Over the past few years, additive manufacturing (AM) has successfully implemented the motto "making the impossible possible" in a wide range of applications. The possibility of easily having a 3D printer at home is fascinating for many. Although AM seems to have fully arrived in industry, it is not yet established in many areas and there is still a high need for research and development. A special requirement in materials research is to perform AM processes with materials that were considered impossible to utilize in the past. One of these classes of materials is glass. Various approaches to additively manufacture glass are being pursued worldwide. These can be divided into processes with and without binders. In order to manufacture transparent optical components without defects, interfaces and inclusions, a binder-free process is required. ~