If a make a dish antenna of steel and of fiberglass, which would be more heavy and also which would be more expensive?
a steel dish would be heavier but cheaper. fiberglass is lighter, however more time consuming to manufacture and expensive
Why not go one better. An aluminum mesh would be lighter than both for the same size and would not need to be painted. It would probably be more expensive than the steel however.
Steel will be heavier but easier to manufacture. There won't be a huge weight advantage because you can use steel mesh which works the same as solid, near enough, as an electromagnetic reflector. Steel can just be pressed, fiberglass has to be laid up of resin and mat and then allowed to cure. Fiberglass will also need to be coated in something conductive whereas you can just spray paint the steel, or even buy it pre-coated.
