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October, 1920 THE MARINE REVIEW Reducing the percentage of defective castings results in 17% saving in machining costs LL manufacture began with the making of single articles on a one-at-a-time basis. One man usually performed every This loss is made up of three distinct forms of ex- cessive expense—(1) in lay- ing out of work, (2) in time required to cut away unnec- quired limitations. In actual shop-practice it is rarely practicable to apply such a method to detect flaws of this nature in advance of BETTER CASTINGS dry which operates Osborn Bet- Moulding Machines. 8 advantages favor the foun- 57 ter castings are not only as- essarily thick finish pads, and sured (which means continued operation. Each part of the finished article was made and adjusted to its single purpose. Eli Whitney is given credit for the idea of standardized production—at that time a revolutionary theory, because it meant that each worker specialized on a single pro- cess or part which, when completed, was in theory in- terchangeable with any other part produced at his bench or lathe. Without standardized pro- machining.- When the ma- re-orders from satisfied custo- mers) but eight savings enter into production costs. duction many of the greatest achievements of American industry would have been im- possible—the popular-priced automobile, the moderately- priced watch, the startling array of really usable hard- ware offered by the five-and- ten. cent store, and other striking examples. Standardized production— the repétition of exactly sim- ilar operations day after day at a speed which leaves unit production trailing far be- hind — accomplished the re- sult. Even today, however, many American manufacturers do not fully realize its possi- bilities. Apparently operat- ing on standardized produc- tion, they are, nevertheless, still blind to an opportunity which their competitors have seized. Castings are accepted and used which vary so greatly in uniformity and quality that any other piece of ma- terial would be instantly re- jected. This is not true of any other commodity. For instance, a slight vari- ation in the size or quality of cold rolled steel means in- stant rejection. However, some manufacturers tolerate castings which vary to a much greater degree. The result is an unneces- sarily high machining cost. (3) avoidable work or de- fective castings. In the large photograph ~ reproduced are two castings from the same pattern—one made by hand work, the other by machine-moulding. It is obvious that the right- hand casting may be mount- ed in a jig and rapidly cut down to the required dimen- sions. The smooth and reg- ular outline assures a uni- form cut—meaning less wear on the lathe and more speed. The machine method of pro- ducing castings assures both the smoothness and the uni- formity mentioned above. The contrast with its neigh- bor is startling. Uneven in outline, it is ap- parent that the depth of the shell of metal to be cut away varies greatly. The surface is irregular, pitted and of a texture that plays havoc with tools. The most dangerous fact of all, however, is shown in Fig. 2 which indicates by dotted line the required di- mensions of the finished cast- ings against the solid outline of the actual castings as re- ceived. Note how this test betrays that the left hand casting is actually defective. Machining will disclose that it does not fill out the re- chinist discovers such a flaw it is then too late to save the time he has wasted. Even though advance in- spection of every dimension is not practical, it is possi- ble to make a virtually com- plete elimination of this waste. Specify machine - moulded castings. Under machine-moulded production castings are strictly controlled to .0005 inch per inch of pattern draw. Variations such as are shown in the left-hand pho- tograph are eliminated. This extreme accuracy can not, of course, be accomp- lished by hand —it requires machines which have been accurately built. Faithful re- production of the pattern can be secured by the ma- chine only when slicking and patching of damaged moulds are entirely eliminated. This a machine can do— while a man can not. The result of this greater uniformity is best shown by actual production figures. Records obtained from machine shops which keep accurate casting costs show an average decrease of 71% in defective castings after the shift to machine-mould- ing and a 17% reduction in machining cost. IS BO: Machine moulding— 1. Insures rapid pro- duction. 2. Lowers direct mould- ing cost by multiply- mg man-power. 3. Accelerates delivery. 4. Saves metal. &. Reduces grinding and chipping. 6. Lessens pettern repairs. 7. Offsets labor ° shortages. &,. Reduces overhead per ton. Each of these eight points can be definitely supported by actual operating figures. Our sales engineers will come to you equipped to show you the reasons behind these facts and advise you as to an installation suitable for your needs. individual Catalog on request. THE OSBORN MANUFACTURING Lo, INCORPORATED CLEVELAND New York San Francisco Foreign Representatives: Allied Machinery Co. de France 9 Rue de Rocroy Paris, France J. W. Jackman & Co., Ltd. Caxton House, S.W. 1 Westminster, London, Eng, Horne Company, Ltd. 6 Takiyama-Cho, Kyokashi-Ku Toyko, Japan E. Isbecque & Cie, 36 Rue Otlet Brussels, Belgium Allied Machinery Co. d’Italia 40: Corso Dante Torino, Italy VN Please mention THE MARINE REVIEW when writing to Advertisers imi mimi mimi mmm mn MMMM