Called 'Doing DaVinci'
http://dsc.discovery.com/tv/doing-davinci/doing-davinci... - they build some of DaVinci's inventions that had never been constructed, just known from his drawings. The episode I watched today was building his siege ladder - an amazing design that worked very well, though I spotted a weakness that the defenders of their "castle" did not attempt to take advantage of This was only the second episode - it seems to run at 10 PM ET on Mondays and rerun on Sundays at 1 PM ET.
A review:
http://www.associatedcontent.com/article/1678287/doing_...