How is the honeycomb structure formed?
The honeycomb sandwich structure is formed by melting the glass into a mold which is the negative of the desired honeycomb shape. The glass fills the voids in this mold and becomes a honeycomb structure. The main components of the mold are a cylindrical tub which sets the outside shape and alumina-silica hexagonal columns or cores which form the voids in the honeycomb. Each of the hollow core boxes is held down against the floatation force with a special silicon carbide bolt. The cylindrical tub is held together by bands of Inconel 601 which wrap around the outside of the mold in a manner similar to hoops of steel around the staves of a barrel. After the honeycomb structure has been cast and cooled, the mold material is removed by breaking it apart with a high pressure water spray. • Why are the mirrors figured as paraboloids? Mirrors for large reflecting telescopes are polished to precise paraboloidal (figure of revolution like a parabola) or nearly paraboloidal shapes. This shape can
