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  • Modeling Santa Fe PS2-CD 4750 Covered Hoppers Part 1

    by Ken Edmier

    Photos by Ken Edmier and Tim Frederick

    Model Railroading - November 2001 - Page 32

    After purchasing 8,400 Pullman Standard 4427 covered hoppers from 1963 to 1971, Santa Fe decided in 1972 to start ordering the newly designed PS-4750 covered hopper. Santa Fe purchased 1,600 PS-4750 covered hoppers in two classes:

    Class      Qty.        Nos.             Built

    GA-180   1,000    312800-313799    12/72-2/73

    GA-191     600     315200-315799    4 & 6/75

    After 1975, Santa Fe only added leased or secondhand PS-4750 cars to its roster, including 100 cars leased from North American Car Co. in 1979 and 29 cars from the TP&W acquisition in 1984. (Please note that these cars are quite different then the GA180 and GA-191 cars.) In addition to hauling grain, these cars are used to haul potash and other commodities and can be seen throughout the country and Mexico.

    The PS-4750 was introduced by Pullman Standard in 1972 and featured 18 evenly spaced ribs and an arched roof with a raised center section for the continuous trough hatches. To say the PS-4750 was a success is a huge understatement. Between 1972 and 1984, over 50,000 PS-4750 cars were built.

    The InterMountain Model

    InterMountain produces an excellent model version of the PS-4750 covered hopper, but the prototype used for InterMountains model is based on a Soo Line car delivered in 1978 with truck mounted brakes. The main differences between the InterMountain cars and the Santa Fe cars include body mounted brake detail with b rake lines, hopper gates, diamond tread roofwalk and coupler end platforms, and the top chord reinforcing angle. While the two classes were built only 18 months apart, they are not identical; brake-end details and discharge gates are different. Most railroad PS-4750 cars were built with body mounted brakes, so the same techniques can be used for many road names besides the Santa Fe on cars built in the early and mid '70s.

    I chose to modify, superdetail, paint, decal and weather two InterMountain cars to properly match GA-180 313597 and GA-191 315449, both painted in Santa Fe Mineral Brown with large white Santa Fe lettering across the sides as they would have appeared in October 1983. Many of these cars have been repainted, but you can still see these cars today in original paint.

    My prototype modeling standards are to match the prototype as closely as possible. Depending upon your modeling standards, you may not choose to make all the modifications and upgrades that I have done. I encourage you to try, as not one of these modifications is very difficult or complex.

    Getting Started

    Prototype photo of ATSF GA-180 313597. Palmer Lake, CO; October 1999.
    Model Railroading - November 2001 - Page 33

    Starting with an undecorated model, trim away the air-tank supports on the brake end and circular lip around the brake-line openings on each end. Then, fill these circu lar openings on each end with green putty, sanding smooth when dry. Before attaching the coupler-box assembly to the body, I chose to modify the coupler-box covers t o include screw-on coupler boxes using Kadee® Delrin insulating screws. Drill and tap a #56 hole through the coupler cover and assemble, then insert screw and tighten. Trim the screw flush, using a razor saw, and then remove screw. Make a saw cut through the coupler-box cover only, about halfway b etween the truck bolster and the screw head. Trim about two threads off the screw, reinsert, and tighten and glue the remaining part to the coupler-box assembly. Then fill the hole above the screw with green putty, sanding smooth when dry (see Photo 1). If you are going to install the Plano coupler end platforms, fill the two outside holes on the top of each coupler-box assembly with green putty and sand smooth when dry.

    Using a #78 drill, drill a hole in each end of the coupler cover for the future placement of coupler lift bars. The coupler-box assemblies can now be attached to the body. If you are planning to use Kadee's self-centering trucks, remove the truck posts on the bolsters at this time.

