Photos by Ken Edmier and Tim Frederick
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For the GA-191 class, the brake air tank is mounted on the left side and the triple valve is mounted to a bracket mounted on the right side. Prepare the brake air tank as on the GA-180 and install on the left side. Make a bracket for the triple valve from .015 x .042 brass strip, with the horizontal leg approximately 18" long and the angled leg approximately 18" long. Using needlenose pliers, bend the bracket into a V-shape until the end of the legs are approximately 12" apart. The bracket is mounted just to the right of the coupler pocket, with the angled bracket end on the car sill lip and the horizontal bracket end attached directly to the car end.
The brake cylinder is mounted on a pad that is placed on top of the coupler pocket and supported with two triangular supports from the coupler assembly. Make a pad from .020 x .156 styrene strip, cut 12" long, and mount on the left side of the coupler assembly. Then make the two triangular styrene b rackets from .030 x .125 styrene strips using a NWSL Choppers 45° angle, removing just a little bit of the angle tip with a razor blade before placing under the pad and securing in place. Trim off the brake rod on the Atlas brake cylinder and drill a #72 hole in the back and front of the brake cylinder and secure to the pad, 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 (see Part 1). Drill two rows of two #78 h oles on the front side. Mount the triple valve, with the four holes facing out toward the end of the coupler pocket. 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 one from the lower right hole on the triple valve to the train air line.
Make a new vertical brake beam from .020 x .060 x 6' 6" long strip styrene and drill two #78 holes, 3" and 21" from the bottom to attach the brake linkage and brake cylinder. Form a small loop of .015 brass wire and insert through the second hole on the vertical brake beam and feed the wire 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.
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The brake beam is mounted horizontally on the prototype and runs from the body to the end ladder assembly, with the top of the angle level just above the brake wheel. Make a new horizontal brake beam from 1/16" angle x 4' 6" long. Attach this horizontal brake beam to the body and the vertical brake beam, making sure it will match the end ladder assembly (see Photos 10-12).
Prepare the end ladder assemblies as per the GA-180 car, except the brake-end coupler platform for the GA-191 class does have the cutout for the brake chain to pass through. The horizontal brake beam mounts to a small pad on the brake-end ladder assembly, mounted behind and just above the brake mechanism. Install a .030 x .100 x 12" long strip styrene to represent this pad. The GA-191 class cars were built with the rivets on the ladder braces, so these parts were not modified. Install the ladder braces and end ladder assembly on the brake end.
Two angles are mounted from the brake-cylinder mounting pad toward the end ladder assembly on both sides of the vertical brake beam. Split a 3' 3" long piece of .100 styrene channel in half, creating two angles. Attach with both angles facing away from the vertical brake beam with the top of the angles level, ending just below the end ladder assembly.
A trapezoidal-shaped bracket is mounted on the end ladder assembly for the brake chain to run through. Make two pieces from .015 x .100 strip styrene, cut 15" long and trim one corner of both pieces at a 30 angle. Place a 12" long piece .040 x .040 strip in between each of these trapezoidal pieces on the long side and glue together. When dry, secure to the bottom of the end ladder assembly and to the front of the angles running from the brake cylinder mounting pads. The bottom of the bracket needs to be flush with the bottom of the coupler pocket. I installed a small piece of chain from the brake mechanism to the vertical brake beam. Insert a small .015 brass wire U-shaped hook through the last chain link. Place the U-shaped hook around the vertical brake beam and attach with CA. Run the chain to the right side of the brake mechanism through the trapezoidal bracket and the coupler platform, trimming as necessary to let the chain h ang loosely, and secure with CA. Place a .015 x .100 x 12" long piece on the bottom of the bracket extending to the coupler pocket. 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 towards the body.
Now install the brake wheel on the brake mechanism. Install the diagonal braces and retainer valve with air line, and side ladders on the brake end. Then, install the ladder braces, end ladder assembly, side ladders, and diagonal braces on the non-brake end (see Photos 13-15.)
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Install an eyebolt in each of the coupler lift bar bracket holes vertically after bending the eyebolt just behind the eye. Form each coupler lift bar by bending the end straight, and re-bend with a smaller protrusion to place in the coupler pocket cover hole. The coupler lift bar also has to be re-bent to create more of an offset. Install each coupler lift bar through the eyebolt and in the end of the coupler pocket cover and secure in place. Make sure the coupler lift bar does not stick above the coupler lift pocket (see Photo 16). I chose not to install trainline air hoses since I use the coupler trip pins on the Kadee® couplers. If you are not using the coupler trip pins, install trainline air hoses now. InterMountain includes the trainline air hoses (labeled brake pipe assembly) or, as Jim Six suggests, use a Detail Associates freight-car air hose fit to an Athearn locomotive stanchion, cemented or pinched in place.
