Sourcing Timber for a Japanese Wooden Boat

By far the most difficult part of preparing to build two boats with Douglas Brooks has been sourcing timber that meets our needs in Australia. The short version is, we have not been able to. It would be financially ruinous, if not actually impossible, to build a series of traditional Japanese boats out of Australian timbers in the 21st century.

So, these boats will be built from timber that we are importing from Japan. As you can imagine, we have had to bring in quite a lot more timber than we will need for the boats in order to justify the shipping cost, and we will be selling this timber from February.

This has been a bit of an adventure for me, and so for your interest, and as a bit of a therapeutic exercise for my own stress around this project, I'd like to share with you the angles we have covered and the attempts we have made to build these boats from Australian timbers.

Every Japanese woodworker I have known has a thrifty eye for timber - for example, when organising kanna-making classes with Takami Kawai in 2019, I asked him if I would need to import white oak (shirogashi) from Japan, to which he responded incredulously, "Don't you have any timber in Australia?"

I found this instructive. Japanese plane blocks are made from white or red oak because those timbers are durable, stable and available. There may well be even more well suited timbers out there, but if you can't get them easily or affordably, they are not the solution to the problem.

How do we adopt this approach for the upcoming boat building classes? Well, we identify the properties our timber needs to have and source something locally to suit. So what are those properties?

First of all, this timber needs to be soft. The seams of these boat will be fit together with hand saws and then edge-nailed, with those seams becoming water-tight and almost invisible. Fitting those seams with a handsaw requires soft timber that can be shaved away with repeated passes, and the saw needs to leave striations behind it in the kerf.

This softness is also allows the timber to be bent into position using levers and props. The sides will be pinned to the ground next to the bottom while they are worked, and nailed in that position to keep them there. So a level of flexibility is essential.

Secondly, the timber that we use will need to be large in section - 300mm or wider. It also needs to be at least an inch thick, and the lengths need to be somewhere about 5 metres long.

In Japan, the timber used in these boats is almost always sugi (Japanese cedar). To assess other timbers' suitability for boatbuilding, Douglas uses their Janka hardness. This is a test that measures the force required to push a steel ball bearing into the timber.

The Janka hardness of Sugi is 1420N (Newtons). When teaching in America, Douglas happily uses Eastern White Pine (pinus strobus) to build boats in those classes. It's Janka hardness is 1690N. It works really well, and Douglas can get a sawmill to saw him up slabs as large and as long as he desires at very reasonable cost.

So what timbers do we have in Australia that could work? I can tell you now that Western Red Cedar is perfect Janka-wise (1560N) - but have you tried to find it in 300x30 sections? One bloke laughed at me. Another quoted me $1200 a stick for stock half that width. So scratch Western red.

I love the idea of building a Japanese boat in Tasmania out of Tasmanian timber. Imagine the smell. Imagine the lustre. Imagine... Well, imagine the cost of a kidney. Then double it.

We have done some atrocious things to the natural environment in this country, including the indiscriminate logging of Tasmania's native rainforest species, many of which have glacial growth rates (I'm thinking of Huon pine especially here).

The net result of this is that Tasmanian timber cannot be treated as a renewable resource. It is non-renewable. There is what there is, and there won't be much more for a very, very long time.

Huon and Celery Top can be discounted anyway thanks to their Janka hardness being over 4000N. King Billy Pine, on the other hand, well, it would be absolutely perfect, with a Janka hardness of about 1200N (unconfirmed). It is renowned for it's workability and it's straight grain. And for being as rare as hen's teeth.

I did actually find a contact down in Tassie who knew of a pallet of King Billie Pine, squirelled away somewhere. They were kind enough to tell me that it would cost something like $30,000 per cubic metre, and that they wouldn't sell it to me anyway. Well. Tassie timber was not going to be an option.

Let's tackle the problem from the other end - what species are available in relatively large sections at a realistic price? We have some experience there. We could try radiata pine (perish the thought). We have used hoop pine in our kumiko classes with Wiggy. We brought in a cubic metre of large monterey cypress sections for our teahouse build with Greg and Ryo. And we actually have some very big bits of norfolk island pine in the workshop at the moment.

All of these species have a Janka of 2800 or higher. To check, we sent Douglas over a sample of Monterey Cypress (cupressus macrocarpa). This is an introduced species native to north America that was planted widely in Tasmania, Victoria and New South Wales as windbreaks on properties. Unfortunately, Douglas thought it would be very difficult to produce watertight seams with.

