When thinking of USS Constitution‘s restorations, it’s easy to focus on the more heroic projects, like rebuilding the cutwater, replacing the hull planks, and recoppering. Equally necessary to the ship’s longevity, however, are the little known, behind-the-scenes tasks that make the bigger projects possible. Throughout the restoration, Naval History & Heritage Command Detachment Boston ship restorers are busy rolling oakum, caulking, repairing rigging, and refurbishing furniture for “Old Ironsides.”
Traditionally, hull and deck seams of wooden vessels have been packed with cotton batting and oakum to prevent leaks. Oakum is historically made from hemp fibers that are lightly tarred to help make the material rot resistant. An individual vessel of the size of USS Constitution would use thousands of feet of cotton batting and oakum. For example, in 1820, Amos Binney, the Naval Purchasing Agent in Boston, advertised to purchase 20,000 pounds of oakum to be used at the Portsmouth Navy Yard, Kittery, Maine.
For Constitution‘s current restoration, all of the caulking below the waterline and in between new hull planks is being replaced. The oakum is delivered in tightly packed bundles of fibers and must be unraveled, picked clean of grass and debris, fluffed, and rolled into long strands. The cotton batting is delivered rolled and ready to be used. Visitors to the USS Constitution Museum can try their hand at caulking in our daily hands-on programs.
The caulking process begins with several strands of cotton batting driven deep between the planks using a caulking iron and mallet. Next, several layers of oakum are similarly driven into the seams. The caulking mallet has evolved into a uniquely designed ship building tool with a cylindrical head of a hard wood, banded with iron at either end to prevent the head from splitting. The handle is in similar proportion to the head, allowing the caulker to swing the mallet with ease for long periods of time regardless of the angle at which the caulking is being driven into the ship.
When a ship enters the water, the hull planks will swell, but not enough to prevent the ship from leaking. Cotton batting and oakum are used to make the ship water tight. Cotton batting is driven into the seams first because it expands quickly when wet. However, it is not very rot resistant and therefore cannot make up the whole of the ship’s caulking. Oakum, on the other hand, is more rot resistant but does not swell as rapidly in the seams. The two fibers are used in tandem to create a perfect seal between the planks. Tar was historically applied to finish off the seams. Today, a rubberized marine sealant is used in lieu of tar.
USS Constitution‘s upper masts and yards were down-rigged prior to entering dry dock in May 2015. The rigging is currently being overhauled and repaired in NHHC Detachment Boston’s rigging loft. Beginning in the 1960s, Constitution‘s rig was no longer made of natural fiber line. Today, her standing rigging is made of spun polyester and her running rigging is made of fibrillated polypropylene yarns. The modern synthetic lines offer greater strength, durability, and are more resistant to acid rain and the sun’s damaging ultra-violet rays. While the ship is down-rigged, the NHHC Detachment Boston riggers are surveying all of the rigging to determine what needs to be repaired or replaced.
USS Constitution‘s live oak frames above the waterline were completely replaced in the 1927-1931 restoration. In the intervening decades, the ship’s hull planking has been replaced many times. Each time a plank and its fasteners are removed, fastener holes are left in the frames. The holes are subsequently filled with oak plugs prior to the installation of the new plank to maintain the structural integrity of the frames.
For USS Constitution‘s 1931-1934 three-coast National Cruise, the ship was fully outfitted with furniture for the 81 officers and crew on board. The well-known Paine Furniture Company in Boston manufactured a variety of pieces for the ship during the 1927-1931 restoration, including the mahogany cabin lounge for the Captain’s After Cabin. Originally, the lounge was upholstered in dark brown leather and the cushions filled with horse hair. While not an exact replica of Federal era (1785-1825) furniture, the lounge displays motifs reminiscent of the period. Notably, the delicately carved swagged drapery on the lounge’s crest rail and the pierced support under the armrest are nods to the Federal era.
The original upholstery is long gone. For the current restoration, the lounge cushions were restored by Dynasty Auto Tops & Upholstery company in Revere, Massachusetts. Dynasty Upholstery retied the springs, refilled the cushions with cotton batting, and covered them with a brown, leather-like vinyl. The damp atmosphere of the ship precludes using real leather, which rots too quickly.
Margherita M. Desy
Historian, Naval History & Heritage Command
Margherita M. Desy is the Historian for USS Constitution at Naval History and Heritage Command Detachment Boston.
Manager of Curatorial Affairs, USS Constitution Museum
Kate Monea is the Manager of Curatorial Affairs at the USS Constitution Museum.