[Jared Kotoff] asked an interesting question on Facebook. He asked if we had ever seen 3d printing in ice before. Though we couldn’t find anything in our archives, he managed to find a project that makes 3d printed ice sculptures. To do this, they actually print two materials inside a chamber that is -8 degrees Fahrenheit. The first material is Shortening Methyl Esther (SME) that is used as a scaffold or mold. The second material is just water, but the tip is heated to 68 degrees to keep it from freezing in the nozzle. They do two passes of water for every layer of SME, and scan with a laser and perform corrections after every five layers.
Once the print is completed, the sculpture has to be scraped clean of SME and then soaked in kerosine to remove the last of it. There are several pictures at the linked article, but sadly no video.