From digital crafting to digital manufacturing: automated production using hybrid 3D concrete printing

3D Concrete Printing (3DCP) has undergone a significant growth over the last 20 years and more recently, methods for improving surface finish and manufacturing accuracy have been explored by applying secondary shaping processed, post printing. These approaches are termed ‘hybrid’ manufacturing and a promising method is to use milling when the concrete is in its green state. The achievable precision and resolution of detailing is an order of magnitude greater than 3DCP alone and greater complexity than can be readily achieved in casting is possible. This step change in manufacturing capability enables a complete rethinking of design, but to date there has been no work published. This article presents the hybrid process and explores the potential for design and manufacture based around ‘The Canopy’: a full-scale demonstrator project. The article reports on the narratives around establishing the design constraints and how they influenced the achievable detail, leading to the identification of 26 features that were used to classify the material and process constraints that need to be interpreted to achieve a manufacturable assembly. An identified challenge of implementing this and other cement-based digital fabrication methods, is the tacit knowledge required by operatives to create successful outcomes. By taking the output of this work and embedding constraints in design software, this could be avoided moving such processes away from digital crafting and towards digital manufacturing.