TECHNOLOGY The evolution of contemporary massive timber con struction (often shortened to ‘mass timber’) is inextricably linked with the application of digital fabrication technology to components of architectural scale. This in turn has been made possible by the development of design software capable of modelling entire structures in three dimensions, and generating fully dimensioned fabrication drawings complete with tolerances, for each structural member and all other elements. These digital files can then be used to program computerized numerical controlled (CNC) machines that can cut, plane, drill and rout components of almost any size and shape. The accuracy of CNC machining also makes the integration of a new generation of high-strength proprietary connection systems possible.
58 | PRINCIPLES OF TALL WOOD BUILDINGS
CNC MANUFACTURING
While CNC fabrication lends itself to the creation of complex shapes, the principles behind the technology are quite straightforward. The term CNC simply refers to a manufacturing process in which the machining tool is instructed and controlled by a computer program. The process can be applied to any material, and was first used in the 1940s, to machine the increasingly complex aluminum parts required by the US aircraft industry. The application of CNC technology to the manufacture of wood furniture dates to the 1970s, with the introduction of machines that could move with precision along a single axis to drill simple holes. Next came two-axis machines that could make a saw cut perpendicular to the initial path of travel, then three-axis