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  • Upgrading the TR4 & SW9 GM Switchers

    Santa Fe's 1235 SSB-1200 EMD Switcher as seen here in China Basin, San Francisco. Photo is by Burr Henion
    Prototype Modeler - February 1978 - Page 8 width=

    by Burr Henion

       This article will illustrate how easily a standard factory kit can be modified to represent a prototype Santa Fe locomotive. I would recommend this kit for any beginner or experienced modeler who would like to tailor their equipment to a real "Santa Fe" look.

       To those who have never attempted a modification of "kit-bash" on a plastic model, it can be interesting, accomplished quickly, and very rewarding. The project outlined below will be organized into several sub-projects or steps, so that each part can be easily finished in a reasonable time.

       The aim of this project will be to convert an Athearn HO SW1500 GM Switcher to conform to the Santa Fe locomotives listed below. The finished model will resemble a 1975 version of the switchers used in the Richmond, California yard today where seven were transferred from the other parts of the system at the end of 1973. Their numbers are: 1222, -23, 32, -35, -37, -39, and 1240. By March 1974, all were in operation replacing the Alco S-2 switchers that were retired due to California air pollution control requirements. They had begun as TR-4, SW-9 or other models originally built from 1939-1953 that were rebuilt several times, the last just before being sent to Richmond with a fresh "Modern" modified war bonnet paint scheme. All look identical with some minor exceptions that will be noted later.

        The project will be broken into segments, as discussed, to facilitate ease of construction and completion; they will be: 1) Disassembly, 2) Trim Shell (long hood and cab), 3) Finishing Long Hood Shells, 4) Finishing Cab Shell, and 5) Chassis Changes.


       If you haven't purchased the locomotive kit yet, I would suggest the Santa Fe (Athearn No. 4005) decorated kit already having the correct medium blue body color. If you prefer to use a Hobbytown chassis, then buy the Santa Fe (Athearn 4055) decorated body shell and a handrail kit.

    The model and the prototype stand side-by-side in this twin-photo. Though it has been around a while this class will probably continue Photo is by Burr Henion to be around for years to come. A real workhorse. Photo is by Burr Henion
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       To begin, carefully disassemble the cab from the rest of the body and remove all handrails. Pull the bell casting and horn, if attached, out of the hole in the top of the hood and carefully remove the clear plastic window pieces from inside the cab. They are snapped in place and the front window should be removed first, then the side windows. The back windows are removed last by gently pushing in on the rear headlight lens with a small wooden dowel or heavy tooth pick. The lens is part of the window piece and acts as a friction-fit "holding dowel."

       Part I is now complete and the disassembly finished. Keep all the parts in a box for re-assembly later and take a deep breath. Forget the project for a couple of days so you won't get too in tense or impatient.


       In the second part, all parts of the shell that do not represent the modern Santa Fe will be removed. Newest safety regulations do not permit the crew to stand on the footboards, and Santa Fe has removed them from these locomotives, so the pilot foot boards at each end of the larger plastic piece should be cut off with a razor saw as close to the vertical plane as possible. Carefully file the balance to achieve a clean, square look at the bottom edge of the pilot. Also, file the handrail stanchion support protrusion flat around the holes at the pilot ends for relocation later.

       On the cab shell, cut two small rectangular holes at the rear of the battery box to simulate the recessed area behind extra grab irons used when climbing up the stairs. This is easy to do. Drill the holes using a size almost as wide as the rectangle, say No. 37, and use a square file to shape the hole to a scale 10" high by 6" wide. Center these holes 27 scale inches from the sides and 12 scale inches from the top of the battery box, rounding the outside edges of these holes to form a smooth opening.

    Timken roller bearing journals are standard equipment on 1235 as this close-up photo clearly indicates. While a small detail, attention to this kind of detail in a model is what makes one a champion. Photo is by Burr Henion

    Using a No. 43 drill, drill all the way through the exhaust stacks for ventilation. A flat spot is filed about one scale foot wide on the right side of the walkway, centered over the middle of the air tank, hanging below. This will hold a flat plate later for the ACI panel.
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       If you want the cab windows open for summer operation, or to place "people" hanging out of same, make the appropriate cuts now. Often, both window panes are slid forward so that both sides have completely open windows; this may be accomplished by cutting out the vertical center window frame and omitting the "glass" when the cab is reassembled. I chose to keep the left window closed and "open" the engineer's right side window about 60%. To do this, the vertical center window frame is cut out along with two-thirds of the right hand and the little frame is glued onto the clear window piece.

       This completes the second part of the project. Now take another break before proceeding as this represents the halfway point.

