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Illinois Live Steamers!
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Turnout Construction By Carl Baskin
Introduction: Perhaps the title would be better served if it read instead…”Turnout Assembly”. This article describes how the ILS (Illinois Live Steamers) “assemble” a turnout on a table jig and not how to “design” the turnout. Two “well coordinated” members, can assemble a complete 7.5” gauge, #8.5 turnout in as little as 2 hours. ASSEMBLY time does NOT include the several hours of PREPARATION time needed to cut ties and machine the various parts, points and frog castings. Don’t let that scare you from building turnouts. Sooner or later, you’re going to want some switching choices on your own railroad. For efficiency sake, once machines are set up for a particular operation, several sets of parts are prepared at a time. The ILS usually keeps machined parts “in stock”. Criteria: A considerable amount of time went into advance planning for designing and building turnouts. Guidelines were first established regarding the turnout design. Turnout design evolved with improvements made regarding the use materials where possible, simplify machine set up and lastly, simplify assembly. Various considerations have trade-offs. As such, the ground rules established for the ILS 7.5” turnouts were as follows: 1) Turnout design will make use of standardized parts 2) Material waste should be minimized 3) Quick assembly requiring few special tools 4) Functionality will take precedence over appearance and finally (but most importantly…) 5)
Turnouts must be reliable AND require little to no maintenance while
eliminating lubrication! Readers will note there has been no mention of cost, yet. While the club tries to minimize the cost of each turnout, cost was one of the previously mentioned trade-offs. Assuming all materials had to be purchased outright, a complete turnout (including switch throw mechanism) would probably COST in the $150-175 range. Members are extremely resourceful when the call goes out for supplies. Much of the materials used to fabricate turnouts came out of home/work shops as a donation as long as material sizes were acceptable. As a result of volume purchases, discounted materials and donations, the ACTUAL cost of the turnouts to the ILS has been much less. Pre-Machined Parts: Starting with parts preparation, photos 10 and 11 show a machined frog (ILS pattern for mainline frogs are #8.5). The casting draft has been cleaned off where the closure rails and heel extension rails will be attached. The pattern for these frogs was redesigned to provide a heavier mounting flange, proper flange throat clearances and full height tabs on frog ends to attach closure and frog heel extension rails. The trade-off, mating rail parts require that the rail foot be removed to mate with the frog casting. #10 clearance bolt holes have been drill for rail connections. #8 bolts with nylok nuts are used for the final connection. The oversized holes provide a loose fit for the bolts. This makes future bolt removal easier. (click all photos for larger view) Photo 10 Points: Photo 12 shows the switch point ends. ILS points are made of 1” stainless steel angle (see criteria 4 & 5). This material doesn’t rust, needs no lubrication and lets Mother Nature clean when it rains. Some club members were concerned about wheel contact area on the narrow edge of the angle. The distance a wheel travels on the angle edge alone is very short. The backside of each point is tapered to “nest” in the stock rail. After milling, the tip of the point is about .062” thick (half original material thickness). This is enough material for wear without machining a knife-edge that can crack or break off. Throw bar mounting hole(s) are drilled and de-burred. The closure rail connecting bolt hole is drilled during the turnout assembly process. Photo
12 Stock Rail Notching: Photo 13 shows fixture used to machine the “notch” in the stock rails (left and right). These are the mating notches for the switch points. This notch is a taper as well. The fixture holds the rails in place at a slight angle on the machine bed during the milling process. In time, the notch in the stock rail will be worn down by the passing of wheel flanges. Photo 14 shows the stocks rails after this step of the machining process. Photo 13 Heel Block Mounting: Photos 15 & 16 show the location where the stock rail is machined for the heel block(s). The heel block holds the stock rail and adjacent closure rail together at the proper distance. The stock rail and closure rail heel block mounting holes will be drilled during the turnout assembly process. Photos 17 & 18 show how the point end of the closure rail is machined for the heel block and eventual attachment of the switch point. The closure rail end taper provides extra clearance for the back of wheel flanges as they pass over the heel blocks. Photo 15 Photo 17 Frog Rails: Photo 19 shows how the frog end of the closure rails and frog extension rails are machined. If you recall, the frog casting does not allow the foot of the rail to be located under the casting. This extra step in the machining process ensures the strongest possible frog casting. Once again, the trade-off is a little extra work on the frog mating rail components. Rail end bolt holes will be punched during the turnout assembly process. Photo 19 Tie Material: Club members will sometimes visit local lumberyards at the end of the season to “clean up” treated lumber that was cracked or checked. This sometimes yields a stack of lumber that can be purchased for 50 cents on the dollar or better! In necessary, the club will purchase a “bunk” of 2x6 boards (64 total) at one time. The ILS uses (4) 8-foot long, 2x6 boards for each turnout. After the boards are cut to their various lengths, they are ripped in half to make the ties needed. Tie Spacing Jig: Building anything in a “controlled environment” is easier than building something on the ground. The ILS has a special tie spacing jig for turnouts. This jig was built with a 27 ties per 10 feet of track as opposed to the club’s regular track building jig that is built for 25 ties per 10 feet of track. After determining whether a left hand or right hand turnout will be built, the ties are arranged in the tie spacing jig accordingly (see photo 20). Photo
