Design and Implementation of a Composite Printing Machine

The article focuses on the design and construction of a 3D printer capable of printing both traditional cement and alkali-activated cement (AAC). Research into alkali-activated cements, commonly known as geopolymers, has progressed beyond the basic research stage, with the current challenge being the implementation of practical applications. These include solving the shaping issues of AAC paste and forming the final shape of a given product. One of the most advanced methods for achieving this is through 3D printing. The printer was created by modifying the open-source RatRig V-Core 3D printer ecosystem design to fit this purpose. Based on these modifications, an appropriate material composition was determined, and printing tests were conducted, allowing development conclusions to be drawn. A three-dimensional model of the structure was first created using Autodesk Inventor 2024 CAD software, and critical load-bearing components were validated through simulation. Special attention was given to cost-effective manufacturability, with custom parts produced using 3D printing, while additional components (e.g., bearings, fasteners) were selected from commercial catalogs. Finally, test prints using the specified material composition were performed to examine potential construction improvements for the 3D printer and assess material properties. The core concept of the cement printer lies in the material deposition method, specifically, in achieving effective extrusion of the paste. Five different versions of this were tested, which will be discussed in detail.