    A three -quarter view of the body shell after completion illustrates the "Santa Fe " flavor of the model. Extra care is all that is necessary for the average modeler to come up with a really fine model. Photo is by Burr Henion
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       From this point on, the model will take on its distinguishing Santa Fe characteristics. The ACI decal, to be added later, will be positioned on a steel (plastic) plate 24" high by 12" wide and welded (glued) in a vertical position on the edge of the right hand walkway where a smooth spot was filed for it in Part II. Also, a fuel tank filler pipe is added to the rear of each fuel tank at an inclined attitude utilizing scraps from plastic castings about 1/16" in diameter and 3/16" long (actual size). This simulates the scale 4" pipe on the prototype.

       New safety regulations dictate that uncoupling levers must be operated from either side or from above. An extra lever has been rigged with an extension pointing up and a knob on the end to facilitate this. Diagram 9 shows the actual configuration of levers and brackets, though you may wish to simplify it. The upturned levers with knobs is the unique, modern look to capture. Also, add handrails to the front using No. 28 wire. The headlight modification will be covered in Part IV.

       At this point, I might mention that you should use liquid plastic cement for most of the cementing operations described in this project. Rez-n-Bond or Schwartz Chemical Co. are both very fast and strong as they combine both solvent and resin; Testors Liquid Plastic Cement will also do.

    Looking down on the top of the modified shell clearly shows where the changes have been made on the upper face of the model. Note the modified exhaust stacks. Photo is by Burr Henion

    Detail of the coupler release handle for both ends of the switcher. Compare this with section from the cab body, make a fine the drawings when fabricating this component. Photo is by Burr Henion
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       Two marker light brackets are fabricated out of block plastic or ABD angles about 4 scale inches square and cemented to the front top corners of the hood as indicated in Figure 2. The horizontal yellow stripe and "Santa Fe" should be removed from the shell by dissolving the ink with either Solvaset or Decal Set. This can be applied with a cotton swab, such as a "Q-tip," rubbed in until the ink softens, and wiped off. Using No. 26 wire, three handrails should be added to the front radiator as shown, one horizontally about 33 scale inches up from the surface of the walkway, and two vertically about 18 scale inches long, on either side of the radiator.

       On the left side of the hood are three offset ladder rungs located a scale 8'9" back from the front surface of the hood. The bottom rung is 19 scale inches above the walkway and the other rungs are spaced 19 scale inches above each other.

       On top of this hood are two grab irons located above the ladder and next to the top grill as indicated in figure 7; also on this hood top is a piece of pipe protruding 6 scale inches, including its cap. It is 4 scale inches in diameter and about 6 scale inches to the right of the center line. A brass brad or escutcheon pin turned in an electric drill and filed so that the head is flattened and shaped simulates the pipe cap nicely.

       The Athearn bell should be replaced with Details Associates bell No. BE128 and the rope pull lever sticking above the hanger frame should be cut off. Lifting pads, on both sides of the sills, give a crane or hoisting jack a purchase to lift the locomotive body when servicing or replacing the trucks. These lifting pads are shown approximated in the side view diagram and have a modified "T" profile; they are fashioned from 1/8" plastic and are glued at a point just above the truck centers. They are 9" wide by 5n1/2" high, with a 5" wide base.

       A small, rectangular box, 3 x 4 x 3 scale inches should be painted red and shaped from plastic. It is glued under the walkway skirt and lies about 6 scale inches in back of the fuel filler pipe. This represents the Emergency Fuel Cutoff. Since the battery box is a separate section from the cab body, make a fine vertical scratch where the joint should be to keep the cab side from looking too smooth. This completes Part III.

    Bell and hood top detail for the 1200 Class switchers. Photo is by Burr Henion

    Roof top detail of the radio antenna in the rear, the rotating beacon to the right, and the dual horns. The antenna is located in the center of the cab roof with the rotating beacon and horns located forward. Photo is by Burr Henion
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    Prototype Modeler - February 1978 - Page 14 width=


       The cab of this switcher carries many special changes that help identify the locomotive as Santa Fe; the antenna, lights, sunshades, and lettering changes are all added quickly & easily.

        First, add the handrails over the rectangular depressions cut into the back of the battery box. These are a scale l' 3" long, vertical, and centered over the opening. Cement some thin scrap plastic in side the shell behind the openings to close them and complete the job.

