After a couple of years that I follow 3D printer growth, I picked up all the best solutions, as magnetic joints and prismatic linear guides, and gather together in this project.
A complete 3D Delta Printer that can be built with about 200 euro (with electronics and graphical display, hotend and motors excluded).
Printable area: 200mm dia and 200mm height
Q*Bot is based on commercial Aluminum "L" profile, 25x25x4, which work as structure and linear guides as well. It's steady, fast...