This model is a heavily modified Emerald Night. Being down-sized by four studs garnishes this Atlantic type locomotive with a slightly improved appearance through bends and switches.
About this creation
Bucking the trend somewhat, with this model I have down-sized rather than up for one specific reason: the less than desirable body swing exhibited by all large non-articulated steam engines of the LEGO variety. Secondary motivations include the ongoing suspicion of an impending derailment, which really took the fun out of the Emerald Night. I wanted to create an engine that could negotiate a bend with style and had a leading truck that was not interested in taking flight at crucial moments. With this Atlantic type I have achieved a very good approximation of what I had originally intended. The leading truck is able to traverse both laterally and horizontally, and with the weight of the forward section of boiler, frame and cylinder housings relying on its support, the leading truck, and indeed the entire forward section, hugs the rails beneath with a renewed enthusiasm. In fact, I am so pleased with this function alone that I am considering scrapping my entire fleet of Pacific's, and commissioning my workshops to begin construction of a further two Atlantic's.
I also wanted to create an engine that could convincingly represent a US steam engine with an acceptable level of aesthetic satisfaction. While I was not aiming for perfect accuracy or faithful adherence to any particular class of Atlantic, I wanted to achieve a result that was immediately recognizable as a US built steam engine.
This brings me onto the topic of cylinder housings and piston rods. From my observations, every design that I have seen that incorporates a rod-thru cylinder function looses something important from realism, and the Emerald Night was no exception to this. While the Emerald is a fine looking machine and displays exceptional design talent, the cylinders and such seemed like a first attempt that was settled for rather than refined. Given that a rod-thru design really does limit the scope of what is achievable as far as realism of appearance is concerned, I eventually conceived of a design that gave the illusion of a functioning rod and cylinder. A few strategically placed light grey plates have provided a backdrop for the moving parts that creates the illusion of connection at first glance. Without needing to provide access for a thru rod I was able to create a cylinder housing that pleased the eye and added to the overall appearance of the running gear.
To build this model you will need an Emerald Night and the corresponding instruction booklet. The greater part of the model closely follows the original plan. I have effectively removed the section incorporating the four stud width of the forward driving wheel pair. Remove all the dark green elements and replace them with black and various brown elements. This means you will need 12 additional black boiler casing elements. I found these difficult to source locally, so I acquired the parts by purchasing 3 Western Train Chase kits.
Because the design from the dome to the rear of the cab is essentially the same as the Emerald it is still possible to incorporate the power functions components and power things up for some express passenger traffic.
The main alterations to the Emerald design are found in the leading truck and cylinder construction, and the front of the boiler and smoke box. I have also added a single plate row to the cab just below the windows and to the top of the firebox.
In addition to the 3 Western Train kits, you will also need a black and light grey 4x4 round plate, a single 2x2 convex lens, 2 light grey 2x2 round tiles and being able to source parts from a power miners kit or two will be very useful when you start to add detail and dress the model up.
With all the spare parts you have from purchasing three Western Train kits you can also create the caboose pictured. This caboose is twenty-two studs in length and features twin-axle pivoting trucks. The design loosely follows the Bobber Caboose from the Western kit.
The Atlantic type was largely consigned to express passenger runs and was well suited to the role. The Atlantic's were superseded by the more capable Pacific's, but ironically, Atlantic type locomotives were amongst the last engines from the age of steam to still be in active service. The last of them were retired in the early 21st Century. Due to low adhesion and inevitable drive wheel slip, the Atlantic type saw little in the way of freight haulage, though some railroads found use for them on short-haul light freight duties. However, in a Lego world, these babies can haul whatever consist you choose.
The running gear operates smoothly and flawlessly. This is primarily due to the twin thru-axle arrangement of the drive wheels and offsetting the opposite connecting rods (of course). The leading truck has the micro wheel for look, and to permit the cylinder's close proximity to the under-carriage frame. This construction is also a major divergence from the Emerald design and is quite simple to achieve. The forward drive wheel pair is un-flanged and is the only option if you intend to power the model. Regardless of this, one pair of drive wheels must be un-flanged to negotiate a fixed curve or switch.
Quoting El Barto !
Sweet! Is this going to get integrated into the town? Whistle Stop tour? A Lego Theodore Roosevelt, perhaps?
Yes it is going to be integrated. The layout will be a two-level config with the town aspect overlapping around 50% of the lower level rail network. Over the following months I will be looking at designing structures to hide the set-down and imagine that this will incorporate buildings, staircases, tunnel openings and various other obscuring devices that ought to make the set-down the focal point of the entire display.