Antennas may be fabricated from a variety of materials such as solid aluminium, sheet steel, fibreglass (with an embedded metal mesh or fine microwave reflective material included in the fibreglass resin) or steel mesh. The important characteristics are how well they reflect microwave frequencies and how well the dish maintains the desired parabolic shape. From this viewpoint solid aluminium or steel is probably better than fibreglass or mesh.
Other minor consideration during fabrication are coating the dish with non-reflective paint to reduce the amount of heat being focussed on the LNC and including a water drain hole to prevent water collecting in the dish.
It is possible to produce dishes up to about 1.5m in diameter as a single item by a simple pressing operation. Above this diameter a more complex metal forming operation called spinning is used to produce single piece dishes of up to perhaps 3 m diameter. For dishes of 2.4 m or larger construction in segments (petals) is often used because it simplifies manufacturing and subsequent transportation.
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