    Brake Gear & Hopper Details

    The train line air pipe is located on the right side, looking at the brake end. For the GA-180, the train line air pipe runs through the end sheets on both ends. For the GA191, the train air pipe runs through the end sheet on the non-brake end and under the end sheets on the brake end. Drill five holes where the right side meets the hopper bays with a #78 drill, making sure to drill diagonally towards the center of the car and install five eyebolts. Two more eyebolts need to be installed, one on the right side of the brake end coupler-box assembly and one on top of the non-brake end coupler-box assembly using the pre-drilled hole. Use a #72 drill to make the holes in both end sheets (GA-180) or just the non-brake end sheet (GA-191). Bend and install the train line air pipe using .015 brass wire.

    The linkage that links the brake cylinder with the trucks actually runs through the hopper bays under the center sill. The prototype cars have a cutout on the side of the hopper bays to allow the linkage to pass through. Start by drilling a #63 hole just above the intersection of each hopper bay with the center sill. Then, enlarge each of these holes with a #52 drill bit. Using a sharp #11 blade, enlarge each of these holes into a trapezoidal shape opening, 15" wide at the bottom of the center sill down to 12" wide, by approximately 5" high (see Figure 1). (I accidentally enlarged the openings on one car too much and just went back and filled part of the openings with green putty. This actually worked out easier and I was much happier with the final shape of these openings.) The prototypes center sill bottom lip was represented using .010 x .030 strip styrene attached to each side of the center sill, making sure the ends of each strip near the hopper bays have a small taper.

    Model Railroading - November 2001 - Page 34

    From the outer hoppers to the trucks, .015 brass wire and some spare Grandt Line brake levers were used (or use .010 styrene strip, shaped to match). The linkage between t he center hopper and the non-brake end hopper is .015 wire, spaced about 1" above the center sill. I used small pieces of .015 wire as a spacer until the CA dried. The linkage between the center hopper and the brake-end hopper is more complicated as the slack adjuster is located here. The slack adjuster with clevis came from an Eel River Model freight-car detail set with a second clevis from Precision Scale secured with CA. Use .015 wire from each clevis for the linkage to the hoppers. The slack adjuster is installed with the Precision Scale clevis mounted about 24" from the center hopper.

    Form four 21" long brake-rod safety brackets from .015 x .042 brass strip, then bend 90° 3" in on each end. Two brackets are placed between each of the hopper bays on the center sill. Place two brackets 15" away from each side of the center hopper and the third bracket 12" away from the side o f the non-brake end hopper. The fourth bracket goes at the brake-end hopper opening, at the intersection with the center sill. Form one bracket 27" long and bend 90° 6" in on each end. Place this bracket 59" from t he brake-end hopper towards the center hopper. Install the six shaker brackets to each side of the hopper bays (see Figure 2).

    The Youngstown discharge gates included in the InterMountain kit are incorrect for most of the Santa Fe cars. The GA180 cars were delivered with discharge gates from three different manufacturers and were applied as follows: Enterprise (312800313299), Keystone (313300-313699), and Fabko, a subsidiary of Youngstown (313700313799). The GA-191 cars were all delivered with Miner gates. Athearn discharge gates (called outlet covers by Athearn) are a closer match for all but the Fabko gates, and can easily be detailed to more closely match the prototype gates.

    For the Keystone discharge gates (GA-180), start by trimming the mounting pegs off the Athearn discharge gate along with the gate tracks right after the opening socket. Two .060 channels are placed on the each side of the discharge gate. The channel must first be notched slightly to fit around and below the opening socket. Cut the channel so that it is even with the front of the Athearn gate and extend 34" beyond the opening socket and secure to the side of the discharge gate. Place a 3/64" angle at the end of the channels, flush with the channel ends and bottom. I simulated the manually locking mechanism for each gate with two 9" long styrene brackets made from .020 x .060 strip styrene, roughly shaped to match the prototype. Drill a #78 hole in each bracket and place a 51" long piece of .015 brass wire through the holes in the brackets and secure to the top of the channels and against the opening sockets side. I represented the gate track with a small section of Plano Apex roofwalk, two slots wide x 34" long, secured to the inside of the channel (see Photo 2). Attach the discharge gates making sure the center discharge gate tracks face the nonbrake end of the car.

