The invention is generally a 3D printer configured for printing 3D objects using a high-viscosity photosensitive material. The 3D printer may include a fluid retaining assembly which comprises a rotating tank. A printing platform is situated in a manner such that a bottom surface of the printing platform makes contact with the printing solution in the tank. To facilitate printing using the high-viscosity printing material, a scraper assembly may be implemented in order to properly prepare the printing solution onto a surface of the tank. The scraper assembly prepares the material by scraping a layer of the material onto the surface of the tank for facilitating curing of the layer onto the printing platform.