       Fill the hole in the boss at the cab front where the horn was inserted with plastic putty, however, do not cut this protrusion off. It will function as a wiring box or air line terminal. The actual horn is a twin unit called Leslie Supertypon and is shown in Figure 10. I could not find a similar unit ready-made, so one was fabricated. It is mounted on the front edge of the roof, 18 scale inches to the right of the roof center line, the largest horn facing forward. (Units No. 1232 and -37 retained the original front horn and mounted the rear facing unit only on the roof.)

        A "coffee-can," or cylinder type, radio antenna is located dead center on the roof. It is 6 scale inches in diameter and about 8 scale inches high, available from Detail Associates as No. RA1801. A round roof vent, about 8-9 scale inches in diameter and 3 scale inches high, is located 15 scale inches from the right edge of the roof and 15 scale inches back from the center line of the roof. This is also available from Detail Associates as No. VT1901.

       On the window pieces of clear plastic, scratch some lines outside on the top two rear panes as well as the side panes of the front window to simulate window wipers; these can be darkened with black ink or paint as in Figures 9 & 12. Then, on the bottom side panes of the rear window piece, scratch four horizontal lines inside Eyelet to represent safety bars and paint these gray.

    The model and prototype, side-by-side, shows the details that can be added for replication. Photo is by Burr Henion
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       The yellow, rotating warning light atop the cab is used at all times, day and night, whenever the locomotive is in use. Unit No. 1240 appeared to have the older "gumball machine" style mounted at the front center of the roof. The others at Richmond have the more modern type depicted in Figure 12. It is a yellow, plastic cylinder, 10 scale inches in diameter and 5 scale inches high, mounted on top of a 12 scale inch diameter base, also 5 scale inches high. These cylinders are mounted on 3 strap iron legs to hold the entire light fixture 4 scale inches above the roof. The location is about 18 scale inches behind the front edge of the roof on the center line. I filed a silver-colored unused eyelet to form the base and legs, with a polished yellow rod of transparent plastic for the top. I drilled a hole in the plastic to insert a small bulb from the bottom and a hole in the roof the size of the rod which was about 18 scale inches long. The rod was then cemented into the roof for maximum strength and a dull black band was painted at its base. The metal ring with legs was then slipped on and cemented to both the rod and roof. A rotary beacon No. RB-106, however, is available from Details West.

    This three-quarter rear view of the model shows the completed body shell. Model and photo by Burr Henion
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       Sun awnings, a traditional touch on Santa Fe switchers, are canvas and held at the top by a metal or wood frame. They hang loosely to a wire bracket at the bottom, allowing them to be folded up if desired. A front awning, 12 scale inches high, stretches 7 scale feet across the right and center windows. Side awnings are 1 by 4 scale feet, while the back two awnings are about a scale 1'3" by 1'10". The outside top corner is cut off because of the roof slope. As a point of interest, the No. 1239 unit did not have the rear awnings when photographed. All awnings were modeled in .010" plastic with No. 28 wire for "U"-shaped brackets, drilled and cemented into the cab walls. These should be carefully attached to make a strong joint as they can easily be knocked off in future handling. Scratch a line through the paint where the top of the awning cements to the cab side and use a thick plastic cement at the bottom to hold the wire bracket to the plastic sheet.

        The inside of the cab is painted light gray, and the line to the air horn is simulated by a piece of No. 28 wire. It is bent into an "L" long enough to fit from the round "junction box" at the front of the cab, to the right side, up through a hole in the roof, and then into the horn. The end sticking out of the roof will act as a stabilizing pin to hold the horn in place.

       Unfortunately, the headlights cast by Athearn are the single lens type and all the Santa Fe locomotives sport twin sealed beams in a vertical arrangement. I tried, with varying degrees of success, to modify the existing castings or replace a part of the light fixture with a piece of plastic tubing, filed to shape. The clear plastic lens piece was carefully filed and sanded, creating a thinner wedge shaped design. The sides were tapered by sanding near the front, top, and bottom of the lens so it would slide back into the smaller openings in the smaller headlight shape. Care must be exercised, however, so as not to destroy the polished surface of the face of the lens. The side of the face of the lens must then be carefully notched to create a figure-eight shape, approximating the twin lens look. This is a very delicate operation. A better solution to the headlight conversion is offered with the dual headlight No. LT 1004 from Detail Associates, or the headlight lens cover (twin sealed beam No. HI-117) from Details West.

       This completes Part IV. The next part will complete the modifications to the Athearn SW1500 including handrails, paint, and decals.


       The last part of this kit-bashing article deals with the finishing touches, completing the modification of this diesel locomotive kit.