So I scratched any timber with this sort of Janka. Maybe they would work - but as we will be launching the first boat in front of hundreds of people at the Australian Wooden Boat Festival, it would be a very public lesson to learn if they actually don't.

There is only one species on my shortlist that comes in softer than Sugi in it's Janka number, and that is Paulownia (1330N). Paulownia is actually plantation grown in Australia (or at least it has been at some point), and is a staple for sufboard makers who do all sorts of beautiful things with it.

But I'll be buggered if I can get anyone who has some to call me back. The surfboard timber suppliers I could find didn't have enough of it. Wood retailers told me they haven't seen big sections of it for a long time. And any number or email address I could find associated with a paulownia plantation never got back to me. If you are in on the Paulownia game, let me know. I really want some.

At this point, I'd like to give an honourable mention to Silver Quandong (eleocarpus somethingorother), which has sounded promising but I have not been able to get a sample of or a Janka number for. Also for Sitka Spruce (picea sitchensis), with a Janka of 2270N but without a source I could find. And for Monkey Puzzle, an Asian species I read about with a good Janka but have also not been able to find.

And then there is Jelutong. The carvers who are reading this may be familiar with this South East Asian timber. It is very soft (1740N) but has very fine fibres, and so is quite popular with carvers for being easy to work while still holding detail. Furniture makers are usually overlook it for it's complete lack of any interesting grain.

I was able to find a source for Jelutong. Luke at All-Class timbers in Port Kembla had milled a tree. 300mm wide sections, an inch thick, in lengths from 2.8 to 5.8 metres long. Bingo. I bought everything longer than 4 meters. It was enough for one boat. I didn't care. I needed a win.

But I still needed more timber.

Where do you go from here? Well, we went to Japan. We bit the bullet and called upon some of our amazing friends and contacts, and we invested as much money as we could set aside on Japanese timber. It is almost entirely Sugi and Hinoki. We bought boatbuilding sections, we bought house construction sections, and we bought shiplapped cladding. And the container arrives to the Kogarah warehouse tomorrow, two weeks before Douglas lands in Hobart. And people wonder why I bite my fingernails.

So, the classes are on! The timber is here, the tools are in the process of being sharpened, and I simply cannot wait for the first morning of the first class when I can switch gears into woodworking mode and learn how it is that forty metres of timber can be turned into a boat in five days.

If you would like to join us, we still have a couple of spots available in both classes (Tasmania in early February and Sydney in early March). Or, if you'd just like to get your hot little hands on some Japanese timber, we will be back next week with some piccies and some prices.

All the best,

PS and, in case you are looking around for relatively soft timber, here are the species I considered and their relative hardnesses:

Common Name Botanical Name Janka lb/f Janka N Avg Dry Weight (kg/m3)
Sugi Cryptomeria japonica 320 1420 360
Monterey Cypress Cupressus macrocarpa 620 2750 515
Queensland Kauri Agathis robusta (and A. microstachya) 560 2510 470
Kauri Agathis australis 730 3230 540
Hoop Pine Araucaria cunninghamii 750 3320 500
Norfolk Island Pine Araucaria heterophylla 650 2890 495
Monkey Puzzle Araucaria araucana 400 1780 535
Paulownia Paulownia tomentosa 300 1330 280
Huon Pine Lagarostrobos franklinii 920 4110 560
King Billy Pine Athrotaxis selaginoides 1200? 500
White Cypress Pine Callitris glaucophylla 1360 6060 650
Celery Top Pine Phyllocladus aspleniifolius 4500 645
Jelutong Dyera costulata 390 1740 450
Basswood Tilia americana 410 1820 415
western red cedar Thuja plicata 350 1560 370
Australian Red Cedar Toona ciliata (syn. Cedrela toona) 700 3130 485
Northern white cedar Thuja occidentalis 320 1420 350
Southern Silky Oak Grevillea robusta 880 3930 590
Radiata Pine Pinus Radiata 710 3150 515
Eastern White Pine Pinus strobus 380 1690 400
Cedrela Odorata 600 2,670 470
Elaeocarpus Grandis 2800 453
Deodar Cedar 3700?
Sitka Spruce Picea sitchensis 510 2270 425
Camphor Laurel Cinnamomum camphora 950 4440 520
Tassie Myrtle Nothofagus cunninghamii 1310 5840 625
Caribbean Pine (Aus plantation) Pinus caribaea 1110 4920 625
Slash Pine (Aus Plantation) Pinus elliottii 760 3380 655