    For the Miner discharge gates (GA-191), start by trimming the mounting pegs off the Athearn discharge gates along with the gate tracks right after the opening socket. Two .060 channels are placed on the each side of the discharge gate. The channel must first be notched to fit almost completely around the opening socket. Cut the chan nel so that it is even with the front of the Athearn gate and extend 11" beyond the opening socket. Secure with the channel placed around the opening socket and with the channel continuous on the bottom side of the gate. I simulated the manual locking mechanism for each gate with two 12" long styrene brackets made from .010 x .040 strip styrene. Drill a #78 hole near the top of each bracket and secure on the side of the channels, flush at the bottom with the hole on top. These brackets are placed 3" from the end of the channels. Then place a 60" long piece of .015 brass wire through the holes on the brackets and secure (see Photos 3 & 4). Attach the discharge gates, again making sure the center discharge gate tracks face the non-brake end of the car.

    If you are modeling a GA-180 car with Enterprise discharge gates, build the dis charge gates just like the Miner discharge g ates except the gate track length is 14" long. After securing to the hopper bottoms, add a .010 x .040 styrene strip mounted at an angle on the car side hopper attached to the top of the channel.

    Install the two bay dividers into the slots on the inside of the body and secure. According to NMRA standards, the recommended weight for the finished car should be 4.75 oz. I do not trust the double-sided tape on the A-Line weights, especially inside a covered hopper, as the roof is not removable and the weights are not mounted to a true flat surface. I secured the A-Line weights with Elmer's® white glue, covering the weight liberally, allowing a few days for the glue to dry.

    Plano Roofwalk

    To me, a covered hopper just does not look right without a see-through roofwalk. Plano produces a perfect round-hole (Morton) roofwalk set for the InterMountain car. The bad news is that it is completely wrong for the Santa Fe cars. Most GA-180 cars were built with diamond tread roofwalks. I say most, as I have found a few GA-180 cars with Apex slotted roofwalks. I believe these are replacement roofwalks for the factory installed diamond tread. The GA-191 cars also came from the factory with diamond tread roofwalks. Since Plano does not make a diamond tread roofwalk for the 4750, two #78s, for a 2-bay ACF car, were used for the roofwalk and coupler platforms with the risers and the crossover frames from #83.

    The #78 roofwalk before and after cutting apart one side and end and placement on car. Also note styrene spacer for even roofwalk spacing from raised hatch area.
    Model Railroading - November 2001 - Page 35

    Start by cutting apart each #78 roofwalk. Figure 3 shows the cutting locations. The only tool that I have found that cuts the roofwalk cleanly is cuticle scissors. Work slowly using the joint lines as your cutting guide, sanding square after cutting. The sides of the panels near the ends will need to be sanded smooth to remove the end walkway panels cleanly (see Photo 6).

    Fill the holes in the roof for the kit-supplied roofwalk with green putty, sanding smooth when dry. Do not fill the holes located next to the roof trough for the hatchcover hinges. The Plano template is correct except for the braces under the walkway extension (left-front corner and right-far corner while looking at the roof from either end). Planos template shows a #3 roof support mounted parallel with the carbody. This is incorrect for these Santa Fe cars as each walkway extension has its two supports mounted perpendicular to the carbody. Also, the wider #1 supports are mounted under where the prototype roofwalks are spliced t ogether. Plano has modeled this option very well, but make sure you first place the A-panels over the template. Relocate the #1 support lines and tic locations to match under the splice points while keeping the roofwalk centered. You may also need to recenter the #2 support lines and tic locations between each of the #1 support lines.

