key measurements for the con-struction of their boats.

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gives one a better sense of how theseboats go together. Anyone consideringscratch building a wasen model will gainmuch from building this kit first.

Purchasing the Kit

The kit is mostly easily purchaseddirect from the manufacturer. The com-pany’s website is http://www.thermal-kobo.jp, and since I began working onthe kit and blogging about it, it now ap-pears on the site. The simplest way tobuy the kit is to send an email toshop@thermal-kobo.jp to get final pric-ing. Payment must be made in yen usingPayPal. I ordered a second kit direct fromthe manufacturer and the total pricewith shipping (EMS) was only 15,400yen or about $130 at the time of thiswriting, and the kit arrived in about oneweek.

More Information

Douglas Brooks

For more details on Japanese tra-ditional boats, I recommend buying acopy of Douglas Brooks’s book, JapaneseTraditional Boatbuilding, which providesa great deal of background on these ves-sels and their construction, and detailsthe author ’s five apprenticeships withJapanese master boat builders. It is a fas-cinating read and very informative.While it is available from the major booksellers, if one purchases it from the au-thor ’s site one can get a signed and in-scribed copy, not available elsewhere,and the profits go to funding more of theauthor ’s research. Find out more aboutthis book and about Mr. Brooks’ work at:http://www.douglasbrooksboatbuilding.com.

Masaki Tanimura and Thermal Studio

Mr. Tanimura, the owner of Ther-mal Studio, which manufactures theTosa wasen kit, has a blog site that in-cludes a visual guide for building the kit.The blog is in Japanese, but the manyphotographs make the constructionsteps easy to follow. It can be found at:http://reishiki.exblog.jp/i8/. ThermalStudio’s website is at: http://thermal-kobo.jp.

Toshihiko Shibafuji and the Tosa Traditional Boat Society

Mr. Shibafuji manages the TosaTraditional Boat Society’s Facebook pageat: https://www.facebook.com/tosawasenHe studied boatbuilding with Japaneseboatwright Masaru Hiromitsu in theTosa region and has built his own tradi-tional Japanese boat. You can see photo-graphs on the Facebook page. He alsomaintains his own blog at:http://wave.ap.teacup.com/wasennfu-nadaiku/

My Tosa Wasen Build Logs

For those ship modelers thatwould like to follow my own Tosa wasenbuild, you can find my build log on TheNRG’s Model Ship World at :http://mod-elshipworld.com/index.php/topic/12152-tosa-wasen-traditional-japanese-fishing-boat-by-catopower-thermal-studio -small-110-scale/#entry367959

I also have another version of the buildlog on my own blog site at: https://ship-modeler.wordpress.com/category/ship-model-blogs/tosa-traditional-japanese-boat/