Scale and Scope: An Impressive Undertaking
The Pacific Desert Lines stands as a testament to persistence and vision, representing fifteen years of continuous development by the San Diego Society of N Scale. This remarkable achievement encompasses 1,137 square feet of meticulously crafted layout area—an impressive footprint dedicated solely to the railroad itself, not including the surrounding aisles and access areas that facilitate operation and viewing.
The railroad’s scope becomes even more impressive when considering its scale distance. The mainline trackage stretches an astonishing 33 scale miles, which translates to 1,089 actual feet of track carefully laid throughout the layout. This extensive mainline accommodates both continuous-run operations via a ten-scale-mile loop and prototypical point-to-point operations covering approximately 12 scale miles between terminals.
Complementing the visible portions of the railroad, an additional 2.1 scale miles (70 actual feet) of hidden track provides crucial staging areas where trains can be prepared and stored between operational sessions. The branch line adds further operational interest with its 1.55 scale miles (51 actual feet) of track serving various industries and communities away from the mainline.
Track Standards: Precision Engineering in Miniature
The Pacific Desert Lines maintains exacting standards in its track configuration, reflecting prototypical railroad engineering practices scaled down to N scale proportions. Turnouts (track switches) are designed with a minimum size of No. 6 throughout the layout, while mainlines and passenger sidings feature more gradual No. 8 turnouts to accommodate higher speeds. Crossovers between parallel tracks utilize even more gradual No. 10 turnouts for smoother operation. In specialized locations, the layout incorporates curved turnouts reaching up to an impressive No. 18 size—a remarkable achievement in N scale track construction.
Track Construction: Craftsmanship and Innovation
All visible trackwork throughout the layout employs code 40 rail (referring to the rail height in thousandths of an inch), mounted on a combination of wooden and printed circuit board (PCB) ties. This finely-scaled rail creates a remarkably realistic appearance. Rather than using commercial track products, the rails are soldered directly to the PCB ties, which are strategically placed at every fifth tie position for electrical conductivity and structural integrity. Turnouts are built in place using specially positioned PCB ties, allowing for custom geometry and reliable operation.
For hidden staging areas, the layout utilizes commercial code 55 flex track with hand-made turnouts, balancing reliability in less visible areas while maintaining quality standards throughout.
The railroad’s commitment to craftsmanship is perhaps best illustrated by the staggering total of 274 turnouts—all hand-made rather than purchased as commercial products. Each turnout is powered by a Fulgurex mechanism, providing reliable remote control of train routing throughout the layout. This represents thousands of hours of skilled labor dedicated to just this one aspect of the layout construction.
Roadbed and Structural Design: Lessons from Experience
The Pacific Desert Lines’ structural design reflects lessons learned through years of operation in the museum environment. The trackage rests directly on either 3/4-inch plywood or laminated splines constructed from 1/4 × 1 inch pine strips. For mainlines requiring the addition of ballast, the track is elevated on 1/8-inch door skin (thin plywood typically used for covering hollow-core doors).
Notably, the layout deliberately avoids traditional cork roadbed material. This design decision stems from practical experience with the museum’s fluctuating humidity levels, which caused problematic expansion and contraction in cork roadbed installations, resulting in rails breaking loose from ties and other maintenance challenges. The current design prioritizes stability in the variable environmental conditions of a public museum.
Project Status: A Work in Progress
After fifteen years of development, the Pacific Desert Lines has achieved significant milestones, with approximately 90% of the extensive trackwork now complete. The equally important scenic elements have reached about 60% completion, transforming the railroad from mere track infrastructure into a compelling visual representation of Southern California’s diverse landscapes.
This ongoing development illustrates the nature of large-scale model railroad projects—they are never truly finished, but continue to evolve and improve as techniques advance and new details are added, ensuring that visitors to the San Diego Model Railroad Museum will discover new features with each visit for years to come.