Factory Methods of the Vintage Era

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No. 19: Rover

In 1925, when the 14/45 Rover with its complicated valve gear was a brave new model and not the disaster it was subsequently found to be, J. K. Starley was Managing Director of the Rover Company, having been Works Manager from 1903 and successor to Harry Smith in the top position. “The Rover” was in those days at the Meteor works, Coventry, where 1,500 workers were employed. The same number of hands had been employed at Tyseley, Birmingham, making the Rover Eight, where the 9/20 Rover was still made.

The Meteor works had its own iron, bronze and aluminium foundries, and its own forge. It made the radiators and pressed the body and mudguard panels. Only the carburetters, electrical equipment, tyres, wheels and minor body fittings were supplied from outside. Besides the Meteor works there was the St. John’s works in Coventry making the refined 350-c.c. Humber motorcycles, the Fleet works in the same town, devoted to Rover repair work, while bodywork, including Weymann bodies for the 14/45 were built at Parkside, Coventry, where up-to-date wood-working machinery was installed. Here the bodies were trimmed and upholstered but they were painted at the Meteor works, where a battery of steam-heated drying rooms of variable temperature and humidity were available. In London, Rover House at 61 New Bond Street had recently been opened, with fine, lofty and well-lit showrooms, and the London Service Depot was at Seagrave Road, Fulham, only recently closed by order of Lord Stokes.

At the Meteor works the drawing office employed over 60 draughts-men, and here all parts of the car were drawn, also the jigs and tools needed for its manufacture. Moreover, in 1925 it was said to be a daily occurrence for drawings of some obsolete part for an old Rover still in service to be asked for, and supplied. The laboratory tested materials from outside sources, not only the steels and other metals but castings, the limestone used for fluxing the iron and the quality of the coke used in the cupola. Samples of cast metal were analysed every day. The non-ferrous foundry, incidentally, was in Spun Street, Coventry, but the main foundry was in the Meteor works, where cylinder blocks and heads for both 14/45 and 9/20 engines were moulded in special pneumatic moulding machines. The cores were of a mixture of silica sand and sea sand. The cupola capacity was 3½ tons per hour.

Moulding machines also produced all the parts in the malleable foundry, and after the castings had been cleaned they were passed to annealing ovens consisting of two gas-fired caverns of 10 tons capacity each and three coal-fired ovens each of 2½ tons capacity. The ovens had temperature-recording thermo-couples, four each for the larger ovens, one each for the smaller ones, and temperature was maintained at 950 deg. C for 120 hours, before slow cooling took place. Samples were tested after annealing by analysis and hammering.

Aluminium was melted in brick-lined barrel furnaces fed by town gas, which had been installed in 1914. The mixture of gas and air, forming a slight reducing atmosphere, was forced to the four furnaces, and similar furnaces dealt with gun-metal and phosphor-bronze, at slightly higher melting temperatures. The moulds were formed of two large and ten smaller pneumatic machines and a number of hand-operated ones. The large machines rammed a 14/45 crankcase in 11 minutes and two 9/20 crankcases in 14 minutes. A special thermocouple was immersed in the molten alloy to ensure the correct temperature. Rover claimed to have a National expert in charge of their foundry operations.

At the Coventry and Tyseley factories machine tools were still belt-driven by over six miles of belting. There were some 1,000 separate machines, some costing £1,300 each, backed up by automatics, such as 30 Potter & Johnsons running day and night. These machines could machine a flywheel automatically in one hour 15 minutes, and the Churchill face grinders finished both sides of a cylinder head in 20 minutes. A new hydraulic broach dealt with con.-rods, with a half-thou. tolerance at the bushes, and other jobs had a one-thou. tolerance. Gear wheels were ground after hardening, to an accuracy of one-fifth of a thousandth of an inch.

At the Parkside body shop nearly 300 hands worked on 14/45 bodies, Eight and 9/20 bodies being made at Stoke. Seasoned ash was cut in jigs, roof panels were welded into one piece and the aluminium panelling was turned over the window framing to protect the wood. Apart from the Weymann body, all 14/45s had aluminium body panels and were upholstered in the best leather. Five different types were made. Each completed Rover had a lengthy road test. — W. B.