       If you didn't purchase your Athearn SW1500 body shell already painted and decorated for Santa Fe, mix a dark blue to match ATSF color, then spray or brush paint the entire body. This should be done before attaching handrails or windows. Color shots and swatches for matching purposes can be found in the November 1971 and September 1974 issues of the "Railroad Model Craftsmen" magazine. For touching up sunshades, etc., a Polly-S Blue (PF-30) toned with PF Night Black yields a hue that closely matches the ATSF blue body. After painting everything blue, the following secondary colors are added:

    Light Gray - cab interior

    Dull Aluminum - exhaust stacks, antenna, and yellow warning light base

    Grimy Black cab roof and fuel tanks

    Engine Black air tanks and pipes

       As a final detail, streak the fuel tank filler pipes and the end of the air tanks with gloss to imitate spilled fuel oil.

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       The lettering of this HO scale model was a concern until I discovered that N scale decals are the right size for the Santa Fe name on the hood sides, about 2 1/2' high by 12' long. MicroScale decals, N scale, are used for the side names and numbers on both sides of each headlight, white on black background, as well as the end numbers in blue. HO Micro Scale decals are used for the other decals needed: cab side numbers, GM name plate, "F", FUEL, Fire Extinguisher, etc. Notice that the ACI label goes on the bottom left front side of the cab and the special bracket on the right side. "GEAR RATIO 62-15" goes on the walkway skirts about 2 scale feet behind the "F" on each side on the truck frames as indicated in Figure 16; both are black.


       Handrails are added last so that painting is easier. The bosses or U-shaped stanchion locators are cut off to keep connections less bulky and closer to scale. The handrails running along the side of the hood should be painted before mounting so that only slight retouching will be necessary afterwards. All handrails are mounted as shown in the Athearn kit drawing, with the following exception: the front and rear platform railings have three stanchions rather than two; Figure 16 shows the shape of these railings and the new location for stanchion holes. Bend this wire carefully and slowly or it will break. Since most GM switchers, including Santa Fe, do not attach the small, forward side handrails to the side sills, I also changed them to go directly onto the walkway floor by simply drilling two holes on each side. Before the cut and straightened ends are slipped in to the floor, though, a small length of electric wire insulation, No. 24 or No. 30 about 1 /32" to 1/16" long, is slipped on to the two rearmost stanchions to imitate the prototype mounting collars.

       There are two more handrails on the pilots, 18 scale inches long, 7 inches out, and 18 inches up from the bottom of the pilot.

       After the paint is dry, glue an extra "gland hand" (air brake hose), with ends dabbed silver gray, to the front and rear platforms. Cal Scale and Kade both make plastic sets. These spare, new brake hoses are carried on each switcher and allow the crew to replace defective ones often found during the day's switching operation.


       Depending upon which chassis is used (Varney, Athearn, Hobbytown, etc.), follow the directions for fitting the body shell over it. The Santa Fe units have roller bearings, rather than the older square journal boxes, and these can be simulated by filing as much as possible off the face of the square journal and gluing on a round, timken-type roller bearing journal sliced off another truck, such as a plastic freight car truck from the scrap box.


       Most chassis are equipped with a single bulb for the front headlight, but one should be added for the rear headlight and the yellow, flashing dome light.


       A nice effect that will help with that finishing touch is the addition of rotating axles as found in the prototype. This is easily done with the Athearn kit by cutting off the ends of the truck journal housings with a jeweler's or razor saw, filing flush with the truck frame. Next, trim short lengths of plastic rod small enough to fit into the remaining axle holes and still allowing for a loose fit. Then, trim the axle ends from Athearn's wheel sets for their roller bearing (rotating axle) freight trucks, No. 90398. The axle is blunt so that the bearing insert must be trimmed to protrude just 2mm above the truck from where inserted and bottomed against the end of the metal axle. When it fits, clean the axle end and place a small drop of epoxy of ACC glue on it. Making sure the axle is centered or it will adhere to the truck frame, insert the new roller bearing into the hole. By rotating the locomotive wheel the fraction of a turn allowed by gear play, it will be assured the axle will not become glued to the frame. When the glue is dry, the axles should rotate as the model rolls along.

       Also, glue a washer to the truck frame allowing a hole large enough for freedom of movement. The washer should be sufficiently flat, .020" to .040", with an O.D. of no more than 5/31" to give the appropriate look. Perhaps a slice from a plastic or metal tube similar to those used in ball-point pen fillers would be about right. After this is complete, paint the axle/bearing ends a black or grimy color so as to contrast to the silver truck frame and give emphasis to the movement.

    Article Details

    • Original Author Burr Benion
    • Source Prototype Modeler
    • Publication Date February 1978

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