Fort Pitt Foundry

The Fort Pitt Foundry: A Pioneer in Cannon Manufacturing

The Fort Pitt Foundry holds a significant place in the history of iron foundries and cannon manufacturing in the United States. Established in 1804 in Pittsburgh, Pennsylvania, by Joseph McClurg and his son Alex McClurg, the foundry played a crucial role in supplying cannons and cannonballs to the U.S. military during the War of 1812. Over the years, the Fort Pitt Foundry pioneered advancements in casting techniques, bore cooling, and the production of large-caliber guns. This article delves into the fascinating history of the Fort Pitt Foundry, exploring its contributions to the military and its impact on the development of artillery.

Origins and Early Years

The Fort Pitt Foundry was initially located at Fifth Avenue and Smithfield Street in Pittsburgh. It started its operations in 1804, manufacturing cannons and carronades for the U.S. Navy under a contract with the Secretary of the Navy. At that time, most cannon boring machinery in the United States was driven by water power. However, due to the absence of convenient waterfalls near the foundry and limited knowledge of steam power in the western region, the McClurgs opted to use horse power to drive their boring mill.

In 1815, the foundry and boring mill were passed down to Joseph McClurg’s sons, who secured a contract with the Secretary of War for the production of cannon shot and shells. The foundry moved to the Strip District at 12th and Etna, where it continued its operations. At that time, the largest cannon manufactured by the Fort Pitt Foundry was the 24-pounder, weighing approximately 5200 pounds. In 1829, the foundry cast its first 32-pounder, followed by the introduction of a 42-pounder in the subsequent years.

Advancements in Gun Manufacturing

Introduction of Experimental Shell Guns

In 1839 and 1840, Colonel George Bomford, Chief of Ordnance, ordered the casting of experimental shell guns at Alger’s foundry in Boston. These guns, including 64-pounders with an eight-inch caliber and a 125-pounder with a ten-inch caliber, were designed to test the feasibility of firing shells from long guns. The trials conducted in 1840 and 1842 showed that large, heavy guns could be loaded and fired with ease, and heavy shells could be safely fired with accuracy and range. This marked a significant development in artillery technology.

The Rodman Gun and Hollow Casting

Fort Pitt Foundry

Lieutenant Rodman, later General Rodman, played a pivotal role in revolutionizing the casting of cannons. In 1845 and 1846, he supervised the casting of a series of eight-inch guns at the Fort Pitt Foundry. Recognizing that the traditional method of cooling solid cast guns from the exterior could potentially compromise their quality, Rodman proposed casting the guns hollow and cooling them from the interior. This innovative approach aimed to reverse the direction of strains and increase the gun’s resistance to internal forces.

To test this theory, two eight-inch guns were cast in 1849 at the Fort Pitt Foundry, one solid and the other hollow. Both guns underwent continuous alternate firing with equal charges of powder and shot until they broke. The hollow cast gun endured approximately three times the number of fires compared to the solid cast gun, demonstrating the superior durability and safety of the hollow casting method.

Further trials were conducted in 1851, involving the casting and testing of ten-inch guns. The results reinforced the superiority of hollow cast guns, with the solid cast guns breaking after 72 fires, while the hollow cast guns endured over 1500 fires without any visible damage. Subsequent trials in 1856 and 1857 further substantiated the benefits of hollow casting, paving the way for its adoption as the standard practice for heavy guns manufactured for the War Department.

Introduction of Larger Calibers

In 1859, an important development took place with the successful casting of a fifteen-inch gun at the Fort Pitt Foundry. Designed by Captain Rodman, this gun weighed approximately 49,000 pounds and was 16 feet long and 49 inches in diameter. Extensive trials were conducted at Fort Monroe, where the gun was fired 500 times with varying charges of powder and shells weighing 300 to 330 pounds. The exceptional performance of the fifteen-inch gun in terms of durability, maneuverability, and destructive power led to its adoption for naval and land-based fortifications.

Buoyed by the success of the fifteen-inch gun, Captain Rodman proposed the manufacturing and testing of a twenty-inch gun in 1861. However, due to the outbreak of the Civil War and the subsequent demand for resources, the proposition was temporarily put on hold.

The Fort Pitt Foundry’s Legacy

The Fort Pitt Foundry’s contributions to cannon manufacturing and artillery technology were unparalleled during its time. The pioneering work in hollow casting and bore cooling techniques revolutionized the field, ensuring stronger, more durable cannons capable of handling heavy charges and firing large shells. The adoption of larger calibers, such as the fifteen-inch gun, further solidified the foundry’s reputation as a leader in the industry.

The legacy of the Fort Pitt Foundry extended beyond its technical achievements. The foundry’s location in Pittsburgh, a burgeoning industrial center, allowed it to leverage the region’s rich iron ore deposits and skilled workforce. Its ability to adapt to advancements in manufacturing techniques, such as the introduction of steam power, enabled the foundry to meet the increasing demands of the military.

Unfortunately, the Fort Pitt Foundry’s operations came to an end after the Civil War. In 1878, it was sold to a rival company, marking the end of an era. Nevertheless, the innovations and advancements pioneered by the Fort Pitt Foundry continue to influence the field of artillery manufacturing to this day.

Fort Pitt Foundry

The Fort Pitt Foundry played a pivotal role in the development of cannon manufacturing in the United States. From its early years supplying cannons to the U.S. military during the War of 1812 to its groundbreaking advancements in casting techniques and bore cooling, the foundry left an indelible mark on the field of artillery. Its introduction of experimental shell guns, the adoption of hollow casting, and the production of larger calibers set new standards in durability, safety, and destructive power.

Today, the Fort Pitt Foundry’s legacy lives on as a testament to the ingenuity and innovation of the early pioneers in the field of artillery manufacturing. The techniques and advancements developed at the foundry paved the way for future developments in the field. The Fort Pitt Foundry’s contributions continue to be recognized as a significant chapter in the history of American industry and military technology.