Thread: A Japanese timber framed garden shed

Ah well, that was at the end of my international career and I have to say, the peak of it. We only rarely had time to venture out of Narita village, but there were plenty of back streets to explore. Even modest homes had beautiful cedar features. There is a temple there that was established 1160 years ago and they are still perfecting the ~40 acres of gardens. Massive timber construction. Even the most modest outbuilding is done with the expected attention to detail. Not exactly harmonious designs, but I guess because they are largely ceremonial.

You can wander the back streets and find vending machines on the sidewalks, unmolested. Cold beer, hot canned coffee. What a world. .

Japan is one of the few places that I would actually pay retail to revisit. And I hate paying retail.

Lovely. Thanks, Greg.

Some joinery at last. This is the wedged half dovetail I'm using to connect the horizontal tie boards (nuki, 貫) to the posts. Functionally like "girts" in Western timber framing. Old school Japanese framing didn't use much diagonal/knee bracing so instead they used multiple nuki to resist racking/shear forces. From what I can tell they used either this or pegged mortice and tenons. I like the half dovetail because in tension it get stronger as the dovetail is compressed.

In the pic the post is horizontal and a short scrap nuki to test the fit is vertical. For scale the mortice is 145 mm x 30 mm and 90 mm deep. If you stare at it you might recognize that the joint is housed so the nuki bears on its full width/depth.


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To make the mortice I started with a router template clamped to the post centerline. Then routed 15 mm deep. That got me the depth of the housing and established a consistent reference surface for excavating the rest of the mortice.


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Then a I used a 28 mm auger to drill out much of the waste for the 30 mm mortice. I hoped that difference would give me enough clearance to accommodate sloppy free hand drilling yet not require too much chisel cleanup after. I think I got it right at least on the first attempt. The other block is there to let me know when I hit the 90 mm depth. I really, really did not want the lead screw of the auger to blow through the show face opposite the bottom of the mortice. I gave myself 30 mm of buffer but still. One mistake would be a very bad day. Work to do first thing in the morning, not at the end of the day.

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I'm enjoying this greatly.

I also follow a few Japanese Instagrammers who are building-erectors....

ryo5610（株）藤本工務店
Kokichi @ Chantarokichi

There are many. The first link shows how vigorous the building process can be!

I have only ever used western chisels to chop mortices. Can you please post a picture of what you used?

I like that joint very much and get that it is self-wedging. Obviously seismic disturbances wouldn’t bother it.

Originally Posted by Greg Q

I like that joint very much and get that it is self-wedging.

There have been a few politicians that were good at that too.

I'm not going to even offer a response, but I am giggling.

This book may be illuminating...

The Building of Horyu-Ji: The Technique and Wood that Made it Possible - T & Kohara; J Nishioka

It comes up for sale periodically


This is a description... The Building of Horyu-Ji by T & Kohara, J Nishioka

Originally Posted by Greg Q

I have only ever used western chisels to chop mortices. Can you please post a picture of what you used?

I'm using the chisel on the top, a 30 mm atsunomi. It is a serious piece of steel. For size comparison just below is a standard Japanese bench chisel. Below that is Japanese mortice chisel. Those mortice chisels are much like the Western versions except they are usually shaped with square parallel sides rather than slightly tapered sides. The largest mortice chisels are usually 12 or 15 mm and are used mostly for furniture and door making. Any wider than that and they tend to get stuck in the mortise.
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For paring the mortice side walls I have these two slicks, ootsukinomi.
The Varieties of Japanese Chisels Part 15 – Ootsuki Nomi 大突き鑿 – Covington & Sons Tools. One is 24 mm and the other is 48.

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Thanks Gary. Those are beautiful tools. I have a set of carpentry chisels I purchased from Mrs Ishiwata's hardware store in Narita but was planning to find some finer ones on my next trip which didn’t happen. Those slicks are admirable, but I look at them and then think of dropping one on my foot.

Thanks for the link. I am going to enjoy reading that whole series.

Greg

Originally Posted by woodPixel

This book may be illuminating...

The Building of Horyu-Ji: The Technique and Wood that Made it Possible - T & Kohara; J Nishioka

Ah, thanks. I've put it in my "to get" queue.

Two other sources for traditional Japanese construction I've found that others might find interesting:

1) Anything on the late Chris Hall's blog, The Carpentry Way. Go through his build index and topic index or just start at the calendar beginning around 2009. In my opinion, Hall was a genius. Both a skilled craftsman and scholarly student of Japanese carpentry. His monographs are superb and far better, and less expensive, than any commercial books available. The pdfs are still available and proceeds go to his young family.

The Carpentry Way – Designing and building in solid wood, emphasizing joinery with minimal use of glue or metal fasteners.

Kezouro-kai USA. Homepage - Kezurou-kai USA

Originally a Japanese planing competition to see who can achieve the thinnest shavings. Their USA branch has expanded to support and train other aspects of Japanese woodworking such as Japanese carpentry and joinery. They offer online Zoom classes. Joining for little money gets you a discount on their classes.

Incremental progress. Mortices chopped on two posts. One post shown here. Each post takes me two days, working maybe 4-5 hours per day. Four more posts to go then on to the horizontal beams. My plan is to do all the mortices first and then go back and cut all the tenons to fit.

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The bottom ones look a bit scary. I enjoy cutting mortises though. It's going to be really interesting watching them come together.

Gary, even your saw horses are works of art. Which just made me realise what all my cedar offcuts are going to become. Keep 'em coming..l

Originally Posted by BEM

The bottom ones look a bit scary. I enjoy cutting mortises though. It's going to be really interesting watching them come together.

Ha! Wait until you see the tenons!

I'm using a slight variation on the three-way beam-to-post joint I tried in my joinery model. I changed the look of the upper stub tenons to make it a little easier to cut out with a single template. There are two of the joints in the shed.

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Here's more or less what it will look like assembled, (without the post in the way).

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And assembled:

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And from underneath:

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Truth be told, being able to try joinery like this full scale was the main reason for me doing the shed. I love the challenge of 3D thinking needed, the clever interlocking, getting the layout and cutting right, and, maybe perversely, that almost all of it is hidden in the finished structure. I've done similar successfully on furniture which gave me the idea I could do it at this scale. How cool to build a piece rather like furniture but to be able to step inside it! But now that I've started I see this is a whole new game. Humbling.