Today was a major milestone in the effort to conserve USS Monitor’s amazing artifacts. Almost 147 years after the iconic ironclad sank, conservators rotated the port gun carriage to its original upright position.
USS Monitor’s two custom-built gun carriages have been upside down since the ironclad sank on December 31, 1862. The gun carriages were discovered by archaeologists during excavations of the turret in 2002. The carriages were still secured to the 8-ton Dahlgren guns they supported during the Battle of Hampton Roads. Conservators and archaeologists carefully removed both carriages from the turret in 2004.
The carriages, designed by John Ericsson, were built to allow safe use of the guns within the tight confines of the revolving gun turret. These carriages moved on massive iron gun rails bolted to the turret floor.
Conservators have been actively treating the gun carriages since their removal from the turret. The carriages are extremely difficult to treat because they are composite artifacts. Composite artifacts are made from many different materials types that require individual and sometimes incompatible treatment needs. Monitor’s carriages are made of wrought iron, various copper alloys, and thick structural wooden frames wrapped in iron. The conservation department will disassemble the gun carriages into their component structures and materials for individual treatment.
Conservators must rotate both gun carriages to their original upright position in order to gain access to the complex braking mechanism and facilitate continued treatment. Artifact handler and 10-year Monitor project veteran Gary Paden and other conservators spent weeks designing and custom-fabricating epoxy-coated steel lifting and rotation rigs that allow the conservation staff to rotate the carriages without placing undue physical strain on their fragile surfaces.
This morning conservators attached the special rig to the underside (current top) of the port carriage and removed the carriage from its treatment tank. Conservators used a 20-ton hoist to lift the carriage in the air and attach the assembly to a steel A-frame with a pivot mount. The crane then lifted the carriage and pivoted the entire assembly over the A-frame until the carriage reached its original upright position, much like a door pivoting on a hinge. The rig was then removed from the carriage, and the conservation team returned the carriage safely to its treatment tank. Conservators spent an additional 2 hours removing concreted sediment from the carriage’s braking assembly and revealed many interesting archaeological details.
Conservators will rotate the starboard carriage to its original upright position between 9am and noon EST tomorrow morning (Nov. 10, 2009). Join us at the Batten Conservation Facility in the USS Monitor Center at The Mariners’ Museum in order to see the action live, or visit us on the web and see things unfold via the magic of our webcams (http://ww2.marinersmuseum.org/exhibitions/ussmonitorcenter/camera.php).