Straightening Buckled Castings

1909 Scientific American  
be heated over a stove. While the shade is still hot a piece of wax or ordinary candle is rubbed over both sides of the brass. The heat of the brass melts the wax and forms a thin wax coating. When the brf,;;a be comes cold, the design, which shows through the wax, is traced with a pointed in�trument. The parts of the brass which are to be burned out are. scraped free of wax. The shade is then immersed in nitric acid. The acid eats through the exposed brass and the required design is very
more » ... esign is very cleanly cut out. The lamp, electric, and drop-light shades are made in the same way. Without much expense or trouble these larger pieces can be improved by placing dif ferent colored glass behind the designs.
doi:10.1038/scientificamerican02061909-121f fatcat:kfghmqgarngqxf266m7rwc2dxu