New Copper Sheathing

England’s Royal Navy began experimenting with copper-cladding its warships in the early 1760s and found it extended the life of the ships by preventing boring mollusks from destroying the wooden hulls. Below-the-waterline copper sheathing also allowed for greater ease in cleaning barnacles and crustaceans from ships’ bottoms. USS Constitution and the other five frigates of the original U.S. Navy were each copper-clad before launching, per the instructions of Joshua Humphreys, the frigates’ designer.

When coppered in the summer of 1797, Constitution‘s lower hull required “12,000 feet of sheet copper” and thousands of copper nails. There is no 18th century plan of the layout of the copper sheathing, but it is probable that the workers at Edmund Hartt’s shipyard began at Constitution‘s stern, down at the keel, and worked their way both forward and upward with row upon row of copper. Each sheet would have overlapped one inch on all sides, with the vertical joints between the sheets facing aft. This created a smooth “fish scale” affect to the hull, thereby preventing the sheets from being lifted by the action of the water. It is understood that the Royal Navy laid its warship copper with the horizontal joints facing upwards and it is possible that Constitution‘s copper was so installed, as depicted in the illustration below.

Two mid-to-late 19th century photographs of Constitution, hauled out of the water, offer the rare opportunity to observe, at close hand, the layout of her copper sheathing. Both the 1858 Portsmouth Navy Yard and the 1875 Philadelphia Navy Yard photos clearly show the “no belt” pattern to Constitution‘s copper.

As described by Mark Staniforth in his article “The Introduction and Use of Copper Sheathing – A History,” the “‘no belt’ copper pattern resulted from the greater distance from the keel to the waterline amidships than at either bow or stern. This resulted in a ‘bowed’ pattern where there were more rows of copper sheathing amidships and the rows curved sharply upwards at the bow and stern.” [From The Bulletin of the Australian Institute for Maritime Archaeology, Vol. 9, No. 1 of 2, 1985, 30]

 

For the 1927 restoration, a plan was drawn of the proposed layout for the new copper sheathing. Lieutenant John A. Lord’s “U.S. Frigate Constitution Copper Plan,” #25002, dated December 12, 1929, shows an outboard profile of the ship with perfectly straight lines superimposed on the lower hull, representing the lines of copper sheathing. Given the extreme curves to Constitution‘s lower hull, it is nearly impossible to lay the sheathing in perfectly parallel rows.

When examining photographs of the newly coppered Constitution in the spring of 1930, it appears that the Navy re-coppered Constitution using the “goring belt” method.  Staniforth’s description is thus: “The…’Goring Belt’ copper pattern was developed in order to overcome the problems which the shape of the hull caused. Certain sheets of copper were cut to fit the triangular section at both bow and stern where the rows of copper sheets were not parallel to each other.” [Staniforth, 30] The March 31, 1930 photograph of “Old Ironsides” in Dry Dock 1, just before her undocking, clearly shows the areas where copper sheathing was cut into various triangular shapes to fit the curves of the vessel’s hull.

USS Constitution was re-coppered in the 1973-1974 dry docking and again in the 1992 restoration. Each time, the pattern of laying the sheathing on the ship’s lower hull has essentially followed the “goring belt” method established in the 1927 restoration. And, at least since the 1973-1974 re-coppering, the uppermost two rows or so of copper have been covered with red anti-fouling paint, to prevent any marine growth right at the ship’s waterline.

For the 2015-2017 restoration, the ceremonial “first piece” of copper sheathing was removed from Constitution‘s rudder on June 9, 2015, just three weeks after the ship had been dry docked. Even though much preparatory work was begun on the ship before she left the water, the removal of that first piece of copper marked the “beginning” of the 2015 – 2017 dry docking and restoration.

 

The summer and autumn of 2015 saw the removal of nearly 2,500 sheets of copper from the lower hull. Beginning in mid-October, Naval History & Heritage Command Detachment Boston ship restorers and a group of USS Constitution sailors began installing the new copper sheathing.

As part of the current restoration, visitors to the USS Constitution Museum have the opportunity to actually leave their “mark” on history. The Museum and NHHC Detachment Boston, with the help of the crew of Constitution, have provided a once-every-twenty-years chance for visitors to sign their names to copper sheathing. To date 425 sheets have been signed since the ship docked in May, 2015.

Before the copper sheets are installed on the ship’s lower hull, they have to be individually perforated so that the small copper nails can be driven through the copper sheet and into the white oak hull planking. The hand-cranked copper punching machine that is used was patented in 1852!

 

The signed copper sheets are currently being installed.  The first one was attached to the ship’s keel on the port side. Another signed piece was attached to the rudder, filling the spot where the ceremonial “first piece” was removed nearly 18 months ago.

The coppering of the port side of USS Constitution is nearing completion. The caulking of the starboard side is almost finished and the coppering of that side of the ship’s lower hull will soon begin. By the time Constitution is un-docked in the mid-summer of 2017, 2,200 of the 3,200 sheets that cover the bottom of the ship will have been replaced.

 

USS Constitution‘s original keel and very bottom hull planking have survived for 219 years in part because they have been protected by copper sheathing. The U.S. Navy’s commitment to keeping Constitution “copper bottomed” should guarantee the life of the ship’s backbone for many more years to come. Souvenirs made from copper removed from USS Constitution are available at the USS Constitution Museum Store, including jewelry and limited edition copper medallions.

 

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The activity that is the subject of this blog article has been financed in part with Federal funds from the National Maritime Heritage Grant program, administered by the National Park Service, U.S. Department of the Interior, through the Massachusetts Historical Commission, Secretary of the Commonwealth William Francis Galvin, Chairman. However, the contents and opinions do not necessarily reflect the views or policies of the Department of the Interior, or the Massachusetts Historical Commission, nor does the mention of trade names or commercial products constitute endorsement or recommendation by the Department of the Interior, or the Massachusetts Historical Commission.

The Author(s)

Margherita Desy, Historian, Naval History and Heritage Command Detachment Boston
Historian, Naval History and Heritage Command

Margherita M. Desy is the Historian for USS Constitution at Naval History and Heritage Command Detachment Boston.

Phaedra Scott
Content Developer, USS Constitution Museum

Phaedra Scott was the Content Developer at the USS Constitution Museum from 2016 to 2017.

Kate Monea
Manager of Curatorial Affairs, USS Constitution Museum

Kate Monea is the Manager of Curatorial Affairs at the USS Constitution Museum.