instructions 1:48 O-SCALE THROUGH PLATE GIRDER BRIDGE IN DURANGO CO 2017 John Palecki Structures rev 1.1
CONGRATULATIONS ON YOUR BRIDGE PURCHASE! YOU ARE about to assemble a 1:48 O scale model kit of a typical through plate girder bridge. These simple bridges are very common across the world. Plate girder bridges can have the main support structure under the track if clearances below permit as on a deck girder bridge. Or, in this case, the track runs between the plate girders to create minimal bridge depth. Plate girders are the large side sections of this type of simple beam bridge. The solid sheet of metal that makes up the plate can carry considerable weight even though they may be an inch or less thick. But a thin metal sheet 6 tall and 20 long will be very flimsy. The plate needs stiffening so it will not buckle and fold even while supporting itself. The top and bottom flange angles and plates provide most of the stiffening strength. The plates have extra layers (pile-on plates) toward the bridge center to counteract the increasing edge forces toward the bridge center. The vertical angles add stiffness to the center of the plate. The bridge ends have additional stiffening angles because the supporting forces are concentrated over the abutments. The plates always have splices due to the mill capabilities of the early 20 th century. Some splice plates are large and plainly visible with numerous rivets. In this bridge some of the vertical stiffener angles have an extra layer with rivets underneath for joining the plate sections. This D&RGW bridge is an example of a re-used bridge as is common with most metal bridges on the system. It crosses the Animas River right in the town of Durango, CO. It was built to standard gauge proportions making the model suitable for most all O-scale modelers. You can visit the prototype. The Durango & Silverton uses this girder bridge and the adjacent metal and wooden trusses every day they run. Check out the web for videos showing the Durango & Silverton trains on this span. PROTO PHOTO instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 2
KIT WARRANTY FIRST, please inspect the parts carefully through the packaging before opening. Some parts are quite thin so until you are comfortable with them preserve their integrity with cautious handling. Spare parts are not easily available because of the variability of my production and the life time of the molds. JOHN PALECKI STRUCTURES WARRANTY: I am very proud of the quality of my kits. I personally packed your kit with care. I also inspect every part before it is packaged and boxed. DEFECTIVE PARTS: If you find a part that cannot be assembled due to manufacturing defects, I will replace the part. Moderate flash or occasional breaks are typical of the thin castings and will not affect the finished model. RETURNS: If you determine the kit is not what you expected I will take it back and refund your payment within 30 days of receipt of the kit, provided you purchased it directly from John Palecki Structures. Please note I cannot take back kits that have been started or have parts missing. SUITABILITY: Because I can not control how the modeler assembles, installs or uses this bridge model John Palecki Structures cannot assume responsibility for any results the modeler may have in the model, application or use of the model. The model is to be used indoors only and kept out of direct sun and heat. The warranty applies only to the original purchaser. This kit is not suitable for children. It is a complex model to be assembled by experienced modelers. John Palecki Structures 3339 Collingwood Street NE Roanoke, VA 24012 USA john@jpstructures.com (best way to communicate) 540-366-6470 Thank you for purchasing a John Palecki Structures bridge kit! instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 3
KIT CONTENTS LEFT HALF GIRDER (2 ea) RIGHT HALF GIRDER (2 ea) GIRDER PLATES (4 ea in pairs) FLOOR BEAMS (9 ea) CLEVISES (1 fret 3D printed).032 BRASS ROD for bracing rods (6) 5/16 STYRENE I-BEAMS for stringers (5) CD-ROM with the instructions and photos instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 4
INSTRUCTIONS INDEX SECTION ONE: Pre-assembly 6 SECTION TWO: Girder Assembly 9 SECTION THREE: Floor Assembly 15 SECTION FOUR: Bracing Rods 23 SECTION FIVE: Paint & Track 26 instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 5
SECTION ONE: Pre-assembly-1 Bridge Kit Basics The bridge consists of three major assemblies: two plate girders, and the floor system. The track is a separate assembly (provided by modeler). The floor system supports the ties & rail using floor beams (9) & stringers (4 per 8 panels plus end brackets). Note: In bridges each section is called a panel. One girder is the assembly of left girder and right girder castings and the top & bottom girder plates. The bottom has bracing rod details with clevises. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 6
SECTION ONE: Pre-assembly-2 Tools & Supplies The primary tools for assembling a bridge kit are quite simple but essential: 1. Razor saw- This is needed to remove the heavy cast on sprues from the floor beams and girder sides. A fine-bladed band saw can also be used. 2. Adhesives- Instant or superglues, referred to as ACC (alpha cyanoacrylate cement) will create a strong joint on resin castings and 3D prints. (Styrene solvent adhesives do not work on resins.) ACC comes in various thickness and setting times. I suggest using the medium thickness ACC adhesives in most joints because of the slower cure time. Your personal experience will guide you. Most connections require only a very small amount of adhesive. Try to avoid the use of accelerant because it affects paint adhesion. 3. Calipers- Accurate dial calipers are necessary for cutting to length some parts and checking dimensions. 4. Other tools- Sharp hobby knives, tweezers, large & small files, fine sandpaper, pin vise, Dremel tool with bits, whatever is in your modeling tool box! 5. Work surface- I use a work surface made from a 36 white shelf and an aluminum angle screwed to the back edge. The angle was installed very straight so it can be used to align bridge models. 6. Track makings- There are various ways to make track from simple to complex. I leave it up to the modeler to supply track materials to their liking for all the bridge kits. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 7
