NZR WF Class - The Tasmanian Government Railways DS Class

The Tasmanian Government Railways DS Class

Immediately following the Great Depression in 1936, the Tasmanian Government Railways found itself unable to manage the increased tonnages it was being made to handle. Many older locomotives which had been withdrawn and were due to be scrapped were returned to service but a shortage of locomotives remained. The Chief Mechanical Engineer, H. J. Bennett, wrote to the CME of the New Zealand Government Railways, P. R. Angus, requesting a book of engineering drawings of NZR locomotives, and also asking if the NZR had any locomotives it could sell to TGR, enquiring in particular to the WW class 4-6-4T tank locomotives.

Angus advised Bennett that the NZR could not spare any WW class locomotives as they were indispensable to NZR. He instead offered the WF class 2-6-4T as a suitable design that could be released due to the conversion of locomotives of classes BB (4-8-0) and C (2-6-2) to heavy shunting locomotives. The WF class was by now largely confined to shunting work, except for those allocated to the isolated Picton and Nelson sections.

TGR agreed to purchase a batch of four WF class locomotives in 1939. Accordingly, Angus wrote to the District Mechanical Engineers in Wellington and Christchurch, before asking James Binstead, the DME for the South Island, to select four WF class locomotives for sale. Locomotives WF's 381, 385, 436 and 437 were withdrawn and transferred to Hillside Workshops for overhaul and rebuilding to TGR specifications.

TGR purchased a further four locomotives in 1944 due to wartime requirements on traffic. This time four North Island locomotives were selected, WF's 392, 405, 431 and 434. These locomotives were equipped with new welded boilers making them marginally more expensive than the 1939 batch, which had retained their original saturated boilers. The four locomotives were rebuilt at Hutt Workshops before being shipped to Tasmania.

The eight locomotives became the TGR DS class on arrival and entry into service, receiving road numbers DS 1-8. They were used on suburban service in and around Hobart and also for shunting and short-haul freight work. However, the locomotives were not particularly successful as the TGR used soft coal, on which the WF class were known to be reluctant steamers. Certain engines also suffered from reliability concerns, which later led to trial modifications made to DS 7 (WF 434) by shortening the smokebox by 520mm and fitting a narrower 'Master Mechanics' funnel. This modification was successful, but despite the order to equip more engines with this modification, DS 7 remained the sole engine with this alteration.

The first four locomotives were identifiable from the later four by several distinguishing features:

• The first four locomotives had brass 'acorns' on their smokebox doors, while the later four did not.
• The first batch of four locomotives had small shunting-style headlights. The second batch had larger mainline headlights, which were later replaced with the shunting-style headlights later in their working lives.
• The sanding gear on the first batch of locomotives was hand-operated. On the second batch, the sanding gear was operated by a vacuum ejector.

The locomotives were all fitted with three-link screw couplings, vacuum brakes in place of Westinghouse air brakes, Detroit sight-feed lubricators, and electric marker lights on the smokebox side and bunker to make them suitable for TGR service. With the arrival of the new DP railmotors and the V class 0-6-0DM diesel shunters (mechanically similar to the DS class), these locomotives were progressively withdrawn from 1951 when DS 2 was withdrawn. The last, DS 7, was withdrawn from TGR service in 1958.

DS 1 and DS 4 were sold in 1951 and 1952 respectively to the Mount Lyell Railway & Mining Company, who operated them until 1953. The locomotives were used mostly between Regatta Point-Dubbil Barril and Rinadeena-Queenstown, and had their cowcatchers removed to facilitate transfer over the rack section of the line. DS 1 was first to be withdrawn in 1953, and was used as spare parts for Regatta Point-based DS 4, which was withdrawn later that year. These locomotives were fired on a mix of 60% Tasmanian soft coal and 40% NSW hard coal, which delivered a better result in steaming.

During 1953, the Emu Bay Railway required a shunting locomotive to work in their Burnie yard. TGR appropriately reactivated DS 5, which was sent to Burnie and worked there for several months. It was later returned to TGR, and was finally written off and scrapped in 1956 at the Launceston Railway Workshops.

Today, the last remnant of the DS class (other than the NZR builder's plate) is the superheated boiler from DS 8 (WF 392), owned by the Van Diemen's Light Railway Society and stored at their Don River Railway. It was used after withdrawal to provide steam for the caustic baths at Launceston Workshops.