To get a comprehensive layout plan I compiled and mapped all details I had on the CNJ Bronx Terminal track system, the primary structures including the freight house and the Third Avenue Bridge, their integration into the Harlem River waterway and the street system of the South Bronx. The image below shows the result.
Things that I had to consider when working out the details:
- The track radii are tight: the inner circle track has a 90 feet radius, the outer circle 104. The tracks to the transfer bridge at some point have an 85 feet radius.
- The density of turnouts in the freight yard is unique and to build them prototypical may be a challenge due to limitations of the (N) scale, the rail (code 55), and of tools and techniques used. I figured out that the minimum distance of the two throw-bars in a 3-way turnout must be about one inch. In some cases I might have to use hinged point rails in order to reduce pressure on the throwbar.
- The resulting complexity of the geometry of some specific combinations of turnouts is going to be a challenge. Probably the most complex pair of turnouts is the crossover from the inner to the outer circle track and 3-way turnout leading to tracks 7 and 8. I’ll see if it’s feasible.
- The distance between the team and the two concentric circle tracks is sub-standard as it was set when freight cars were considerably smaller. Based on measurements and tests I’m assuming a distance of a little less than an inch (24 mm) between the two track axes for team tracks and slightly more than an inch (27 mm) for the concentric tracks in N scale. This corresponds to a prototypical 12.6 feet (3.85 m) and 14.2 feet (4.32 m). This also correlates roughly with the a measurement on the CNJ Bronx Terminal Plan which gives a distance of 12 feet between tracks 13 and 14.
- As Tim Warris has explained and shown in great detail, the removable crossover to the engine house was a unique design. To keep things a bit simpler, I will not model this lead track and will omit the engine house altogether.
- The track on the Northwest side leads to the CNJ freight yard extension that was added at the end of the 1920s between Harlem River and 135th Street. It passes under the Third Avenue Bridge in a tunnel through the abutment. I will model this track and the tunnel but for the time being will continue it along the layout edge. This will give me a bit more room to operate freight cars on tracks 15, 16, 17, and 18 (the track to the transfer bridge).