立川富房著『軒廻棰雛形』の扇垂木について: 要(かなめ)のない扇垂木の技法

摘要

In fan raftering, rafters are usually arranged in a radial fashion from the Kaname (center point). However, there is a fan raftering technique that does not use Kaname. This technique is described in a wood-block printing book titled Nokimawari Taruki Hinagata, as follows: 1. The space between each rafter is determined according to the drawing, using Matsuba-gane 2. Radial arrangement of rafters is determined by dividing the length difference between the hip rafter and the eave in the central part of the roof in proportion to the number of rafters.%扇垂木の技法は一般に鎌倉割と等間割の二つの技法があるとされる。それぞれ方法は異なるが軒先廻りで垂木先の位置を割付けた後、垂木尻を要(かなめ)に結ぶことによって垂木を扇状に配置するもので、通常要は扇垂木を作図するための必須の基準である。