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  • Rock Island Center-flow Hopper

    "A" end of Rock Island No. 13978 photographed in November of 1977. Note the position of the tack board and the adjacent roping staple. - Photo by Tom Cobb

    Close-up of the "B" end of Rock island Center Flow Hopper No. 13978. Note that this car is equipped with 36" wheels. - Photo by Tom Cobb
    Prototype Modeler - February 1980 - Page 38 width= Prototype Modeler - February 1980 - Page 39 width=

    by Tom Cobb

       Near Union Station in downtown Houston, there is a dry bulk unloading facility where often one may find a collection of center flow hoppers under varied ownership spotted for unloading. In November of 1977, while attending an open house of a local model railroad club at Union Station, I happened to notice a Rock Island four-compartment center flow hopper spotted on one of the tracks leading to the dry bulk facility. Upon close inspection, I discovered that Rock Island 13978 bore a striking resemblance to Athearn's four-compartment centerflow model. Photos confirm this similarity; it appeared that with only slight modifications a presentable model of the Rock Island prototype could be added to my roster.

    This is the left hand side of the Rock Island four-compartment Center Flow Hopper built by American Car and Foundry in May of 1967. - Photo by Tom Cobb
    Prototype Modeler - February 1980 - Page 40 width=

       Typically, a freight car model discussed in these pages will be representative of a large number of cars in actual prototype service at one time or another. In the case of this Rock Island ACF center flow, it is based on series 13978-13986, a total of only nine cars with a 5250 cubic foot capacity built in 1967; all cars were still in service nine years later in October of 1978.

       I have to admit to a certain bias in regard to the Rock. Its freight equipment is especially fascinating with many changes that have occurred in lettering styles and paint treatments over recent years.

       In regard to the center flow hopper, the American Car & Foundry (ACF) pear-shaped design has become a standard in the industry, a truly contemporary railroad workhorse. From my observations, it appears that there are considerably more center flow hoppers equipped with three compartments than with four. This series represents the only center flow hoppers owned by Rock Island that have eight round hatches and four discharge outlets like the Athearn model. Rock Island series 13988-13997 also represents a 5250 cu. ft. car, but it is equipped with six round hatches rather than eight.

       Athearn does not have available a center flow model lettered for the Rock Island; for this reason I selected their Union Carbide kit No. 1921 since it was painted light grey.


       Prior to assembly, I began the minor modification work by removing all stenciling and heralds with a Q-Tip dipped in a decal setting solution. With a single-edge razor blade, the side steps and the brake pipes molded on eash side sill were removed; be careful not to nick the side sills or damage the triangular brake pipe hangers. Using an emery board, the base of the side sills were smoothed where the brake pipe moldings had been removed. According to photographs of Rock Island 13978, the tack boards needed to be relocated. Again using a small emery board, I sanded the tack boards flush with the side sills.

       The next step involved adding additional weight to the car to meet my particular requirements and assembling the car body components. Assembling the model, except for the trucks and couplers, before adding the side sill details appears to be the most judicious move.

       New sill steps were formed from flat wire following the outline of the original plastic steps. Using .020" wire, new brake pipes were attached to the back of the pipe hangers with cyanoacrylate adhesive. The length of wire necessary for this operation can be determined by measuring the length of the cast on brake pipe before removal. Small tack boards were cut from .020" x 3/32" wood stock and placed at the correct location indicated in the photographs. The final step in detailing the side sills required the drilling of a hole in each of the four roping staples found near the end of each side sill.

    Athearn's HO model of the ACF four-compartment Center Flow Hopper as revised. Note the brake pipe running parallel to the side sill. - Model and photo by Tom Cobb
    Prototype Modeler - February 1980 - Page 41 width=

       Upon comparing a paint chip from a grey painted ACF center flow hopper against the grey-green Athearn paint, I decided to try and mix a closer matching color. At the conclusion of some experimentation, I came up with an equal mixture of Floquil's SP lettering grey and reefer white which approximates the ACF grey although it is not an exact color match. After applying this mixture I was satisfied that it looked "right."

       For this model I selected the Frederick Manufacturing roller bearing trucks with the rotating bearing caps. Truck frames were painted black. Couplers were given a coat of Floquil's rust.

       The decals used came from Micro Scale's Rock Island freight car sheet RH-19, gothic style freight car data sheet RH-2, and their center flow hopper sheet RH-24. The 30" block letters on the car sides are from the RH-19 sheet. All of the data appearing on the center flow's side sills, such as the "four compartment" notice, came from the RH-24 sheet. Close examination of the photos of the prototype will show that it was stenciled "Home for Repairs." Probably one would not choose to apply this particular information. Adjacent to the reporting marks the car is stenciled: "When empty return to CRI&P Ry, Marseilles, Ill."

    Article Details

    • Original Author Tom Cobb
    • Source Prototype Modeler
    • Publication Date February 1980

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