At Nara we visited the Yakushi-ji Temple (national treasure)  guided by Prof. Shigeatsu Shimizu and had a peek at the restoration site of the east pagoda from 730 A.D. (its twin is visible on the left side of the image). 

Afterwards we visited a carpentry specialized in sliding doors.

Mechanism with a hidden spring which holds the vertically sliding element in its place.

Wooden joints 1

Wooden joints 2

Trying tools ourselves.

Tools

Later in the day we were meeting up with a colleague from Kyoto Institute of Technology.