Hamshop.cz

Basic KIT for  3 el. yagi.
Contains:
1x element holder
1x dipole holder
1x coax holder
1x reflector holder
1x coax cover
4x plastic nut


You can buy more element holders and make more element yagi.
Parts are made from plastic and they are not designed for permanent outdoor use.

Boom diameter 25 mm - you can use PVC or AL pipe 
Elements - 3.2 mm Al welding rod
Dipole - 4 mm bras welding rod

You can make any type of antenna from:  http://www.qsl.net/dk7zb/PVC-Yagis/PVC-details.htm

More info:
http://www.thingiverse.com/thing:912567