Helical Antenna Help!!!

Im trying to build a helical antenna that works for 2.4GHz... I wanna know what's the best possible material for the reflector and the center support. Its provided tat i can buy materials tat r more expensive than pvc tube and bla bla? One qns, we cant use metal in the center support?

There are many articles on the Internet. Using www.google.com and searching for 'helical antenna 2.4 GHz' gives many hits:

http://helix.remco.tk/
http://brneurosci.org/helix-antenna.html
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