    Place this marked-up template on the roof, aligning straight along the edges, and tape into position. Press a drill pilot hole using the Plano-supplied T-pin on each tic of the paper template. Then, remove the paper template and repeat for the opposite side. W hen completed, drill at each pilot hole with a #78 drill bit. I did not use the brass template at all for crossover frames, so no holes were drilled.

    Install the roof, making sure it is mounted with the locator holes for the hatch hinges on the left when looking at the brake end. On the Santa Fe cars, the roof does not overhang the cars end, but is flush. Trim the roof flush with the car ends, being careful not to remove the body vents. Fill any gaps where the roof meets the car ends with green putty, sanding smooth when dry. You may need to ream some of the riser drill holes clear after sanding. The InterMountain kits come with two different sets of hatch covers. The Santa Fe cars were delivered from the factory with ribbed hatch covers, but many later cars also have a combination of ribbed and smooth covers. I decided to model both cars as delivered with ribbed hatch covers. Install the hatch covers and hinges per the kits instructions (see Photo 5).

    Install the risers from set #83, per the Plano instructions, following the numbers on the template except for the braces under the walkway extension, as previously noted. Use two #3 risers under the walkway extension, parallel with the #1 and #2 risers. The crossover platforms on the Santa Fe cars do not have the center support angles. Instead, diagonal braces were used to support the overhanging part of the crossover platforms. After bending the crossover platforms, trim off the mounting pins and install with CA directly to the roof, making sure to keep the crossover platform centered.

    Using Figure 4 as a guide, start with one side and one A-panel, place into position with the end halfway on the wide riser with the etched side lips on top. I secured the roofwalk panels with Cyanopoxy™. I used a piece of .030 styrene as a spacer between the panel and the raised hatch area while placing and securing in place. This helped ensure that all the panels were evenly spaced from the raised hatch area. Install the next three A -panels in the same manner. Using the Morton roofwalk from set #83 as a guide, t rim the B-panel walkway extension to match. Secure in place over the end two risers, again using the spacer and with the side lips up. Measure, trim and sand the C-panel to fit and secure in place. The crossover platform requires three panels. Start by measuring and trimming the D-panel to match the outline of the center crossover piece. Secure in place, again with the side lips up. Then measure and trim each of the E-panels and secure in place (see Photo 6). Repeat this same procedure for the second side and crossover platform.

    Model Railroading - November 2001 - Page 36

    I used spare Plano risers for the center support angles on the crossover platforms, bent and trimmed to fit.

    GA-180 End Detail and Assembly

    The location of the body-mounted brake detail are different between the two classes. The GA-180 class has the brake air tank mounted on the right side. Starting with the brake air tank, remove the plastic air lines and drill two #78 holes where the old plastic brake lines are attached to the tank. On the tank ends, one end has two vertical pieces representing the tank bolt hold-downs while the prototype tank has only one hold-down per end. Remove these two vertical pieces and reinstall one in the center of the tank end. Make two triangular styrene brackets from .030 x .125 styrene strips using a Northwest Short Line Choppers 60° angle. Then remove just a little bit of the angle tip with a razor blade before securing to the tank. When dry, secure on the right side.

    As can be seen in the prototype pictures, the triple valve and the brake cylinder are mounted on brackets. Make a channel bracket to support the triple valve from .100 styrene channel approximately 6" long and mount on top of the coupler assembly. Make two triangular shaped brackets to support the brake cylinder with .030 x .125 styrene strip, cut at a 45° angle with a 3" straight section on one end. Trim off the brake rod on the Atlas brake cylinder and drill a #72 hole in the back and front of the brake cylinder. Attach the triangular shaped brackets and mount the assembly on the left side, centered between the two vertical uprights for the brake mechanism on the end ladder assembly. After trimming the mounting pin from the InterMountain triple valve, determine the orientation of the triple valve per Figure 5. Drill four #78 holes on the right side, two rows of two. Mount the triple valve, with the four holes facing to the right, on the styrene channel. Using .015 brass wire, run one piece from the back of the brake cylinder to the lower left hole on the triple valve, two pieces from the air tank to the top two holes of the triple valve, and run one piece from the lower right hole on the triple valve to the train air line.

