The Lupton plant had difficulty in securing the heavy machinery it needed for this and for other mortar contracts, its machinery being held up by the freight congestion. Early in 1918 the American Expeditionary Forces advised us to redesign the 240-millimeter mortar to give it a stronger barrel. Consequently all work was stopped until this could be done. The first mortars of the new design to be tested were still unsatisfactory with respect to the strength of the barrels; and as a consequence the Standard Forging Co. urged that nickel steel be substituted for basic open-hearth steel as the material for the barrels. This change proved to be justified.
There was also trouble at the shops of the American Laundry Machine Co., its equipment not having the precision to do machining of the type required in these weapons. Accordingly a new machining contract was made with the Symington-Anderson Co., of Rochester, N. Y., which concern was eventually able to reach a production of 20 machined barrels per week.
In all we produced 24 of the 240-millimeter mortars in this country. Certain of the parts were manufactured up to the total requirements of the contracts, but others were not built in such numbers. The International Harvester Co. built all 999 carts ordered.
The production of shell for these big mortars was another difficult undertaking. After consultation with manufacturers we designed shell of two different types. One of these was a shell of pressed plates welded together longitudinally; and a contract for the production of 283,096 of these was placed with the Metropolitan Engineering Co. The other form was that of two steel hemispheres welded together. The Michigan Stamping Co., of Detroit, undertook to build 50,000 of these.
These shell contracts were placed in December, 1917. The Michigan Stamping Co. had to wait five months before it could secure and install its complete equipment of machinery. It was September before all of the difficulties in the Detroit plant's project could be overcome and quantity production could be started. The concern eventually, before and after the signing of the armistice, built 9,185 shell of this type at a maximum rate of 56 per day.
Greater promise seemed to be held forth by the Metropolitan Engineering Co.'s project to build shell of pressed-out plates, electrically welded. The Government undertook to furnish the steel plates for this work and secured from the American Rolling Mills Co., of Middletown, Ohio, a total production of 6,757 tons of them. The Metropolitan Engineering Co. had great difficulty in perfecting a proper welding process; and the concern lost a great deal of money on the contract, yet cheerfully continued its development without prospect of recompense in order that we might have in this country the knowledge of how to build such shell. In all, including production after the armistice was signed, the Metropolitan Engineering Co. built 136,189 shell bodies of this size at a maximum rate of 987 per day.
During the summer of 1918 a single-piece shell body of the 240-millimeter size, produced by a deep-drawing process, was worked out. A contract for 125,000 of them was given to the Ireland & Matthews Manufacturing Co., of Detroit, Mich. The armistice brought this contract to an end before it had produced any shell of this new and most promising type.
Early in 1918 we received the first samples of the 6-inch trench mortar. By April all the plans were ready for American production. Again this work was divided by types. The National Tube Co., of Pittsburgh, contracted to build 510 rough forgings of mortar barrels at its Christy Park plant. The Symington-Anderson Co. undertook to machine these barrels. The David Lupton Sons Co. agreed to assemble the mortars, as well as to produce the metal and timber bases for them.
The first machined barrels reached the Lupton plant in June and found bases ready for them. But, as the assembling was in progress, the American Expeditionary Forces cabled that the British producers of mortars had changed their designs, and that we must suspend our manufacture until we also could adopt the changes. The altered plans reached us some weeks later; yet, nevertheless, we were able to make good our original promise to deliver 48 of the 6-inch Newton-Stokes mortars at the port of embarkation in October, 1918.
Meanwhile we had increased the contracts by an additional requirement of 1,577 mortars of this size. The National Tube Co. eventually reached a maximum daily production of 60 barrel forgings. The Symington-Anderson Co. machined the barrels finally at a 33-per-day clip. As many as 11 proof-fired guns per day came from the David Lupton Sons Co.