I considering modelling the time from 1910 to 1930, and wondered how long a freight train was. Apart from coal, were there a lot of unit trains? The region would be the upper Midwest.
Jacob,
Until about 1960 or so, there was no such thing as a “unit train”, by Federal law. True, there were regularly trains of all one sort of car heading in the same direction, but they had to be treated as individual carlots. A Upper Peninsula string of ore cars wouldn’t be called a unit train until well past the steam era, and it wouldn’t be surprising to see a boxcar or two tacked in.
As for train length, it really depended on tonnage ratings of the line in question and the steamers that ran on it. In general, you’re interested in the pre-superpower era, but that doesn’t mean that all engines were small and wimpy. I once heard a Pennsy oldtimer talking about getting freights out of Altoon and over Horseshoe Curve in the 1940s: “We’d assemble a 100-car train in the yard, and just start hanging I1’s (PRR 2-10-0) on the train until it moved.” Before superpower and the idea that you could run short trains at high speed more economically than long, slow freights, most railroads subscribed to the “drag freight” theory. Basically, figure out how much a mile-long freight would weigh, and buy an engine appropriate to drag it across a division. That’s why so many roads had 2-10-2s. If freights weren’t mile-long slow movers, they were usually short (10-30 cars) locals, pulled by the smaller engines of the day: 4-4-0s, 4-6-0s, and 2-6-0s. Moreso than 2-8-0s and 2-8-2s (which were still frontline mainline steam power) these itty bitty engines were the GP7’s of the time, and poorly represented in the modelling world.
As for “real” data, I suggest you head on over to your local library and dig up general histories on the Soo Line and C&NW. Both lines are VERY typical of the region you’re interested in, and early histories and photo sources will give you an insight into how the roads operated.
Another source you might try is Locomotive Quarterly. It’s not cheap, about $10 an issue but it’s full of beautifully reproduced, all steam, and mostly WWII and pre-WWII with many pre-WWI. Metaphor, PO Box 383, Mt. Vernon, NY 10552. $$47 per year or $12.75 per back-issue. Drop them a line and ask for a list of availabel back-issues.
Railroads operated soild grain, ore, coal , and reefer trains. They weren’t "unit’ trains though. 1910-1930 is when railroads started getting BIG engines. This was the era of the drag freight. Freight trains would be powered by 2-8-2’s, 2-10-2’s, and 2-10-0’s passenger trains by 4-8-2’s, 4-6-2’s, 4-6-4’s. Locals would be 4-6-0’s and 2-8-0’s. In the mountains you would have 2-6-6-2’s, 2-8-8-2’s, 2-10-0’s Most of your cars would be in the 36-46 ft range, maybe a few 50’ boxcars of 50-52’ gons. Ice reefers. Lots of doublesheathed and composite boxcars and gons. Hoppers would be mostly twin and quad and all steel. Most boxcars would be under 10’ IH and 30-40 ton cap. 100 ton cars would be very rare.
Dave H.
My understanding of a “unit train” is where the string of cars remains coupled for loading and unloading and its movement between its end point terminals. Previously the cars of a coal tran were loaded as individual cars or short strings and often taken to a yard to be assembled into the “train”. Even the iron road trains were split for unloading. The “reefer” trains were assembled from rakes from packing houses and then distributed to the unloading tracks at the destination.
A unit train is a train that is for one consignee or from on shipper where the cars are all on one waybill. Pre-unit trains might have all one commodity, but the cars were all individually billed.
Dave H.
Actually the unit train concept got its first try-out during WWII when German U-boats threated our tanker fleet and the railroads were asked to move the oil between the
Gulf states and the Northeast. They assembled solid trains of oil cars and ran them in blocks without intermediate classification from shipper to receiver and back again.
It wasn’t called a “unit train” though but publicized as a " pipeline on wheels".