Prior to the American Civil War the United States had shown no interest in producing ironclads. Although, Great Britain and France were already engaged in a building race in the construction of bigger and bigger seagoing armored ships, the United States was content with its small wooden fleet. The biggest and most capable were the big screw frigates of the Merrimack class authorized in 1854. The Merrimack was immobile at the shipyard at the Gosport Navy Yard in Norfolk, Virginia when Confederate forces moved in to seize the yard. Merrimack could have been moved to safety to a northern yard when Virginia seceded from the Union on April 17, 1861 but through botched orders the opportunity was missed. On April 20 any ship that could not be evacuated was burned, including the big Merrimack. Stephen Mallory, the Secretary of the Navy for the Confederacy had placed orders for ironclads from the very start of the war. In this regard the Confederacy was far ahead of the United States Department of the Navy. Mallory immediately ordered the Merrimack raised and converted to an ironclad. Construction was well underway by July.
Meanwhile, there was no sense of urgency in the North. Only after rumors of the Confederate plans for the Merrimack filtered north did the Union start to address the acquisition of ironclads. On August 3, 1861 Congress ordered the Navy Department to select a three-officer board to examine the possibility of acquisition of Union ironclads. Known as the Ironclad Board, Congress apportioned $1,500,000 for construction of any ironclads selected by the board. When the board solicited proposals, about the only requirement was for vessels to have a shallow draft of between ten to sixteen feet. This of course was to allow the ships to operate in rivers and estuaries. The board received 16 proposals but only three were selected, one of which was the unconventional Monitor. By October it finally dawned on the Navy that the Confederate ironclad conversion of the Merrimack was going to be a reality. Only then did they develop a sense of urgency. As Monitor was the only vessel that could be completed reasonably quickly, the contract for Monitor required completion within 100 days. Monitor was completed before the CSS Virginia, as Merrimack was renamed.
On March 8, 1862 CSS Virginia left port for what was thought to be a trial. Instead, she made for the wooden USN squadron blockading Norfolk. The death of the USN wooden navy came quickly as Virginia quickly sank the sloop USS Cumberland and the frigate USS Congress. The USS Minnesota, a sister to the Merrimack, ran aground while trying to avoid her former sistership. It was late so Virginia returned to port with the intent of finishing off the Minnesota the next day. On the 9th Virginia left to complete the destruction of Minnesota but soon discovered that the Monitor, which had arrived on the night of the 8th, was protecting Virginiaís intended victim. After the two ironclads fought to a draw, it was clear to all future warship construction would have to concentrate on ironclads.
In contrast to the hesitation and heel dragging displayed by the Ironclad Board in 1861, the board eagerly snatched up almost any reasonable and some outlandish ironclad designs. Having received a great shock by the initial success of Virginia, Congress opened up the purse strings to purchase a fleet of ironclads. Of course a bulk of the new construction were variations of the successful Monitor design but other, very different designs were built as well. One such design would become the largest and heaviest warship built in the United States up to that time. This unusual ship was the USS Dunderberg.
The Dunderberg was designed by John Lenthall and built by W.H. Webb of New York City. The design had far more in common with Confederate ironclad designs than with other northern designs. Like almost all southern ironclads it was designed with a long casemate gun deck. The original design did have two turrets but these were eliminated from the final design, which was accepted for construction in July 1862. The Dunderberg was laid down in October 1862. She was very heavily armed with two 15-inch and eight 11-inch Dahlgren smooth bore cannons, the two primary guns used by the USN during the war. During construction two more 15-inch and four more 11-inch guns were added to the design. As with southern casemate ironclads, the Dunderberg had a very low freeboard with bottom of the gun ports being only four feet eight inches above the waterline. The hull was built with wood with iron plates attached onto the wooden frame. At the knuckle, where the casemate met the hull, the thickness of the wooden backing was 7 Ĺ feet, although in other areas the wooden frame was 3 feet in thickness. The hull received an iron belt that ranged from 3 Ĺ to 2 Ĺ inches in thickness. The armor on the casemate was 4 Ĺ inches thick. Also, like Confederate ironclads, the Dunderberg was built with a heavy, prominent ram. The ram was a solid fifty-foot piece of oak sheathed in iron. She was equipped with two horizontal engines, which drove a single shaft and were to develop 4,500 shp for a designed maximum speed of 15-knots. Six boilers fed steam to the engines.
