Now for larger ham radio antennas I would probably go with aluminum tubing. Be aware that as you go larger the more aluminum tubing you will need and the more costly the antenna will become. Moxon Ham Antennas can be made out of a variety of products. For example the spreaders can be made from crappie fishing antennas and maybe some aluminum square tubing. The connectors can be the square block saddle clamps that can be purchased from dx engineering. Another important fact to remember is the higher the frequency, the bigger the antenna will be. So plan your homebrew ham antennas wisely, poor choices spell disaster.
Two other items to consider are what are you mounting this beast on and what will you turn it with. Small arrays for 6 meter and two meter can be easily turned with a small rotor. If you are building something say in the 20, 40 or 80 meter band, you will need a heavy duty ham antenna rotor. My advise is search on the internet and through youtube. This way you can get all kinds of ideas to implement into your ham antenna homebrew project for this spring.