Greenfield Coal Bin, Circa 1920

Discussion in 'Coaling Towers' started by Karl, Oct 7, 2010.

  1. Karl

    Karl 2008 Engineer of the Year Supporter

    I am contemplating building the Frisco at Greenfield, MO. I have drawings in the works for most of the structures, and I have completed the drawing for the coaling facility and the privy. The engine house and depot are on the drawing board. I am in the middle of building the coal facility and the the turntable. The coal bin is complete except for the nbw castings and a final assembly.

    During the early 1920's, Greenfield, Missouri was but just one of the 104 locations where the Frisco placed coal "facilities". A May 1, 1926 Frisco document states that at Greenfield "cars" were used as a coaling facility, i.e., hoppers cars or gons were spotted where coal could be manually transferred to the empty tender. However, a contemporary Northern Division B&B document lists a coal bin at Greenfield. The B&B records are vague about the bin; no date of construction is listed and only minimal dimensional data are given. Specifically the bin was 14’-0 x 30’-0, and its floor was 5’-0 above ground. It was placed 4’-4" from the rail, and it was built from second-hand bridge stringers. The coal bin existed at least through 1933, at which time the Frisco severed the Aurora Branch between South Greenfield and Miller, and the need to maintain a fuel source at Greenfield ceased.

    An 1896 Sanborn map shows a "coal shed" adjacent to the engine house lead; the dimensions on the map do not agree with the B&B record. The Sanborn map depicts a structure that is approximately 15’-0 x 60’-0. One might argue that the 1896 structure was replaced with the smaller structure built with the second-hand bridge material. With regard to the discrepancy with the 1926 document, one could also assume that by 1926, the Frisco had seen the duplication of labor required to transfer manually coal from a freight car to the coal bin and then ultimately to the locomotive tender. Perhaps the use of the bin had been abandoned in lieu loading directly from freight cars into the tender by the 1926 date.

    Regardless of its length of service, the Greenfield coal bin was a singular structure on the Frisco’s Northern Division. As determined from period Northern Division B&B records, typical bridge stringers were 8" x 16" x 14’-0 or 15’-0; it’s apparent why the coal bin was 14’-0 x 30’-0.
    There’s not much else to go on, but it is possible to produce a drawing of the coal bin based on some basic assumptions. The first assumption is that the essence of the structure is a box, which sits atop a trestle. One version of the trestle design would have 2 panels with three piers, which would be comprised of stacked, bridge stringers. Three-ply chords would span the three piers and the coal box would rest atop the chords. The second possible trestle design would use framed bents with 12" x 12" legs and 12" x 12" x 14’-0 caps and sills. These material sizes are also typical for the period. A frame-bent support "bridge" would also require 3 bents.

    The B&B record provides the area of the bin, but it doesn’t provide a height dimension. A four foot high box can be built with three rows of the second-hand stringers. The box as drawn has a volume of 1168 ft3. Coal, in situ, weighs about 84 lbs/ft3, and bank (loose) coal may weigh between 40-60lbs/ft3. Thus, filled to the brim, the box will hold 23-35 tons. Coal has an angle of repose of 35 degrees to 38 degrees, and heaping-full the bin will hold 8 tons to 12 tons more. The eight-wheelers and ten-wheelers that plied the Aurora branch pulled tenders that had a fuel capacity of 6 to 10 tons. So with two locomotives running daily between Greenfield and Aurora, the coal supply would have "turned-over" about every 4-6 days.

    I have drawn the bin with steel rods to keep things nice and tight, and lag screws to hold everything together. Lastly, several configuration of the box may have been possible, e.g., one side open, half a side open, etc. Several possible options are depicted in the drawings.

    The track arrangement at Greenfield was very simple; two, single-end sidings handled the industries in town, i.e., a mill, a grain elevator, the lumber yard, the stock pens, a ramp (for new automobiles), and perhaps the city power plant. The single-stall engine house, gallows turntable, and coal bin were located on the third single-ended siding. All the connections were on the south so the crews couldn’t run around their cars; the place must have been a joy to switch, and drops and kicks must have been SOP.

    Given the track configuration, crews could not spot the car of coal in a location where it could remain until emptied. One could assume that when Greenfield was being switched or access was needed to the engine house, the car of coal was placed out of the way.

    One can envision the routine required to keep the bin full. Perhaps, the last move of the day required the crews to drag a car of coal with them to the coal bin as they put the engine to bed for the night. The duty of moving the coal from the car to the bin may have fallen to the night watchman/hostler, who would keep an eye on the water level in the boiler, and who would also fill the coal bin.

    Attached Files:

    Last edited by a moderator: Oct 7, 2010
  2. JamesP

    JamesP James Pekarek

    Nice model & plans! This is good timing for me; my first coal burner will be placed in service next summer, and my other steamer is slated to be converted to coal at some point in the future. Obviously, I need a place to store and transfer coal to the tenders and a full-blown tipple would be out of place on my shortline. This coal bin fits the bill quite nicely. You may see pictures of a 2.5" scale version one of these days...

    - James
  3. wmrx

    wmrx MP Trainmaster

    Pretty cool stuff, Karl. I'm not much into steam, but I'm always interested in historical information concerning Greenfield and the surrounding area. I hope you decide to continue your building plans for this area.

Share This Page