On paper the design was an impressive ship, fast, heavily armed and heavily armored. However, reality was far different. In an effort to speed completion of the ship, green, unseasoned wood was used for the wooden framework and backing, rather than seasoned timber. It would have been far better to have seasoned the wood first because the builder did have the time to do so. The problem with using green wood is that rots far more quickly than seasoned wood and is far more subject to insect infestation. The construction of the Dunderberg was greatly slowed due to lack of other critical materials. Iron was needed for army artillery as well as for navy artillery, armor and machinery. During construction Dunderberg was equipped with a number of advanced features. She had a double bottom, collision bulkhead, watertight bulkheads, and armored gratings in the funnel to prevent debris from entering. In addition to her two engines, she was also given a light brigantine sail rig. Dunderberg was not launched until July 1865, just after the war had ended. Trials were held in 1867 and showed a maximum speed of 11.7-knots at 3,778 shp, far below contract figures. This gave the government a chance to refuse the ironclad. Webb took back the ship and refunded $1,041,660 of the $1,250, 000 that the government had paid the company for the Dunderberg.
Webb was now saddled with an expensive ironclad and quickly sought foreign buyers. Fortunately for the company, they found a ready purchaser. France was still building ironclads but was falling behind Great Britain. France saw the Dunderberg as an opportunity to cut down in the disparity of numbers. The ship was purchased and renamed the Rochambeau after the French General who had commanded the French troops dispatched to America to aide the United States in the American Revolution. This was the general that the British tried to surrender to at Yorktown in the belief that it was more honorable to surrender to a French general than to George Washington.
The French didnít need muzzle-loading smooth bores and rearmed the ship with four 10.8-inch and ten 9.4-inch breach-loaders. On their trials in 1868 the French Navy claimed that Rochambeau made 15.07-knots at 4,535shp. This of course gives rise to the question of whether the French inflated the numbers in order to magnify the capabilities of their purchase or the USN cooked their tests to allow them the opportunity to refuse acceptance of Dunderberg and stick the builder with the expense. The only time the Rochambeau was placed in commission with the French Navy was during the Franco-Prussian War in 1870 and she served in the Baltic in an attack on Kolberg. By 1872 the green wood hull and framing was decaying and the ship was stricken after only five years since her first trials. The ship was finally scrapped in 1874. One other interesting aspect of the Dunderberg was that the machinery for the ship was produced by John Roach of Chester, Pennsylvania. In 1883 the Roach shipyard was given the contract for the first four ships of the new American Steel Navy but then Roach was driven to bankruptcy by subsequent governmental shenanigans and refusal to pay, reflecting back to the events of the Dunderberg. (History from The Complete Encyclopedia of Battleships, 1983 by Tony Gibbons; Conwayís All the Worldís Fighting Ships 1860-1905, 1979; Warships and Naval Battles of the Civil War, 1989, by Tony Gibbons)
The Combrig Dunderberg
Combrig produces a large under of unusual subjects but the ironclad Dunderberg / Rochambeau has to rank as one of the most unusual. The shipís main claim to fame is that she was the largest and heaviest warship built in the United States up to that time. She was only three feet shorter with three feet less beam than the Royal Sovereign class of 1890. Of course she drew less water and had almost no freeboard. Her voyage to France must have been in good weather. With almost every American Civil ironclad there is no superstructure, although I guess the casemate could qualify as such. With a hull 6 5/16th-inch long and a width of 1 ľ inch at the widest point in the knuckle, the hull casting is surprisingly large for an ACW ironclad. The sides of the hull have a reverse tumblehome in that the hull widens as it gets higher. There are many unusual hull features that will set this model apart from almost anything else. At the bow is a very pronounced ram. The forecastle slopes downward as it approaches the cutwater. If anything it resembles the hooked beak of an eagle or falcon. Two features dominate the hull sides. One is the very sharp knuckle where the hull sides meet the casemate. According to sources the casemate armor slanted inboard at a 35-degree angle. I didnít measure it with a protractor but the angle looks right with the Mk I eyeball. The other prominent features are the rows of gun ports. These ports are significantly recessed from the casemate sides and are not square in shape. The base of each port is significantly wider than the top of the port.
