American cinematographer (Feb-Dec 1929)

September, 1929 American C i n e m a t o g r a p h e r Thirty-seven HeatTreatment of Steel "The Heat Treatment of Steel" is the subject of the latest addition to the library of educational motion picture films produced by the Department of Commerce for the visualization of the mineral industries of the country. The film was made, under the supervision of the United States Bureau of Mines, in co-operation with one of the large automobile manufacturing companies. It is brought out that some 1475 separate steel parts of a typical automobile must be given special heat treatment, illustrating forcibly the importance of this process in the automotive manufacturing industry. The film begins with a few scenes illustrating the early days of motoring and recalls to mind the fact that the automobiles of the nineties were extremely uncertain quantities as compared with the dependable and efficient motor cars of today, which the heat-treatment process has helped to make possible. The old-time methods of tempering steel, with anvil and forge, when the color of the metal alone indicated the degree of tempering, are shown. Then in contrast, the various steps in the modern methods of heat treatment, utilizing specially designed furnaces subject to the utmost precision of control, are illustrated. The heat treatment of steel, it is pointed out, is the process of so heating and cooling the metal as to intensify the hardness, toughness or flexibility of the steel. It is shown how the furnaces are heated by crude oil under pressure, constituting a baking process with the source of the heat away from the metal. The use of extremely delicate electrical temperature indicators, or pyrometers, for the automatic regulation of the high temperatures is visualized. Other scenes show the cooling of the heat treated parts in an oil bath, composed of 4,000 gallons of special, expensive oil kept in constant circulation. The various steps in the forging of the front axle of an automobile are depicted, from the time that the chemist analyzes the steel for the carbon content which determines the extent of heat treatment required. Microscopic comparisons of the steel before and after its subjection to the heat treatment process are shown. The process of surface hardening of the steel parts is also depicted. Various processes of physically testing the heat-treated steel are illustrated. Copies of this film, "The Heat Treatment of Steel," are now available for exhibition by educational institutions, churches, clubs, civic, business and military organizations, and others who may be interested. Applications for the use of the film should be addressed to the Pittsburgh Experiment Station of the United States Bureau of Mines, Pittsburgh, Pa. No charge is made for the use of the film, although the exhibitor is expected to pay the cost of transportation both ways. To be Abreast of the Times Subscribe to THE AMERICAN CINEMATOGRAPHER Roy Davidge Film Laboratories Negative Developing and Daily Print exclusively 6701 SANTA MONICA BLVD. HOLLY 1944 ^Amateurs! If You Take Your Pictures Seriously, You Cannot Afford to be Without the (Cinematographic Jlnnual now being prepared by the AMERICAN SOCIETY OF CINEMATOGRAPHERS An organization composed of the greatest Cameramen of the Motion Picture World FEATURED IN THIS BOOK WILL BE A THOROUGH, ELEMENTAL COURSE IN CINEMATOGRAPHY Prepared by Professional Cameramen who have had years of experience This is designed to teach the AMATEUR the fundamentals of good cinematography in terms he can understand. Every step from scene to screen will be explained, with diagrams, formulas, tables, drawings and photographic illustrations. INNUMERABLE OTHER FEATURES will be found in this great book. First edition will be off the press in April. 1930. TO BE POSITIVE YOU GET YOUR COPY, place your order with your Book or Amateur Movie Supply Dealer NOW. The price is $5.00. If you prefer, fill out and mail the coupon below, with your check. American Society of Cinematographers, 1222 Guaranty Bldg., Hollywood, Calif. Gentlemen: Enclosed please find check (or money order) for Five Dollars ($5.00) for which please send me. postage prepaid, one copy of your Cinematographic Annual as soon as it is off the press, which date will be April, 1930. Name-Address City State