A wonderful video from Doctoral Student Meghan Trainor and Professor Mark Ganter of the University of Washington shows the entire process of producing 3D printed ceramics. The initial fragile print made from a glass powder formula is placed into a furnace for firing and solidification. 
An ongoing issue with the process, which is still under development, is the shrinkage that occurs during firing. The team is experimenting with a variety of mixtures to understand how best to tackle the problem. Via Technovelgy and YouTube
