Post 77 in an ongoing series describing the design and construction of a kabukimon, a type of Japanese gate. This is a project for the Museum of Fine Arts in Boston. Post 1 in this series can be found here if you'd like to start at the beginning. Each post links to the next at the bottom of the page. Recent installments also to be found in the 'Blog archive' index to the right of the page.
I started off by patching a knot hole on the back of the kabuki. Then I filled various cracks here and there on the kabuki and main posts with some structural adhesive. Not really worth taking pics of that.
Then the main task of the day, which involved dimensioning, shaping and cutting the joinery on the nuki, or penetrating ties:
The nuki attach to the main posts with a wedged half dovetail, kata-ari-otoshi, and to the rear support posts by a wedged cogged joint, watari ago.
While it may not be obvious from the above sketch, the rear posts are wider apart than the front posts, so the lower nuki splay outwards on the horizontal axis, and have simple angled cuts for the abutments and end cuts. The upper nuki, however, splay outwards and slope downwards, creating compound joinery at the intersections with other members, one of my favorite things.
To avoid creating parallelogram-shaped mortises, the upper nuki are 'backed' so that they are no longer squared sections:
A little closer look:
So, though the gate structure looks elementally simple in many respects, we have the situation of non-square penetrating ties passing through non-square rear posts, and virtually nobody looking at it is going to notice any of that. That aspect - apparent simplicity as a product of underlying complexity- is one of the things I like the most about the Japanese carpentry tradition.
The stock had been roughly dimensioned a couple of months ago or more, and being quartersawn premium material have remained very straight in the interim. I took them down to size, processed the uppers into parallelogram-sections, and then super surfaced everything. Then it was joinery layout and cut out. There went most of the day. The afternoon rolled along without a hitch, and I could fit the stretchers one by one to the main posts. Here's a short video showing the fitting of one lower nuki:
A while later, all four were in place on the main posts:
The cogged joints on the under-surfaces of the nuki are visible in this view, if you look towards the top of the pic.
Why not a view from the other direction as well?:
Tomorrow morning I'll fit the nuki to the rear posts, then on to further thrills and spills. The nuki were the last substantial bit of joinery fabrication on this project. Now I have lots of wedges, splines, and so forth to make, along with some sub-assembly work and, oh yeah, a whole lotta finish planing.
Thanks for visiting the Carpentry Way. On to post 78