The stern is also unusual. There is an open area under the stern, which appears to be a shroud for the propeller and rudder. With the aft end of the quarterdeck overhanging the area and armored bulkheads sloping upward from the water line to the point of the stern, it seems that this feature was designed to provide shot protection to the propeller and rudder area. The fore and aft faces of the casemate are a series of angular plates that as a whole have a more rounded appearance than commonly found in casemate ironclads. At the time it was far easier to build an ironclad with flat plates than with curves. Almost all Confederate ironclads, Virginia excepted, had flat surfaces fore and aft as well as the sides because they were easier to produce with their rudimentary ship-building industry. The plan view reflects a smooth, uncluttered appearance. Fittings of any height would be quickly shot away with your own guns in this era, so what deck fittings do appear are low on the deck. At the forecastle there appears to be an access hatch, two sets of bollards and a skylight. On the quarterdeck there is another access hatch, skylight and four sets of bollards. There is one other feature on the quarterdeck. Two rows of seven holes or scuttles parallel each other about half way out from centerline. I assume that these are coal scuttles but that is just a guess based upon their appearance and location. The greatest number of fittings are on the upper deck above the casemate. Five appear to be small access coamings or ventilation louvers. The largest fittings are clearly ventilation grills fore and aft of the stack base. The stack base itself appears as an armored apron slanting inward on all four sides as it rises. Just in front of this is a circular conning tower. Amidships at the edge of the upper deck on each side are what appear to be solid bulkheads.
Smaller Resin Parts
The largest of the smaller parts is the stack. At the base of the stack is an apron. It is supposed to be there so donít remove it. The instructions show a rectangle underneath the apron that is to fit in the stack recess of the hull casting. That rectangle is not on the stack piece. Accordingly youíll have to adjust the position of the stack to square it up with fitting below. This is a good place to use white glue in order to give you time to make the positioning adjustments. The stack has a single band line and the top is hollow to about 1/8 inch. Four shipís boats are provided, which overhang the sides of the casemate on davits. On the runner with the davits are also found two small anchor cranes. Other separate deck fittings are two anchors and seven small funnel ventilators, which all go on the upper deck. One runner contains both masts, as well as the yards and booms. Note that the foremast is the taller of the two masts. The last runner contains three parts, a windlass for the upper deck, the top of the rudder for the recess at the stern and a top for the foremast. All three parts are very well detailed, especially the top, which even has lubber holes in the platform.
Sails are another source for extra detail. You donít have to have the Dunderberg under sail, as she probably used steam most of the time. However, Dunderberg under sail would add a further unusual twist to an already unusual model. I donít know of any ready-made source for these items. Probably the best solution would be to vacuform sails from a plastic model of a sailing ship and cut them to shape. Unfortunately, not that many modelers have access to a vacuform these days. It would be easier by far to depict the sails furled on the yards. This would not be too hard as card stock could be cut to fit the yards and the width of each furled sail built up with layers of white glue. You could use a toothpick to scribe furls in the sails. One other addition would be photo-etch railing. The profile in the instructions shows three rung rail on the Dunderberg. The railing on the upper deck is at the edge of the deck and top of casemate, however, the railing on the forecastle and quarterdeck is located substantially inboard from the sides of the hull. The inboard railing will also make the Combrig Dunderberg very distinctive. Placement of the railing can be determined by the plan view provided on the instructions.
The instructions for the Combrig Dunderberg is in the standard Combrig format. There is one back-printed sheet included with the kit. The front side shows a 1:700 scale plan and profile. Normally reference to the printed plan and profile in Combrig instructions is essential to get proper placement of many parts but with this kit it is far less so. They can help with the exact location of shipís boats and davits but about everything else is very easy to place. However, the plan and profile are still extremely valuable for rigging, ratline placement and railing placement. Also found on the front are the shipís statistics in Russian and a history of the ironclad in Russian and English. The reverse has a photograph of all of the parts in their actual size and a single isometric view of assembly. The assembly drawing is very easy to follow, as the parts count is rather low. It is hard to go wrong on this model.
Combrig has produced a very unusual but fascinating model. Their 1:700 scale Dunderberg is a replica of the largest ironclad produced during the American Civil War. An additional attraction is that if you wish to attack Kolberg, you can model the French Rochambeau. The model is easy to build but offers a platform for layers of extra detail. If you like the odd and bizarre, the Combrig Dunderberg is for you.