The Old Erecting Shop
321 Arsenal Street (AKA Building 312)
Building 312 was built in 1894 to construct new, larger carriages for 8-, 10- and 12-inch guns and field mortars. It was part of the original Seacoast Gun Carriage Complex. In 1917, Building 312 became a heavy machine shop. Its large, open workspace and high ceilings were ideal for building the large machining tools needed for the 14- and 16-inch gun carriages, including the massive 41-foot Gleason gear cutter, one of the largest of its kind in the world.
In 1960-61, the large machine tools were replaced with laboratories conducting metals and ceramics research for the Army Materials Research Agency. Projects included developing new techniques for growing synthetic sapphire crystals, using shock wave testing to determine the strength and tolerances of various metals, and building a gas-powered ballistics range.