In 1946 a small company called Rovex Plastics Ltd. was formed in Chelsea, London producing plastic model cars and other items for the department store of Marks and Spencer. Towards the end of 1950 they had encountered problems with the name on the boxes (ROVEX) as the large British car manufacturer of Rover Cars objected to it. Following this they turned their attention to producing a train set for Christmas, using the plastic injection moulding processes with which they produced the cars.

They produced a Princess Royal locomotive, based on the ex-LMS Pacific and two short coaches with track and a 12v accumulator (battery) but production problems saw them searching for somebody to invest in their trains. Meanwhile Lines Bros., a large toy company selling dolls, prams etc., saw the potential of plastic model trains and decided to buy the company and re-named it Rovex Scale Models. The parent company was known as 'Tri-ang' reputedly named after the three Lines brothers (Tri) and by December 1951, in an effort to expand the range of model railway items, they had also brought in the products of another small company called Pyramid Toys. This company was selling an 00 gauge clockwork tank  locomotive  and several wagons under the Trackmaster banner, but  had been badly affected by the Korean War and the associated shortage of raw material.

By 1952 the new company had been launched selling probably the first UK 2-rail system called  'Tri-ang Railways' and known as Rovex Scale Models Ltd.

Although they sold the original Trackmaster 0-6-2 tank in their own boxes, the first true Tri-ang locomotive was the 0-6-0 tank engine or 'Jinty' that was to form the basis for a number of model variations over the next 20 years.

By the clever use of a mixture of British prototypes and continental style models the Tri-ang range captured the imagination of innumerable small boys whose pocket money didn't stretch to the more expensive Trix Trains or Hornby Dublo. Once hooked on the 2-rail system most people stuck with it and expanded their system with the vast range, which Tri-ang produced.

Eventually Tri-ang Railways saw off most of the opposition of the time, Playcraft, Trix Trains and Hornby Dublo, whom they bought out in 1965.

Tri-ang Railways prospered not only in the UK but also in Canada, Australia, New Zealand and South Africa where models were both manufactured and assembled from components sent out from the UK.

However by the late 1960's even the parent company Lines Bros. were suffering from the effects of a diverse and widely distributed company and a loss of interest in model railways generally. Although they eventually folded, they were bought out by Dunbee-Combex-Marx and a result of this the Tri-ang name was lost but the products and style pioneered by those original designers and managers from Rovex Scale Models days continued.

Today the name Tri-ang has gone, Margate no longer produces trains but the legend still lives on under the Hornby Hobbies banner.