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es were plumb and parallel, I placed a piece of plywood across the top of the trusses and added weight. The glue was left to cure for 24 hours.


The remaining floor beams were in- stalled, remembering to get the differ- ent lengths in the correct positions. Four of the beams, evenly spaced along the bridge, extend 4′-0″ outside the lower chords of the outer two trusses and support the diagonal bracing tim- bers that keep the trusses vertical. At the outboard end of the bridge the last six beams extend outwards by 3′-6″ to support the two winches. All of the other floor beams extend a dis- tance of 10″.


At this point, I went back and threaded the tie rods down through the holes in the top chords into the corre- sponding holes in the lower chord. Adding the n.b.w. castings and bearing plate detail to the top surface of the trusses came next. There are three tie rods at each point on the chords where only diagonals meet. Where there is a vertical post between panels, and at the vertical posts at each end of the truss, there are six, three on each side of the vertical posts. I skipped the bear- ing plates on the bottom of the lower chord since they were not visible.


Floor


The floor beams are supported under the trusses by U-shaped hanger bolts. These pass through the spaces be- tween the lower chord’s timbers and through steel bearing plates on the top of the chord. There are two of these hangers at each truss, a total of six on each floor beam. I only modeled the outermost two at each beam; the rest would be hidden from view. However, since they are easily seen, each plate on the top surface of the lower chord is there and has four bolt heads. Addi- tional steel reinforcing plates were po- sitioned along most of the length of the lower chord on the two outboard truss- es only. These were bolted to each other through the chord. The photos should make all of this clear. New York Harbor marine transfers were arranged with the track on the right side of the float bridge continu- ous through the length of the bridge and onto the barge. The left track had the switch points for the center track of three-track car floats, but the frog for the switch was located on the car float itself. The points were thrown using a low-profile switch stand on the floor of the bridge. With the crosswise floor beams in


place, the 8″×16″ stringers came next. I started with those for the two main tracks. For the lefthand side I trimmed some additional stringer stock to a ta-


RAILROAD MODEL CRAFTSMAN


The view of the finished bridge gives a good idea of just how much timber was needed to build the float bridge and finger piers. Note that this picture was taken as the model was being readied for transport to the NMRA Convention at Hartford, Connecticut, thus you may just be able to make out the twine holding the model firmly on the base. At this point the apron was not complete, which is why it’s not in the picture.


per and glued it down to support the diverging track. Note that all three sets of rails have guardrails at the out- board end of the bridge. Since my mod- el was semi-permanently installed on my layout I did not add these (another discrepancy I could live with). The 8″×12″ wooden guard timbers


were glued on edge along the outer faces of the stringers. I planked the re- maining open areas of the floor, run- ning the boards parallel to the trusses and stringers. The prototype used 4″- thick planks and raised them up even with the tops of the stringers with packing blocks on the tops of the floor beams. I used 6″-thick planks to make the stringers a little more pronounced in their appearance. Since I only have a station float (a


float with a center platform and two tracks, described in the November, 2011, RMC), I soldered the righthand point rail to the stock rail to provide good electrical continuity on the bridge. If you want, or need, to use three track floats, you will have to make the points operate. I’m sure it is feasible, either by mounting a switch machine under the layout and bringing the throw wire up or by some other means.


When laying the rail on the bridge I


notched out enough clearance in the timber under the rails to allow a rail joiner to be slid into place. It keeps


things rolling smoothly, as the rails al- ways line up.


There are four diagonal braces on each side of the bridge that run from the ex- tended floor beams to the top chord of the two outermost trusses. I formed the steel straps that hold these in place from .005″ styrene and n.b.w. castings. With this done I went back over the model with a fine, pointed brush and stain, touching up all those little bits of ex- posed, raw wood on the cut ends. When I installed the rails I made them flush with the outboard end of the bridge, but let them run long at the inboard end so there would not be an obvious joint at the end of the bridge floor. I put Kemtron tie plates under the rail when I spiked it down, but I’m sure if you didn’t want to go to the trouble of making your own tie plates it would look fine to just spike the rails to the stringers. By this time, four or five years had passed, as it took me nearly three years to finish the draw- ings, only working on them occasional- ly. It was finally time to consider the hardest part of the model, constructing the two mooring winches at the out- board end of the bridge. From the be- ginning I suspected they might present a problem. These mooring winches hold the car floats to the end of the bridge. The problem was not so much building a winch, it was finding sufficient small gears to make two of them.


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