SECTION ONE: Pre-assembly-3 1. Read through the instructions before starting. Get comfortable with the assembly. 2. Leave all the sprues on the parts until needed. Handle parts carefully at all times to avoid breaking off the thin plates on the floor beams. The printed clevises are pretty fragile due to the characteristics of the printing method. 3. Keep the parts and assemblies away from heat and constant direct sun. 4. The kit was designed on a computer and the master parts were precisely made via 3D printing. However, mold rubber and resin change dimension slightly after curing. Slight adjustments, trimming and cleaning will be necessary. 5. Double check part locations before bonding. AC adhesive bonds the castings quickly! 6. The resin is a high-quality, high-strength material but you may break things during construction. I designed it with realistic thin sections so some part extensions are fragile. Just glue it back together, scrape the excess glue off and paint it. 7. The castings may contain an occasional pinhole. In this kit they have been primarily in spots that will be hidden by another part. I always vacuum the resin mix and, on some parts, the mold is vacuum cast to remove air. But there may be a stubborn tiny bubble that shows itself that needs filling. 8. Keep an eye on alignment at all times so the bridge does not develop a twist as you assemble it. 9. The bridge can easily carry the weight of your locos without reinforcement. Please assemble it carefully! instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 8
SECTION TWO: Girder Assembly-1 Prepare the left & right girders castings for assembly. 1. Cut the casting sprues off the left & right girders at the shoe plate, and girder bottom. 2. This sprue style does not need end squaring but clean off any flash. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 9
SECTION TWO: Girder Assembly-2 Clean up all the girder surfaces. 3. Sand and file the sprue areas so they are flat and clean. 4. Clean any flash off and fill the occasional pinhole if it will be visible. 5. If the sides have a bit of a twist or bow, do not attempt to straighten them. They will be held straight by the floor beams. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 10
SECTION TWO: Girder Assembly-3 Remove the sprues from the girder plates. Keep the ends square while filing or sanding 6. Cut the girder plates away from the sprues. 7. Remove any thin flash (sharp scissors work well). instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 11
SECTION TWO: Girder Assembly-4 Align and glue the girders. This flat area on both top & bottom should be straight. 8. Line up a left & right girder half on a flat surface. Line up the FLAT area on the upper or lower edge. (The rivet bumps toward the ends will cause misalignment.) 9. Apply a touch of glue to hold them together. Verify the alignment. Add more glue. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 12
SECTION TWO: Girder Assembly-5 Align and glue the girder plates. Girder plate Last rivets Girder plate Last rivets Girder plate mid point is here 10. Test fit a girder plate. It is to be aligned equally between the last row of rivets on each girder half. The center of the girder plate can be found by looking for the paired rivets as shown. 11. Glue both the girder plates in place. Use a slower setting AC adhesive so you can align them. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 13
SECTION TWO: Girder Assembly-6 Complete the girder assemblies. 12. Repeat 8-11 for the other girder. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 14
SECTION THREE: Floor Assembly-1 Prepare the floor beams. Remove part line flash Hold the floor beam and cut -OR- Hold the end sprue in vise and cut 1. Remove the large end sprues with a fine bladed razor saw or on a good band saw with a fine blade. 2. File and sand carefully the cut surface so it is flush to the end flange and square to the lower flange plate. 3. Remove as much of the part line flash on the riveted surfaces as you feel necessary for good appearance. 4. Check the fit on a girder and clean up as needed. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 15
SECTION THREE: Floor Assembly-2 Prepare the floor beams for assembly to the girders. Fits between edge flange and splice plate detail Fits between edge flange detail Scrape or file this edge both sides 5. The floor beam flanges fit in full contact with the girder sides. There is a space provided in the girder detail. 6. The floor beam flanges may need to be trimmed slightly narrower to fit. Scrape, file or sand the flanges to fit. Do them all now for ease of assembly. 7. Also check the stringer pockets with a piece of the styrene I- beam now while it is easier. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 16
SECTION THREE: Floor Assembly-3 Prepare end floor beams (2) specially to fit under the girder top flange curve and on the lower flange pocket. Top filed to a curve to fit under girder flange Girder inside Gusset Girder outside Gusset trimmed flush Narrow slot Remove this one rivet in the corner Slot must fit over angle 8. Trim the floor beam gussets on one side so it is flush with the bottom flange. 9. Carefully cut a narrow notch into the other side of the gussets so they fit over the girder angle. 10. File the bracket tops to the correct curve to fit inside the girder. Gusset trimmed flush to floor beam flange on this side instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 17
