USA Trains 1/29 Scale Big Boy

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  • Опубликовано: 13 дек 2024
  • First off join us at www.gscaletrain... or for info to have your loco converted to PS3 contact me here or visit rayman4449.com/ :)
    This is a short video of my USA Trains Big Boy converted to ProtoSound2 by me and operating under DCS. Getting out of the engine yard and onto the mainline. Also playing with a new soundfile that incorporates a quilling whistle.
    Here's some history about the Uninon Pacifics Big Boy's or the 4000 series.
    Big Boy was the name given to the Union Pacific Railroad's twenty-five 4000 class 4-8-8-4 articulated steam locomotives built between 1941 and 1944 by Alco.
    Background
    The Union Pacific Railroad introduced the Challenger-type (4-6-6-4) locomotives in 1936 on its main line across Wyoming. For most of the distance the maximum grade is 0.82% in either direction, but the climb eastward from Ogden, Utah up the Wasatch grade (Wahsatch, on the railroad) is 1.14%, demanding a locomotive with greater tractive effort and horsepower to eliminate doubleheading and helper operations. In collaboration with the American Locomotive Company, the UP's design team, headed by Otto Jabelmann, re-examined the original Challengers designed by A.H. Fetters. They found that by increasing the firebox to approximately 235 by 96 inches (6.0 × 2.4 m) (about 155 sq ft/14.4 m2), lengthening the boiler, adding four driving wheels and reducing the size of the driving wheels from 69 to 68 in (1.753 to 1.727 m), they could achieve that goal.
    History
    The Big Boys were the only locomotives to have the 4-8-8-4 wheel arrangement, combining two sets of eight driving wheels with a four-wheel leading truck for stability entering curves and a four-wheel trailing truck to support the large firebox.
    The Big Boys were designed to pull a 3,600 short ton (3,300 t) freight train over the long 1.14% grade of the Wasatch Mountains in Utah. Before their arrival, helpers were needed. Adding and removing helpers from a train slowed them down. For such locomotives to be worthwhile, they had to be faster and more powerful than slow mountain luggers like the earlier compound 2-8-8-0s that Union Pacific ("UP") tried after World War I. To avoid locomotive changes, the new class would need to pull long trains at sustained speed-60 miles per hour (100 km/h)-once past the mountain grades. Towards the end of the 4000's career (in the late 1950s) it was found that they could still pull more than their rated tonnage of 3,600 tons (3,300 t). Their ratings were increased several times until they regularly pulled 4,450 short tons (4,040 t) up the Wasatch grade, unassisted.
    They are articulated, per the Mallet locomotive design, but used simple (single) rather than double expansion, unlike the original Mallet design.
    They were designed for stability at 60 miles per hour (100 km/h). They were built with a heavy margin of reliability and safety, as they normally operated well below that speed in freight service. Peak horsepower was reached at about 35 mph (56 km/h); optimal tractive effort, at about 10 mph (16 km/h).
    25 Big Boys were built, in two groups of ten and one of five. All were coal burning, with large grates to burn low quality Wyoming coal from mines owned by the railroad. One locomotive, #4005, was experimentally converted to oil. Unlike experience with the Challenger types, this was not successful, and the locomotive was soon changed back to coal. The cited reason for this failure was the use of a single burner, which, with the Big Boy's large firebox, created unsatisfactory and uneven heating. It is unknown why multiple burners were not employed, though with dieselization in full swing after 1945 the company probably lost interest in further development of steam.
    Postwar increases in the price of both coal and labor and the efficiency of diesel-electric motive power foretold a limited life for the Big Boys, but they were among the last steam locomotives taken out of service. The last revenue train hauled by a Big Boy ended its run early in the morning on July 21, 1959. Most were stored operational until 1961, and four remained in operational condition at Green River, Wyoming until 1962. Their duties were assumed by diesels and turbines.

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