Both classes had top cords extending over the middle seven bays. Add a Plastruct 1/16" angle x 21' 3" long to each car side, securing to the top of the ribs. Install the roof grabirons to the roofwalk by trimming off the mounting pins and securing in place. On the two cars I modeled, a tack board is placed at the bottom of the first panel. The tack board can be seen directly below the first two car numbers on each car side and do not appear to have been added to all cars. The tack boards are .015 x .080 styrene strip, 9" long. (Please note that the tack boards are missing from the construction photo as I did not notice these tack boards until I started decaling.)
Start by airbrushing the hopper cars with AccuFlex Primer Gray, thinned about 40% with 70% isopropyl alcohol. After priming, paint the primed cars with thinned Santa Fe Mineral Brown. I mixed two parts Maroon Tuscan Oxide Red and one part light Tuscan Oxide to create my Santa Fe Mineral Brown. After the paint has dried, spray with Testors Glosscote before decaling.
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The PS-4750's have a narrower rib spacing then Santa Fe's previous Pullman Standard covered hoppers. From the prototype photos, it looks like all the lettering was narrowed to fit this new rib spacing, and I am unaware of any decals that properly match. Prototype pictures were used to match the lettering for each car and the decals used are shown in the Decal Table. Many of the decals used are not a perfect match, but the closest available.
Note the following distinct lettering differences between the two classes. The GA180s were delivered from the factory with only one lube plate, but many cars ended up with two lube plates, stacked on top of each other. The GA-191s were delivered with two lube plates. The GA-180s do not have the "Pull Here" lettering on the jacking pads or A, B and C on the hopper bays. Also note that the hopper bay cu. ft. capacity lettering is placed higher on the bays on the GA-180 than the GA-191, and the GA-191 requires the decal to be cut in half before placement to obtain proper spacing. The Pullman-Standard builder information lettering is also different between the cars with the GA-191 lacking the PS-2CD lettering and pyramid. Of interest, both classes have two sets of wheel/coupler/brake information lettering on each end, one mounted on the vertical end and a second set on the end slope, and the reporting marks and number on the sidesill between the hopper bays. You may also need to adjust additional information like the reweigh date or lube plates to reflect your modeling era. When finished, spray the car with Testors Dullcote to protect the decals and prepare the car for weathering.
In looking at the prototype photographs of the two cars, I realized that more than one weathering technique was going to be required. I started by applying a grime wash made of one part Railroad Tie Brown and one part Weathered Black using a variation of Jim Six's Q-tip® weathering technique. I added water to the grime wash and applied it with a small brush to one panel at a time. I then used a dry Q-tip (Jim wets the Q-tip with Champs decal setting solution) to remove the wash. You will need to experiment (preferably on an old car) to find the drying time for the wash so you know when to remove the wash for the effect you are looking for. The streaks of grime were done by drybrushing on the grime and feathering with the Q-tip. Apply very lightly and build up as desired, working in an up-and-down pattern. In some non-lettering areas, the area became too weathered and was lightened by drybrushing on Mineral Red. After finishing both car sides, weather the ends, roof and underside of the car. After the wash dried, I added some small white streaks, drybrushing Aged White and again feathering with t he Q-tip. Then, I airbrushed the hopper bays, underbody, and dusted the rest of the car with the grime wash, thinned about 40% with 70% isopropyl alcohol. When finished, let dry and seal with Testors Dullcote.
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Now its time to finish by installing the trucks and couplers. I prefer Kadee's new self-centering trucks, so I replaced the kits trucks and wheelsets. The wheelsets were removed, painted Rust, and the treads polished using a Dremel tool to simulate the shiny metal treads. Drybrush the wheelsets with a little Weathered Black to give each wheelset a different rust/weathering pattern. The trucks were weathered by drybrushing with a little Rust and grime wash. Before i nstalling the wheelsets, paint the brake shoes on the trucks with Rust and install the trucks per Kadee's instructions.
Whether you choose to add just one detail or complete your model as I did, you are on y our way to becoming a prototype modeler. Try it...I believe you will find it very rewarding. I would like to thank D. Scott Chatfield, Tom Chenoweth, Keel Middleton, V. G. Aylward, and especially Tim Frederick for their help.
These Santa Fe 4750s have been in service for nearly 30 years and can be seen in a variety of paint and lettering schemes. Depending upon your era, you can model these cars in any of the lettering schemes shown on the following pages.