20 Hole Drilling: Screw mounting holes are pre-drilled in the ties for the straight stock rail. Ties located in the point area and guardrail area, are NOT drilled at this time. Photos 21 and 22 show a simple fixture used to pre-drill pilot screw holes in the tie. Pilot holes are drilled for one rail ONLY using a staggered hole pattern. The other rail screw holes will be drilled during assembly. One of the fixture tie stops is adjustable to allow for rails with different rail foot widths. ILS has several different rail sizes and profiles. During the turnout assembly, the foot of the rail will be drilled in the point and guardrail areas. #10x1” hex head sheet metal screws hold the rails to the ties. These are driven with a hex head driver or better yet, a 3/8” Allen cap head bolt that had the threads removed. The cap head bolts can be heated and dropped in oil to harden. Without hardening, the bolt heads will wear after driving several hundred screws. A grinding wheel can be used to remove the worn part of bolt head to expose “fresh” edges. Photo 21 Closure Rails: Drilling jigs were made to located the (3) holes on the closure rail ends (see photos 23 and 24). Left-hand and right-hand drilling jigs locate the holes for the switch point connection and the holes for the heel block. All clearance holes are drilled for #10 bolt hardware. The jigs are clamped in place while the holes are drilled. The straight closure rail is then taken to the saw where ¼” is removed from the FROG end. Both straight and curved closure rails are punched with slotted holes for attaching the closure rails to the frog. The slotted punch holes are sized for #8 bolts. The curved closure rail is then curved slightly (to approximate the 72 foot radius for #8 frog). Photo 23 Point Attachment: With the closure rail and switch point rail on a flat surface, the point is clamped to the closure rail so the closure rail bolt hole location can be transferred to the switch point (see photo 25). A #10 bolt clearance hole is drilled thru on a drill press. The hole is de-burred after drilling. The point is attached to the closure rail using a #10 round head bolt and secured with a nylok nut. The nut is left slightly loose to allow for point movement. Photo 25 Heel Blocks: The switch point is set against its mating stock rail so there is a 1/8” gap between the end of the point and the stock rail notch edge. The heel block is placed between the closure rail and stock rail. A #10 bolt is inserted in one hole to maintain alignment while the other hole is drilled through the stock rail. The assembly is clamped for drilling (see photo 26). The alignment bolt is then moved to the first hole so the second hole can be drilled. Photo 26 Assembly Begins: Photo 27 shows all the components in their relative position before the final assembly process begins. The curved stock rail, closure rail and frog extension rail have all been pre-curved to approximate the radius of the turnout curve (about 72 foot radius). Readers will also note that several rail ends are a little longer. This is done so that all turnout rail ends are staggered (not parallel). This creates a stronger track joint and minimizes rail kinks when the turnout is located in a curve. At this point, all the rails are fastened together. #8 bolt hardware and nylok nuts secure the closure rails and frog extension rails to the frog casting. #10 bolts and nylok nuts secure the heel blocks in between the closure rails and the stock rails. All of the rail pieces have now been connected. Photo 27 Rail Gauging: Special gauge locations are measured from the tip of the point and marked on the straight stock rail. Three (3) special gauges (blue) are set in-place that “fix” the distance between the stock rail, the curved closure rail and the straight closure rail. This establishes the gauge of the straight route at 7-9/16” and the radius of the turnout curve. Other gauges are set in-place; 7-9/16” gauges (white) are used at the ends the turnout. 7-5/8” gauges (orange) are used at the points and thru the curved portion of the turnout. Photo 28 shows the turnout (still not fastened to the ties) with all the gauges in place. Photo 28 Rail Fastening: A zig-zag pattern is used to screw the rails to the ties. After the straight stock rail has been screwed down, the ties are drilled and screws inserted from the switch point up the curved closure rail to the frog. Holes are then drilled and screws inserted down the straight closure rail to the switch point and then the same process up the curved stock rail. Photo 29 shows the turnout now with all the rails fastened and the point throw bar installed. The nylok nuts that hold the point throw bar in place are left loose to allow for point movement. Photo
29 Guardrails: The center of the guardrail is located opposite the frog point. Guardrail mounting holes are marked and drilled to correspond with the ties. Another gauge is used to simulate the wheel back-to-back distance. With one of the simulated “wheel flanges” in the center of the frog flangeway, the back of the other “wheel flange” is used to locate the guardrail position. Pilot holes are drilled in the ties and screws inserted to hold the guardrail (see photos 30 & 31). Since there is no space for a screw between the guardrail and the rail foot, the outside rail foot is drilled with a pilot hole for the rail screw. The rail foot hole is then enlarged for the #10 tie screw. Photo 30 Point Slide Shims: A similar treatment is given to the stock rails where the switch points are located. Once again, a pilot hold is drilled through the rail foot and into the tie. The rail foot hole is enlarged to allow the installation of a #10 track screw. Before the rail is screwed down, a stainless steel slide shim is installed under the rail foot for the points to slide on. Rail screws are inserted and tightened. The other end of the slide shim is attached with a nail or track screw as well. Head block spacer bars are installed to maintain the distance between the head blocks AND keep ballast out from under the point throw bar (see photos 32 and 33). The turnout is now assembled. Photo 32 Switch Throw: Photo 35 shows the point throw mechanism arrangement. Once again, “exotic” materials are used (nylon, aluminum, stainless steel and a bronze bushing), to make a mechanism that doesn’t need lubrication. With the exception of the mounting screws, there are no ferrous metal parts used in the entire assembly that will rust or require lubrication. A hitch pin is used to connect the throw rod to the throw bar. Spring tension is set to insure point closure when a train “trails” the turnout with the points thrown against the running route. This is adjusted again when the turnout is installed and ballast work completed. Photo 35 Turnout Complete: Photo 36 shows a railhead view of the completed turnout. At 14.5 feet in length, two persons will be needed to carry the turnout outside to stack and wait to be “planted” in the railroad. Photo 36 |
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