Metropolitan Cammell, the Birmingham-based rolling stock builder, drafted an unconventional design for a sidetipping ballast wagon in 1930. A small batch was subsequently purchased by the GWR (Nos. 100001-100060) and, later, by British Railways. Over 600 wagons were built for BR between 1952-61, and gained the ‘Mermaid’ moniker. The initial batch (BR diagram 1/573), was virtually identical to the GWR wagons and numbered DB989000-989088. The more numerous diagram 1/574 version (DB989089-989638) was upgraded to incorporate vacuum brakes and heavy duty hydraulic buffers. With a gross weight of 14 tons, the ballast load was carried within a steel body that pivoted to either side of the chassis. The shallow side doors were hinged in such a way that the flow of ballast could be regulated. Chain clamps were provided to secure the wagon frames to the rails during tipping and, accordingly, ballast could only be discharged when stationary. The GW and early BR unfitted wagons were largely confined to the Western Region, while the vacuum-fitted fleet was dispersed across all BR regions. Lasting until the early 1990s, they eventually gained a TOPS code of ZJV. With plenty of livery choices (GW/ BR black, Indian Red, olive green and ‘Dutch’ grey/yellow) and long careers, it’s a surprise that we’ve not enjoyed mass-market RTR models of the ‘Mermaid’ in the popular scales. In ‘OO’, Flangeway has produced a limited run model, while this new offering from Djmodels is the first version to appear in ‘N’ gauge. Both BR and GWR versions are available and it’s a pair of the latter that we have received for review, numbered DW100048/50), albeit finished in early BR livery. The simple markings have been applied to a high standard, with overhead line warning icons at each end.
The quality of moulding is universally high, with the distinctive open-framed chassis correctly reproduced. A full array of brake gear is provided, including cross shafts, yokes and safety loops, along with a vacuum cylinder. However, given that the GWR’S ‘Mermaid’ fleet was not vacuum brake-fitted, this excellent detail is only relevant to later BR batches. Presumably, this single chassis option across the range helps to keep the price at a reasonable level. The chassis sports a lovely set of hydraulic buffers (also erroneous for GWR wagons) but, on our samples, a few of these were loose and required re-fixing with a drop of glue. Door tipping equipment has been faithfully captured, with chains and door brackets formed of separate mouldings at each end. A rendition of the track clamps has also been included, while lamp brackets and coupling hooks adorn the bufferbeams. Virtually all key dimensions appear to be scaled correctly, although the wheelbase appears to be a couple of millimetres too long, working out as a scale 13ft instead of 12ft. Removable, realistic ballast loads are supplied and these feature a small metal weight hidden beneath, bringing the wagon’s weight to a respectable 8g. Of note is the ability to remove the ballast load with a magnet. Rapido-style couplings are mounted into NEM pockets, with a set of lower profile alternative couplers supplied. The couplings feature pivoting mounts that permit plenty of sideways, as well as fore and aft, movement. When coupled together, the gap between each ‘Mermaid’ is excessive (8-11mm), although it does allow the wagons to cope with tight radii curves. Under test, the wagons ran freely and reliably. The coupling mounts can easily be knocked out of the frames unless handled carefully. This will lead to derailments, so a quick visual check is recommended before placing the wagons onto the tracks. Aside from the detail issues, especially where the GWR versions are concerned, Djmodels has done a great job in capturing the character of these unusual wagons. The BR ‘Mermaids’ in particular should prove popular with modellers across a wide range of eras and regions.
OF NOTE IS THE ABILITY TO REMOVE THE BALLAST LOAD WITH A MAGNET