SECTION THREE: Floor Assembly-4 Cut the styrene I-beams for stringers. End panels 1.849 1.877.235 Brackets 11. Cut the styrene I-beam stringers to these lengths: 24 @ 1.877 (mid panels) 8 @ 1.849 (end panels) 8 @ 0.235 (outside end brackets) Mid panels instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 18
SECTION THREE: Floor Assembly-5 Attach the first floor beams with stringers to the girder. Start in the middle of the bridge. First floor beam Don t glue the stringers yet! Second floor beam 12. Glue one floor beam in place. Check carefully for squareness in all directions. 13. Insert mid length stringers but do not glue yet. 14. Fit the stringers into another floor beam. 15. Glue the second floor beam in place checking again the alignment. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 19
SECTION THREE: Floor Assembly-6 Continue adding stringers and floor beams. Don t glue the stringers yet! 16. Continue with all the mid length stringers and floor beams. 17. Add the end floor beams and shorter stringers. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 20
SECTION THREE: Floor Assembly-7 Fit and glue the other side girder. Line the floor beams up carefully before gluing 18. Line up the floor beams and opposite side girder. 19. Use rubber bands to hold the assembly together. Check all floor beam fits. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 21
SECTION THREE: Floor Assembly-8 Glue the stringers. Brackets 20. Flow glue into all the stringer attachment brackets. 21. Install the outside end brackets and glue. You are herelooks like a bridge! instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 22
SECTION FOUR: Bracing Rods-1 Prepare the bracing rods and clevises. NOTE: The clevises are 3D prints. They are fragile. Note the detail orientation in the photo. Clevis bottom with cotter pin Clevis top Insert rod to here as shown. Completed brace rod 1.Cut the brass rod as follows: 12 @ 3.420 (mid panels) 4 @ 3.400 (end panels) 2. Insert a rod into a clevis and glue. Align the other end clevis in the same direction and glue. Refer to the insertion distance and detail orientation in the photo. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 23
SECTION FOUR: Bracing Rods-2 Install the bracing rods. Bottom view Top view Dimple Clevis bottom with cotter pin Floor beam gusset Clevis top Girder 3. Swing a rod clevis into position. A nub inside each leg of the clevis will engage the dimple in the floor beam gusset. 4. Apply glue carefully. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 24
SECTION FOUR: Bracing Rods-3 Install the bracing rods. Bottom view Top view 5. Install the remaining bracing rods. Make the under/over crossing of the rods in the center the same orientation in each panel. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 25
SECTION FOUR: Paint & Track-1 Painting. I am sure you will not need completely detailed painting info for this kit. Use your method and paint of choice, whatever you are familiar and comfortable with. Acrylic or enamel paint is OK. Other solvent paints should be tested first. Here are some painting ideas and suggestions: 1. Airbrushing is the most effective method of painting a bridge kit because it covers more thoroughly and quickly. A brush would work fine for touch ups and weathering. 2. All the castings were ultrasonically cleaned in a non-toxic grease removing solution. I need to use a silicone based mold release on these parts, which normally would interfere with paint adhesion. I had no problems spraying Polly Scale acrylic on my bridge after cleaning and assembly. You may carefully wash the castings or assembled bridge in luke-warm water (not hot!) and soap if desired. 3. I first sprayed a heavy black undercoat primer to blend in the 3D printing textures, glue remains, gaps, sanding marks, etc. 4. Bridges start as either black or silver. Some black bridges, such as this one, were painted over with silver but now the original black is showing through. Many railroads rarely or never repaint their bridges, allowing orange-brown rust to take over. Start with a coating of the base color, then weather using the method of choice. I use airbrushing, paint wash, artist s chalks and drybrushing techniques. A coat of matte sealer will protect the finish. 5. For weathering references, the internet is full of bridge photos. For techniques, see your local hobby shop and the variety of books available. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 26
SECTION FOUR: Paint & Track-2 Painted flat black. Painted silver then weathered instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 27
SECTION FOUR: Paint & Track-3 Track. Note: Track is supplied by the modeler. Suggestions are below. If you have specific data for this bridge and the year use it- the standards seemed to change over time. Ties: Mt Albert O-scale 8x10 Tie alignment boards: Mt Albert O-scale 4x8 NBW: Black Bear GL-5123 (round) or Tichy 8082 (square) Rail: Code 83 (gauged 36 here) Spikes: Micro-Engineering Micro Spikes 1. Pattern is seven ties evenly spaced per panel. 2. Ties are mounted on edge. 3. Tie length is 10ft (2.5 ) 3. NBW detail are staggered. 4. One tie at each end supported by brackets. 5. Ties are close to or against floor beam flange. 6. Leaving the track loose on the bridge for easy removal is a good idea. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 28
SECTION FOUR: Paint & Track-4 Track. Track installed. instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 29
COMPLETION Install the bridge on your choice of abutment. Generally a bridge this size would have simple sliding feet. The cast-in blocks on the girder ends are sufficient. I hope you enjoyed your kit building experience. I welcome your comments and photos. Your suggestions are how I can improve future models so please let me know what you think. Thank you, John Palecki instructions: 1:48 O SCALE 80 DURANGO THROUGH PLATE GIRDER BRIDGE page 30