Magnetic Joint upgrade for Rostock

Material used:
12x 10mm M3 screws
12x M3 nuts
12x 12.7mm steel balls
http://www.supermagnete.de/K-13-N
12x 6x6mm Neodym magnets (joints)
6x 6x6mm Neodym magnets (effector)
http://www.supermagnete.de/S-06-06-N
(http://www.supermagnete.de/S-06-08-N may be used for joints too)
2x 1000x6x1mm aluminium pipe (EAN 4004338473419)
http://www.amazon.de/Rundrohr-silb-elox-6x1-Aluminium-1m-7341/dp/B0029ZZ7BG/
Use 6x2mm Neodym magnets for snap-on accessories (like radial fan)
http://www.supermagnete.de/S-06-02-N
effector_offset is 33mm
carriage_offset is 22mm
joints should print fine with 0.5mm extrusion width, walls should be perimeters only