Conversion. Copper and brass processing. Here is a stock of billets, or solid cylindrical brass or copper castings, which have been sawed to length. These billets will be heated and put through a powerful extrusion machine, which will extrude rods, tubes or other special shapes from them. Billets are cast six inches to eight inches in diameter and usually from four to ten feet long. These are sawed to shorter lengths before they go to the extrusion machines. Chase Brass and Copper Company, Euclid, Ohio