Need help building 1st homemade!!!

[Gilgamesh]

Hello,
it could be that my english isn't very good, apologize for that.

I need some help with making my first homemade, I have a concept but I do not know way is to build and from wich material.
So can anyone help me with this plzzz?? After a few weeks, I have three months vacation and then my idea was to start building my homemade idea, but I'm not ready yet to start building... Plzz give me some help? I live in the Netherlands and we do not have such great stores where you most people can buy your PVC stuff...so I must know exactly wich parts I must buy and wich not.
Or give suggestions for material or building or what you think I must know. Everything is welcome.
The first picture is with description of the parts and the second and third one is my first concept and what I thought I need:

homemade-design.JPG (47.46 KiB) Viewed 2443 times

What I forgot to say was, I want that fanta bottle screweble on and of my homemade, wich fitting do I need for that?
It could be this isn't the right place to post it, but I didn't know any better place so...excuse me if I'm not right. lol nice smiley's.

[isoaker]

While definitely a concept, you'll more likely get better advice and suggestions on your design at the Super Soaker Central forums. I'd post this info there as well if you haven't already.

[martianshark]

I was going to post what iSoaker said.

The design looks pretty cool.

[Gilgamesh]

Ok ty man, I will do that.
I spend a lot off time to fully make it.