Category:Hornby Dublo two-rail system

1996: Page promoting Hornby-Dublo two-rail [image info]

1963: Hornby-Dublo two-rail track [image info]

As the1950s progressed, it was becoming ever-clearer that one of the things that made it difficult for Dublo to compete with other cheaper systems was its clunky, "indestructable", overengineered three-rail track.

The Dublo three-rail system had, like Marklin's counterpart, been based on metal based made of bent sheet to produce a raised track-bad, with heavy clip-together connectors, and very solid rails. The system was advertised as built to last a lifetime, and its not unreasonable when finding a box of Dublo track that hasn't been touched for fifty years, to clip it together, and expect it to work first time.

However, the system was too expensive for casual or first-time buyers (or for parents who just wanted a basic train set to put under the Christmas tree), and for serious owners who wanted to build large and complex layouts, the cost of the track was a significant factor, and for those users with permanent layouts, the need for idiot-proof snap-together track was less obvious.

With Triang producing simple two-rail track consisting of a simple pair of metal rails held together with plastic sleepers, with a clip on each rail to allow them to clip together, the cost was far lower, and Meccano Ltd. felt that they had to be able to be more price-competitive. the new track was "wobbly compared to the rigid metal-bedded system, but this didn't matter so much it it was going to be nailed to a plywood model railway layout base, and the visual appearance of the cheaper system was more authentic. the cheap plastic-looking sleepers could be presented as representing creosoted wood, and if anyone really found their appearance that offensive, they could always paint the sleepers and/or cover them over with miniature gravel.

There were problems implementing a three-rail system on such cheap track, as a three-rail system needed to be able to deal with a pickup being dragged long the centre conductor, and with three rails, warpage could be problematic. But with a two-rail system, the two rails were always inline no matter how one twisted the track, you only had to get good connections for two rails rather then three, and you only used two-thirds as much metal per track section.

Reception of two-rail

The response of many of Meccano Ltd.'s diehard model railway users to the new system was not one of unmitigated glee. Used to the over-engineered "Rolls-Royce" system, the new system looked a bit cheap and nasty, even if it did look more like real track, and avoided the historical anomaly of model steam locomotives running on track with a central third rail. There were certain sorts of track layout that simply didn't work with two-rail – with three-rail, one could set up a tear-drop shaped loop of track that resulted in a train reaching the end of a straight section of track, traversing the loop and then coming back along the same "straight" in the opposite direction. This didn't work with two-rail DC power, as the loco, putting the loco on the same section of track pointing in the outer direction meant that its power supply polarity was reversed, making it want to run backwards. Two-rail also made some of the electrical connections more difficult, as in certain layouts it was possible to short-circuit the two outside rails - with three-rail this hadn't been a problem, as the two outer rails were shorted by default anyway, and one couldn't accidentally connect the centre rail to either of the outer rails. Two-rail made electrical points more difficult, and sometimes required special insulating additional sections of rail, which then spoiled the dimensions of the track unless one added matching short sections of track to other areas.

The two-rail system was also more prone to dirty track and bad connections – with two-rail, the loco wheels were continually rolling over dust and dirt that settled on the rails, and could end up creating an insulating "skin" on the wheels or rails. With three-rail, a connection failure on either of the two rails didn't matter as long as the other outer rail was making a good connection, and the centre rail, which had a "scraped" rather than "rolled" pickup, was to some extent self-cleaning.