Two pressures created Drydock II. The first was a patent. The Rederij der Drijvende Droogdokken held the exclusive Dutch licence to operate floating dry docks, but only until December 1846. Renewing it would require demonstrating that the market was being properly served - and a single dock in the Oosterdok, the older of Amsterdam's two great wet basins, was not enough. The second was geography. Ships moored in the Westerdok could in principle be towed across to the Oosterdok dock, but the cost of moving them was significant, and any competitor who set up in the Westerdok would have an obvious selling point. The Rederij decided to build a sibling dock and put it where the Oosterdok one was not. By August 1844 the decision was public; the new dock was to be moored in the Westerdok, the wet basin on the western side of the IJ.

The design lineage runs through New York. In 1839-1840, an American inventor named John S. Gilbert - the inventor of the balance dry dock - built a wooden floating dry dock at the port of New York. Amsterdam's first dock, opened in November 1842, was based on Gilbert's design. Drydock II was an almost exact copy of Drydock I. The dimensions are nearly identical: 49.50 metres long, 18.70 metres wide, 6.50 metres deep in the hold, drawing 1.20 metres of water with 240 last of ballast (a Dutch last being about two thousand kilogrammes). Only the length and draft differed marginally from its older sibling. Because the new dock was wider than the lock connecting the Westerdok to the outer harbour, it could not have been towed in from elsewhere; it had to be built inside the basin by a shipyard already working there. A clean piece of confined-space engineering, executed twice.

By 1858 the Westerdok was something of a showpiece of mid-century Dutch industry. When the Royal Institute of Engineers visited that September, their tour included the Amsterdam Gas Factory, the Holst and Kooi rope walk, the De Atlas machine works, the steam sugar refinery, and Drydock II - the dock listed alongside heavy industry as a peer. In 1859 the marine painter Johan Conrad Greive sketched the dock with the frigate De Javaan riding high in its cradle, a 736-tonne East Indies-built ship under Captain H. Munnix that had just arrived from Batavia. The Javaan was politically loaded cargo: a working argument for whether the Dutch should keep building naval vessels in the East Indies rather than shipping them from home. A few years later, in January 1861, she ran aground near Egmond aan Zee on a return voyage, got herself free, and was offered for sale that March in the Oosterdok. The Westerdok dock served plenty of less famous ships in between. The painter Kaspar Karsen captured the dock around 1860 in a canvas of the Westerdok that also shows the sugar refinery looming behind it.

By 1890 the small-ship dry-dock market was saturated, and the Rederij sold the dock for break-up. On 16 June 1890 the Westerdok Wooden Drydock - everything except the boiler - went under the hammer alongside two carpenter rafts, a rowboat, and four spars. The lot fetched 2,549 guilders. The deal collapsed; a second auction had to be scheduled for 7 July, then postponed to 14 July. Eventually the dock came apart. On 7 August buyers were offered large quantities of oak, pine and fir. In September, two hundred last of stone ballast. In November, eighteen-metre pines and beams measuring twenty by thirty centimetres. The dock did not end as a wreck or a museum piece. It ended as lumber - reabsorbed, plank by plank, into the city that had built it forty-six years earlier.