America's Munitions 1917-1918

by Benedict Crowell; United States. War Department

The forging for the 155-millimeter howitzer's recuperator is a block of steel weighing nearly 2 tons—in exact figures, 3,875 pounds. This must be bored and machined out until it weighs, with the accessory parts of the complete recuperator placed on the scales with it, only 870 pounds. It is scarcely fair to a modern hydropneumatic recuperator to say that it must be finished with the precision of a watch. It must be finished with a mechanical nicety comparable only to the finish of such a delicate instrument as a navigator's sextant or the mechanism which adjusts the Lick telescope to the movement of the earth. No heavy articles ever before turned out in American workshops required in their finish the degree of microscopic perfection the recuperators called for.

We adopted from the French, the greatest of all artillery builders, four recuperators—one for the 75-millimeter gun, one for the 155-millimeter gun, another for the 155-millimeter howitzer, and the fourth for the 240-millimeter howitzer. These mechanisms had never been built before outside of France. Indeed, one could find pessimists ready to say that none but French mechanics could build them at all and that our attempt to duplicate them could end only in failure. Yet American mechanical genius "licked" every one of these problems, as the men in the greasy overalls say, and did it in little more than a year of time after the plans came to the workshops. There was not one of these beautiful mechanisms, in France the product of patient handiwork on the part of metal craftsmen of deep and inherited skill, that eventually did not become in American workshops a practical proposition of quantity production.

The problem of building French recuperators in the United States, in short, may be regarded as the crux of the whole American ordnance undertaking in the war against Germany, the index of its success. It presented the most formidable challenge of all to American industrial skill. There were men whose opinion had to be considered and who were convinced that it was impracticable to attempt to produce French recuperators here. Although the superiority of these recoil devices in their respective classes were universally conceded, Germany had never been able to make them, while England, with the cooperation of the French ordnance engineers freely offered, did not attempt them. The French built them one by one, as certain custom-built and highly expensive automobiles are produced. When American factories proposed to produce French recuperators not only but to manufacture them by making parts and assembling them according to the modern practice of quantity production, the ranks of the skeptics increased.

Yet, as we have said, the thing was done. The first of these recuperators ever produced outside of the French industry were produced in America and manufactured by typically American quantity methods.

The first of these recuperators to come into quantity production was that for the 155-millimeter howitzer. Rough forgings began to be turned out in heavy quantities by the Mesta Machine Co. in the spring of 1918, while the Watertown Arsenal, the other contractor, reached quantity production in rough forgings in September, 1918. At their special recuperator plant at Detroit the Dodge Bros. turned out the first finished 155-millimeter howitzer recuperator in July, 1918, and went into quantity production with them in September, producing 495 in the month of November alone, and turning out up to the end of April, 1919, the great number of 1,601 of them.

Next in order of time to be conquered as a factory problem was the 155-millimeter gun recuperator. The rough forgings at the Carnegie Steel Co., the sole contractor, were in quantity production in the spring of 1918. The first of these recuperators finished came from the Dodge plant in October, 1918; and although 30 issued from the plant and were accepted before the end of the year, quantity production may be said to have started on January 1, 1919, when the factory began producing them at the rate of more than four a day. In March the high mark of 361 recuperators was reached, and the total production up to the end of April was 880.

The heavy 240-millimeter howitzer recuperator was third to come into quantity production. The rough forgings were being turned out in quantity in the spring of 1918 by the Carnegie Steel Co., while the Watertown Arsenal, the other contractor, produced a number of these rough forgings in August, 1918. The two contractors for finishing and turning out the complete recuperators were the Otis Elevator Co., at its Chicago plant, and the Watertown Arsenal. The arsenal produced the pilot recuperator in October, 1918. In January the Otis Elevator Co. produced its first four, while quantity production began in February, 1919, both contractors that month sending out 19 recuperators, a number which may be regarded as good quantity when the size of this mechanism is taken into consideration. Both plants together in April turned out the large number of 89 recuperators for the 240.

Last to come through to quantity production was the hardest of the four to build, the one that promised to defy American industry to build it at all—the 75-millimeter gun recuperator. The two contractors for the rough forgings for this recuperator were the Carbon Steel Co. and the Bucyrus Co. The Carbon Steel Co. was in large series production of them in the spring of 1918, and the Bucyrus Co. reached the quantity basis of manufacture in October, 1918. In that month alone both contractors together turned out 1,305 sets of forgings.

The machining and finishing of the 75 recuperator was in the hands of the Rock Island Arsenal and the Singer Manufacturing Co., which built a costly plant especially for the purpose at Elizabethport, N. J. The first recuperator of this size to appear and be accepted under the severe tests came from the arsenal in October. Thereafter the production ceased for a while. The contractors indeed built recuperators in this period, but the recuperators could not pass the tests. The machining and production of parts seemed to be as perfect as human skill could accomplish, but still the devices would not function perfectly. Adjustments, seemingly of the most microscopical and trivial sort, had to be made—there was trouble with the leather of the valves and with oil for the cylinders. These matters, which could scarcely cause any delay at all in the production of less delicate machinery, indicate the infinite care which had to be employed in the manufacture of the recuperators. At length the producers smoothed out the obstacles and learned all the secrets and necessary processes, and then the 75-millimeter recuperators began to come—2 in January, 1919, and then 13 in February, 20 in March, and 23 in April.

It should be remembered that by quantity production in this particular is meant the production in quantity of recuperators of such perfect quality as to pass the inspection of the Government and to be accepted as part of our national ordnance equipment. In this inspection the Government was assisted by French engineers sent from the great artillery factories in France which had designed the recuperators and which until the successful outcome of the American attempt were their sole producers. Such inspection naturally required that the American recuperators should be the equals of their French prototypes in every respect.