Guest: Behrokh Khoshnevis. Topics: 3D Printing and Contour Craft for Earth & space applications. Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, http://thespaceshow.wordpress.com. Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information. In addition, please remember that your Amazon purchases can help support The Space Show/OGLF. See www.onegiantleapfoundation.org/amazon.htm. For those listening to archives using live365.com and rating the programs, please email me as to why you assign a specific rating to the show. This will help me bring better programming to the audience. We welcomed Dr. Behrokh Khoshnevis to the program to discuss 3D Printing and Contour Crafting which Dr. Khoshnevis invented. For more information, visit www.contourcrafting.org, www.craft-usc.com, and www.bkhoshnevis.com. In our first segment of our 1 hour 45 minute discussion, Professor Khoshnevis provided us with an overview of 3D printing, its history, strengths and weaknesses. He also took us through the three main methods of fabrication and their subsets. We talked about state of the art manufacturing processes and several times during our discussion he said 3D printing would never replace modern manufacturing which would always develop along the cutting edge in advance of 3D printing techniques, processes, and speed. He talked about the materials being used for the printing and the strengths and weaknesses of them. We began talking about 3D printing in aerospace and he talked specifically about "layering." During this segment, he told us how he started looking for new processes for printing large structures which is what contour crafting is so good at doing. He explained contour crafting in construction and he identified multiple specific uses for it. Since he had already talked about how slow the process was with 3D printing, he made a point of saying that contour crafting could be hundreds of time faster than just regular 3D printing. In talking about aerospace, he explained why logistics can be a problem. Later in the segment, we talked about the significant power needs even in space, plus the high use of water. Because of the water, he told us about substitute methods that made it possible to not use water. He said meaningful structures could be made such as habs. He fielded several listener questions, including some that asked about 3D printing being a magic solution, especially for space applications. In the second segment, our guest was asked about the impact of microgravity and radiation on contour crafting and 3D printing. Doug called in and talked about inflatable structures rather than construction of structures. Our guest offered Doug important observations about the inflatable structures. We also asked about the high demand for water by these printing processes. Behrokh said that water usage might be a problem but by using sulfur and insitu resources, there would be alternatives to water. A listener asked him if a spacesuit could be printed. Our guest said not likely giving the reasons for that thinking. We talked about 3D printing of food, medical supplies & medicines. As we were ending, I asked the professor for the level of interest his students show in the contour crafting and 3D printing fields. His response might surprise you. Post your comments/questions on The Space Show blog above. You can email our guest through his websites or me.