How is this Japanese joint constructed?

  • Advertise with us

« back to Joinery forum

Forum topic by BTimmons posted 02-26-2013 05:27 PM 7264 views 0 times favorited 15 replies Add to Favorites Watch
View BTimmons's profile


2301 posts in 2092 days

02-26-2013 05:27 PM

Topic tags/keywords: question joining joinery japan japanese

I’ve had this lamp sitting in my favorites for a long time. The half-laps forming the swirling pattern on the shoji style screens are one thing, but I’ve never been able to figure out how the corners of this piece (the meetings of the X,Y, and Z axis) are put together. I have some mental pictures of how I might do it, but none of them actually look right in my head.

The Japanese tradition has all kinds of brilliant and intricate joints, and I’m not sure what most of them are even called. So searching for this on Google has been problematic because I never know exactly what to look for.

So, does anyone have any references on this particular joint? Diagrams, videos, blog posts, anything?

-- Brian Timmons -

15 replies so far

View Jorge G.'s profile

Jorge G.

1537 posts in 2082 days

#1 posted 02-26-2013 05:33 PM

Here you go, in this case it is for one of the computer cases he built. But I imagine the joints are the same. Pretty impressive hand work.

-- To surrender a dream leaves life as it is — and not as it could be.

View CharlieM1958's profile


16261 posts in 3825 days

#2 posted 02-26-2013 05:41 PM

Brian, I don’t know about you, but, after looking at the information Jorge posted, I can tell you I’m not about to rush out to the shop and attempt those joints!

-- Charlie M. "Woodworking - patience = firewood"

View stnich's profile


117 posts in 2532 days

#3 posted 02-26-2013 05:45 PM

Here is the link to Nick’s computer case that shows how he created the joint. I thought that one of the tenons might not be a through tenon. I have had this on my favorites list for a long time myself. Beautiful work.

View BTimmons's profile


2301 posts in 2092 days

#4 posted 02-26-2013 05:48 PM

Ask a question and get the right answer five minutes later. Damn, I love this place! Thanks, fellas.

-- Brian Timmons -

View BTimmons's profile


2301 posts in 2092 days

#5 posted 02-26-2013 05:49 PM

And yes, while it looks really tricky, it’s nice to have a challenge.

-- Brian Timmons -

View Loren's profile


8588 posts in 3255 days

#6 posted 02-26-2013 05:52 PM

I am not sure it is anything but a decorative joint with false
parts. Japanese joinery is derived from timber framing
and in timber framing such a 3 way joint would be weak.
Aesthetically it is cool though.

There is a sort of real joinery variant where one tenon
is full width and goes through the mortised timber,
with a wedge or not on the other side. The other
tenon is half-width and goes through the mortised
timber, and the other tenon, and is wedged.

View CharlieM1958's profile


16261 posts in 3825 days

#7 posted 02-26-2013 06:07 PM

Loren, if you follow the links posted, you’ll see it is pretty much the latter you describe.

-- Charlie M. "Woodworking - patience = firewood"

View waho6o9's profile


7639 posts in 2184 days

#8 posted 02-26-2013 06:07 PM

Japanese joinery is amazing.


View Don W's profile

Don W

18252 posts in 2175 days

#9 posted 02-26-2013 08:20 PM

i’ll just watch.

-- - Collecting is an investment in the past, and the future.

View RussellAP's profile


3080 posts in 1894 days

#10 posted 02-26-2013 08:26 PM

It looks like the corner, where everything comes together is about 2×2. I don’t know how they did it but I’d just give each piece coming into the corner a 1/4 of the area and slip them all together with some glue and a tight band. Now how the heck you do that with all 8 corners at once is a mystery to me.

-- A positive attitude will take you much further than positive thinking ever will.

View Ripthorn's profile


1433 posts in 2592 days

#11 posted 02-26-2013 08:36 PM

It’s frequently called a puzzle joint. I watched an episode of American Woodshop or some such thing with Scott Phillips where he did a similar joint on the base of a walnut coffee table. Didn’t look impossibly hard, but not something I care to make personally.

-- Brian T. - Exact science is not an exact science

View BTimmons's profile


2301 posts in 2092 days

#12 posted 02-27-2013 05:30 PM

I think I finally found a solution. This page includes instructions and illustration on assembly.

I just think it’s a neat puzzle joint. And like Loren pointed out, it wouldn’t be all that useful for timber framing, but it’s a fun mental exercise nonetheless. And used in something like a lamp that won’t have to support a heavy load, it’s a nifty touch.

-- Brian Timmons -

View RichCMD's profile


363 posts in 1548 days

#13 posted 02-27-2013 07:29 PM

Since the final step of assembly involves twisting the C piece, it seems like you would need to give a lot of thought to the assembly order and determine which are the A, B and C pieces in each of the 12 joints. I think it may really be a puzzle.

-- Ride the bevel!

View BTimmons's profile


2301 posts in 2092 days

#14 posted 02-27-2013 07:50 PM

Rich, I was thinking that too. Makes me wonder if, instead of using the rounded connector, maybe stub tenons that meet in the middle of the intersection?

It wouldn’t be a true puzzle joint if that were the case, but if one wanted the overall structure to actually remain in place, and I assume glued, that seems to be the only way to do it.

-- Brian Timmons -

View JADobson's profile (online now)


797 posts in 1718 days

#15 posted 12-29-2014 12:57 AM

Sorry to resurrect such an old post but I’m wondering if you ever made the lamp Brian? I’d like to try one myself and am wondering if you had any tips.

-- No craft is very far from the line beyond which is magic. -- Lord Dunsany

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics