Mariana Mesa – USA On30

Club member and secretary Steve Benjamin is the builder and owner of Mariana Mesa, an On30 USA layout. Here is Steve’s description of the layout.


“The name : Mariana Mesa  – Marian is my wife and a mesa is the name of large flat topped plateaux in the high deserts of North America, particularly the Rockies and Arizona.  So merging those 2 together we get Mariana Mesa.  Naming it after my wife has gained me millions of Brownie Points.

A locomotive heads over the bridge taking it over the dried up river.

The origins : I’m interested in narrow gauge railways and railroads.  Anything from the little Lincolnshire Potato Railways and Welsh slate mines to American logging railroads and the big railroad systems that served large areas of the Rockies.  Many of these railroads produced specialised locomotives and rolling stock and on this layout we have both ‘normal’ rod-driven locos and gear-driven specialities.  There were 3 main designs of geared locos – Shay, Heisler & Climax, although other less well known designs were also built.  All were designed to traverse very roughly laid track and pull very heavy loads (logs, mine ore etc).  Some examples still survive throughout the world.  The strange coverings on the smoke stacks are different types of spark arresters to prevent setting fire to the tracksides and forests.

The story : The layout is based in the high Rockies and represents a small town that has grown up with the growth in silver mining and logging.  For timescales, it probably around the 1930/40s.  Railroads, automobiles and horse-drawn transport co-exist.  Being high desert, winters are cold and summers are hot.  Vegetation is sparse and the summer sun bleaches the colour out of most things.

The technical side : It’s an On30 layout, O scale (7mm/ft) but using OO/HO gauge (16.5mm track) to produce a narrow gauge track width.  This approximates to 2’6″ (30 inches), hence On30. 

Full view of Mariana Mesa.


The track is DCC controlled using a SPROG 3 driven from a Raspberry Pi single board computer.  The Pi runs JMRI (Java Model Railroad Interface) and the locos are linked by the Engine driver App and use Mobile Phones as controllers.  The SPROG costs about £60, The Pi is about £35, most Android mobile phones can download the App for free, a similar App exists for Apple.
The switches (points in UK parlance) are operated from the mimic panel using MERG controls.
The turntable uses a stepper motor and a MERG control board.  This board can be taught where the connecting tracks are around the turntable, although the turntable is occasionally slipping on the main shaft and has to be realigned every so often (This will be fixed in due course).
The layout has 3 fiddle yard connection points, it is shown today as an L shape but it can have a yard at either end increasing the ability to offer more varied traffic.
The yard incorporate connections to all 3 scenic layout connection, a sector plate and a turntable to maximise its capability.”

For more information on booking this layout for shows, please Contact Us.

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