Athearn's Big Boy Should Be Big Success

While only twenty-five fullscale Big Boys were ever produced, surely the number of smaller-scale models has well exceeded a million. And why not? The Big Boy is the icon of speed and power on America’s railroads during the Age of Steam. The Athearn Big Boy arrives in an HO market that features another new Big Boy release, reviewed by us in November, and so we have received dozens of questions regarding comparisons. MRN does not do shootouts! A review is a given product’s moment alone in the spotlight. We publish everything we can reasonably round up on the chosen sample and bundle it into a review for you. If you want to do a comparison, read both reviews and make a decision based upon your own criteria. If you do this, I’m sure you’ll arrive at the best decision for you.

The First Twenty Big Boys

As we look at those twenty-five Big Boys, all of them ordered and owned by the Union Pacific, we see twenty purchased from the American Locomotive Company (Alco) in 1941. This group was eagerly awaited by UP because they promised to have a major and positive impact in the Wasatch Mountains. Three years later, UP ordered five more it didn’t really want; the railroad by this point desired diesel freighters, having seen their success around the nation. The diesels didn’t expend water, were available almost all the time, and didn’t need turntables. Yes, they were more expensive, but UP didn’t mind. Unfortunately, the War Production Board did, and in 1944 UP took five more Big Boys, another twenty Challengers, and ten more 4-8-4 FEF 3s. These would be the last steamers UP ever bought.

So we might call the first twenty of the Four Thousands to be the Ones UP Wanted. There was remarkably little change from the first to the last of that group, No. 4000 to No. 4019. All of them had their air compressor aftercooler grids mounted under the handrails on each side of the pilot deck, perhaps the easiest spotting point aside from the roadnumber. None of the Last Five had them there; their Wilson aftercoolers were mounted behind the front shield plate. Eventually all of the aftercoolers on the First Twenty would wind up there, too, but that changeover didn’t start until 1951.

Throughout the lives of the Big Boys, some of the sparse exterior plumbing migrated here and there, so if your photo of No. 4006 (our sample and the seventh one built) has some different piping, check the publication date. My research tends to conf irm that Athearn has modeled this locomotive as it would have been from 1946 until the early f ifties’ Aftercooler Migration. Most of the other differences between the f irst and last groups are found either inside or in the choice of certain alloys used as a result of wartime restrictions, and members of the 1944 quintet weighed a few tons more as a result.

The transmitter is for use during pure DC operation. Button 1 rings the bell, 2 blows the whistle, STP brings the loco to a momentum stop, 3 slows the loco down, 4 speeds it up, and 5 changes direction.

Athearn’s Big Boy

This new Big Boy release offers one benefit over the two Big Boys released in the past few years: it is two to three hundred bucks less expensive. If you spent the difference on a string of Athearn’s ice reefers, that would be quite a string. And what is the biggest difference? The boiler and tender shells (along with other parts) are molded in styrene instead of diecast metal. Since what you see in all cases is paint, the only real way to tell the difference is to either weigh the model or feel the coldness of metal.

Of course Athearn knows how to put paint on models with consistent perfection, and this Genesis model meets that criterion. Railroads of the period knew about and used aluminized hightemperature paint at the same time as they employed the reliable oil-andgraphite (O&G) concoction that had worked so well for a century or more. Video and pictorial evidence seems to suggest the locomotives were delivered in O&G and this was maintained at least through World War II, a time when almost all aluminum went into the war effort. Afterwards, some locomotives were treated to the aluminized version. Our model seems to have the aluminized paint on the smokebox and firebox, tending to place it as stated above, at which point the aftercooler was moved down behind the front plate.

Another issue in painting on the Big Boys would be the axle bearing covers. Throughout the war years, these were painted engine black, the same as the rest of the underneath gear. Around the time aluminized paint appeared after the war, UP also started having the bearing caps painted with aluminized paint. Generally, they painted the caps on both the trailing locomotive truck and all fourteen caps on the tender. Our sample has the loco trailing truck caps painted with aluminized paint but not the tender. I’m sure this happened at some point, but I would consider it to be atypical in the overall history of No. 4006. With a quick flash of either flat black or silver paint, you could alter this feature as you saw fit.

The entire locomotive is nicely appointed with details. The Big Boy was a truly modern steamer meaning, in part, it had much of its plumbing hidden under the boiler casing. What remained on the outside was there for a reason, and all of it seems to be modeled. The high pressure steam piping to all four cylinders is modeled very authentically, especially the articulated piping on the front cylinders.

Handrailing and grab irons are metal, giving them strength and more appropriate diameter. Finely detailed valves are located atop the smoke box, while the engineer-controlled smoke def lectors are not portrayed in this version. It was very rare to see them deployed since they were for use in the tunnels and cost the engine some power-robbing backpressure. The engineer would close them going in and open them as soon as the nose poked out of the tunnel. Later Big Boy versions from Athearn are projected to model this feature in some way.

I investigated measurements of various items on the Big Boy, mostly by laying the model on its side atop an accurate HO-scale drawing. Mostly, it matched perfectly, and when it didn’t, it was so close that the difference would not be visually discernable.

The Big Boy enjoyed a vestibule cab against the Wyoming winters and had two doors into the cab. It is said that, from time to time, these doors would sport the chalked words “Gents” and “Ladies” though our model gratefully doesn’t. The right door does work, however, being spring-loaded to the closed position. The connection to the tender features a snap-on drawbar, and there is also a 6-pin plug from the locomotive to a socket on the tender where the DC/DCC/Sound decoder and speakers are located.

The tender is almost worthy of a separate review. It is beautifully detailed with a very believable coal load. The parts breakdown drawing indicates the tender can have a wooden deck with coal (WWII), plain deck with coal (post war), or plain deck with oil bunker (No. 4005 only for a short time in the late forties). Quality lettering proclaims the roadname and very tiny but readable lettering on the rear tells us the capacity is “28 Tons” and “25,000 Gallons,” the former being the coal load while the latter is the water.

When 1.1 million pounds passed your trackside location at sixty miles per hour you never forgot the mixture of exhilaration and fear. The model projects size and power within its smaller 1:87-scale world.