HELJAN CLASS B TANK WAGON

Tank wagon design changed very little during the first half of the 20th century. However, in 1957, wagon builder Charles Roberts worked with the British Transport Commission to produce a four-wheel tank vehicle with a longer wheelbase and an increased payload. With vacuumoperated clasp brakes, pneumatic buffers and roller bearings, the new wagons could run at faster speeds. Two sizes of welded steel barrel were on offer, each mounted on four saddle brackets. Both variants boasted a 22-ton payload capacity and a gross weight of 35 tons but the barrels of the Class A tanks were slightly larger to accommodate lighter, oil-based liquids. A shorter tank was provided for denser Class B products, such as kerosene/ paraffin, gas oil, light and heavy fuel oil. Esso took to the new design instantly and commissioned a large fleet of Class A and B tanks in 1958. Other oil companies followed and a number of wagon builders turned out ostensibly similar designs. The wagons enjoyed successful careers, although the design would be superseded in the early 1960s by the arrival of the slightly larger TTA four-wheel tanks. The last Class Bs were phased out in the early 1980s, with the demise of vacuum-braked freight working. A good number of Class A and B tanks subsequently carried on in industrial and departmental use into the 1990s.

THE MODEL

Modellers in 4mm scale previously had to rely on a plastic kit, albeit an excellent one, that dated back to the 1960s (ex-airfix, now produced by Dapol). Now, Heljan has followed up its recent 7mm scale model with a ‘OO’ version - Class A and B variants are due for release in a variety of liveries. Unusually, the first model to appear is a special anniversary edition celebrating 60 years of Heljan. With the tank barrel decked out in Heljan’s blue and red house colours, the limited run of 200 wagons makes for a colourful collectors’ item. Look closely at the printed wagon plates on the solebars and they announce that the wagon is the product of Heljan AS, Søndersø, Denmark! The vivid scheme will not be everyone’s cup of tea, but due imminently is a variety of authentic livery options for operators such as Esso, Regent and Charrington, as well as unbranded departmental versions for the 1980s era, samples of which were on display at Warley 2016. However, the limited edition version does at least allow us a first chance to examine a production model in detail. Colour aside, the first impression when removing the model from the box is favourable with the character of the real thing captured effectively.

FINE FOUNDATIONS

All of the key dimensions are spot-on and the chassis includes a welcome array of vacuum brake equipment. Twin cylinders, actuating arms, rodding, clasp shoes, yokes and safety loops are all present and correct, as is the bottom discharge plumbing. The frame pattern has been faithfully reproduced and is visible beneath the tank barrel. Discreet metal blocks are inserted into the plastic frames behind the headstocks. There’s plenty of mass to ensure reliable running, with it weighing in at a respectable 43g. Pivoting NEM coupler pockets are installed, with a pair of narrow tension lock couplings supplied in a separate plastic bag. Fine-profile, three-hole disc wheels turn freely in the frames, with the brake shoes perfectly lining up with the treads (‘EM/P4’ modellers will have some work to do!). The separate brake handles are correctly profiled and add a touch of finesse to the frames. Moulded relief, in terms of the spring and roller bearing axleboxes and the array of rivet and bolt heads is impressive. Lamp irons, vacuum pipes and sprung buffers complete the list of chassis fittings.

SEAMS SO

As for the tank barrel, recessed panel seams have been rendered but these are a little heavy-handed - especially at the ends. Etched walkway panels are a pleasing touch, although the mounting brackets and frames are inevitably a little chunky to withstand handling. The tank filler hatch correctly features a set of Holdfast bolts and the handwheels and hatch rest are also in place. The plastic ladders are slightly but not excessively - oversized but Heljan has not forgotten to add the small pipe loop at one end of the barrel. Apart from the heavy seam lines and over-scale fittings, this is an attractive and useful model that should prove popular in the more authentic livery schemes. Most commonly employed on block train workings, there’s ample excuse for an investment in multiple wagons!