    The Atlas brake beams are too short, but can be used as a guide. Make a new vertical brake beam from .020 x .060 x 7' 6" long strip styrene. Drill two #78 holes, 3" and 48" from the bottom, to attach the brake linkage and brake cylinder. Using .015 brass wire, form a small loop through the second hole on the vertical brake beam and feed it through the hole on the front of the brake cylinder. Secure the vertical brake beam in place by connecting the brake cylinder wire and attach the brake linkage line through the bottom hole, trimming the brass wire as necessary.

    Make a new horizontal brake beam from 1/16" angle x 4' 9" long. The brake beam is mounted high on the prototype and is angled upward from the body to the end ladder assembly, with the top of the angle almost level with the long grabiron. Attach this horizontal brake beam to the body and the vertical brake beam, making sure it will match the end ladder assembly (see Photos 7 & 8).

    The Plano roofwalk packages from set #78 also include the see-through coupler end platforms for the end ladder assem blies. However, the GA-180 class does not have the cutout for the brake chain to pass through the brake ends coupler platform, so use the two coupler end platforms without the cutout. Using green putty, fill the holes for the kits coupler end platforms. Drill two new #76 holes for the Plano platforms and install the Plano coupler end platforms. I substituted .015 brass wire for the kits bottom ladder rungs. Before installing the brake mechanism, trim away the molded plastic chain. Do not install the brake wheel at this time. Secure the long grabiron and then drill a #78 hole in each coupler lift bar bracket.

    The ladder braces have a row of small rivets on the angle part that faces outward. The GA-180 class cars were built without these rivets, so remove the small row of rivets by sanding smooth.

    Prototype GA-180 end shot showing brake detail locations. Note how the brake chain does not go through the c oupler platform. This car features A pex (slotted) roofwalk, which is believed to be a replacement. West of Ft. Morgan, CO; April 2001.
    Model Railroading - November 2001 - Page 37

    Starting with the brake end, attach one left and one right ladder brace by placing the rectangular end of the brace in each locator hole on the end of the body. Make sure the long angle section of the brace is installed on the inside with the angle facing down. Trial fit the brake wheel end ladder assembly, trimming the ladder braces and brake beam for a flush fit. Install the end ladder assembly and secure in place.

    Two angles are mounted from the body to the end ladder assembly on both sides of the vertical brake beam. Split a 5' 3" long piece of .100 styrene channel in half, creating two angles. Attach with both angles facing away from the vertical brake beam. Then, make a small pad using .010 x .060 styrene cut 9" long. Place on top of these two angles, just behind the vertical brake beam toward the body.

    I installed a small piece of chain from the brake mechanism to the vertical brake beam. Make a small U-shaped hook from .015 brass wire and place through the last chain link. Place the U-shaped hook around t he vertical brake beam and attach with CA. Run the chain to the right side of the brake mechanism, trimming as necessary to let the chain hang loosely, and secure in place before installing the brake wheel to the brake mechanism. Then, install the left side diagonal brace. I removed the molded-on bracket for the triple valve and the retainer valve before installing the right side diagonal brace. You can straighten the plastic air line attached to the retainer valve or replace it with a piece of .015 brass wire before securing the retainer valve on the right diagonal brace. The air line runs to the side of the triple valve, front lower left hole. Install one left and one right side ladder, securing the side ladders in place, one at a time, from the top to the bottom. You may have to trim the bottom steps to fit flush to the bottom of the end ladder assembly. These bottom steps are mounted behind the coupler lift bar bracket (left side, looking at the end) or diagonal brace (right side, looking at the end) (see Photo 9).

    Moving to the non-brake end, install the ladder braces, end ladder assembly, ladders and diagonal braces. Next month, well cover the GA-191 as well as painting, decaling and weathering. A prototype photo gallery will also be presented.

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