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Division 1: Mark Ward 2007

How time flies when you are having fun. Please accept my apologies for not updating the ongoing story of the construction of the Oma Belt on a more regular basis.
    Since the middle of 2005 (my last update posted), the continuation toward a 'more complete' railroad has been evolving quite well. The peninsula mountain containing the spiral has been half completed and the effect on the physical volume of the railroad was immediate. As trains leave Rock Ridge westbound, they enter a long tunnel which contains the height gaining, totally hidden to the railroads viewer, single loop spiral. Completing 360 degrees and climbing at an average of just over two and a half percent for the length of the spiral, trains emerge from the western portal to almost instantly go across a 185' curved, inclined, ballasted deck girder trestle (not a lot unlike the Foss River bridge on the western side of the Cascade crossing of Stevens Pass). This trestle was a project in itself took three weeks to construct, not including the towers under the structure.
    A little background here - In mid 2005, before going on to a work convention in Las Vegas, my wife and I spent an amazing 10 days railfanning in the Fraser river area of Canada and the Stevens Pass area of Washington state in the United States. Whilst there, I was determined to take particular notice of the way that the Great Northern had constructed the many bridges through Stevens Pass. I had for a long time, noticed that when trains were photographed from any height in a shot depicting the traversing of a bridge, unlike a lot of other viaduct/deck girder type bridges, there was no visual access through the cross ties whilst on the bridge. The bridges were bridges alright, but straight or curved, high or low, they were ballasted! I was determined to replicate this construction method for the four 'smaller' bridges on the Oma Belt. Micro engineering puts out a simple concrete type bridge deck for this purpose, but all of the bridges that I am interested in are timber on steel. So, whilst deep in the magnificent scenery of Stevens pass with endless miles of breathtaking mountainous vistas to gaze at endlessly, I was also taking photographs of the undersides of bridges, their supports and abutments -- my wife thought I was nuts! Back home, those photographs have proven invaluable and provided the key to unlock the secret of constructing strong, yet aesthetically pleasing, correct looking bridges which met the prototypes intent.
    Once across this curved, inclined, ballasted deck girder bridge, trains pass through a short tunnel which is basically at viewers eye height -- you really can stand right up to it and look all the way through. Again, I have admired the way that in some photographic contests, the subjects have been captured on the far side of a short but 'complete' tunnel. What is complete? Try fully weathered, ballasted and detailed trackwork, tunnel interior with rock details and correct colorations from one end to the other. This sounds terrific and easily made the short list of desired elements of the Oma Belt in the planning stage, however dreaming of and visualising it was one thing, constructing, well that was yet another modelers engineering challenge to be overcome.
    To cut along story short, after much deliberation of methods available, the tunnel was built on two removable platforms which were both (once again) curved and inclined and had to be constructed for that exact location, neatly fitting the side profiles of the long ago constructed roadbed/risers of that area. Once braced, using the two blasted rock portals and a top mounted spine between them, the entire construct was lifted out and taken to the workshop. At this point, now upside down, the tunnel internals were made, painted/colored and detailed.
    Before the construct was replaced into position, the trackwork through that zone was ballasted and weathered. By using masking tape applied to the vertical sides of the roadbed, I ballasted to a vertical edge on both sides of the track (which would be inside of the tunnel), still allowing the tunnel construct when completed, to be put back into place. Once fixed into its correct position, using a double length oversized straw, I 'flowed' more ballast into both sides of the tunnel (from either end) and completed the ballasting process from the previously finished sides, joining to the tunnel walls themselves. Gluing down that ballast was completed in a similar fashion. A lot of work, but well worth it when I can see visitors looking into the tunnel with a perplexed look in their eyes saying 'how did he do that?' Building this layout in a straightforward manner was never the intent!
    Exiting that short tunnel, the track goes over a fifty foot long ballasted deck girder bridge and then completes the climb as the grade levels out into Laurence. Laurence has a short passing track and has a spur for the grain elevator located here. Some changes were made to the original scenic plan here, whereby the fascia was cut away a little further to have a river curve on and then subsequently back off the layout, adjacent to, but well below the trackwork. I have also lengthened this passing track from its initial completion by using a curved #8 turnout at its western end. Length gained here was only about three feet, however work trains make it a practice of being in the hole here for east and west bound traffic. This is the last area for passing trains before west bounds continue onto the longest section of single track mainline on the entire railroad.
    By this point, trains have now gotten into the 'real' mountains of the layout. Scenery on the next fifty feet of mainline goes from four to eight and a half feet in height (the room's roof height is nine feet). Indeed, one of the prime directives of construction for the layout was a high scenery to track ratio. In one area here, there is almost 60 square feet of scenery for only nine feet of track. This area has been the focus of our efforts for the last half of 2007. To cope with the sheer height of the scenery when in construction, using the original 'joists' constructed on the L and T girder bench work, 6mm MDF board was cut to profile and attached to the bench work joists at approx. 15 inch intervals. These give a vertical, three dimensional location for the cardboard strips used in mountain terrain construction to be attached to. The cardboard strips are now almost complete and have had had the nylon fly screen mesh attached to approx 60% of the cardboard web to date. Although this does absorb a little more time, the mesh serves as a screen to the wet plaster when laid and allows next to nothing to permeate through onto the completed bench work/wiring etc below. More work now, less work later!
    Upon departing the lengthened passing siding at Laurence, westbound trains enter another tunnel. The mountain containing this tunnel disguises the only point on the railroad where the track crosses over itself, therefore what has always been an absolute layout design 'no-no' is avoided. Trains reappear four feet past the lower track tunnel and being almost 18 inches higher than the lower track at this stage, the two tracks in the one scene is (almost) tolerable...
    Exiting that tunnel, trains pass along a precarious very steep part of the mountain, where the track is supported by a 90 foot long stone retaining wall. Then it is into another blasted tunnel before continuing on toward the next large curved deck girder bridge which is yet to be constructed. Making their way over that bridge, trains proceed through a very closely cut rock cutting before going onto the 175' curved chord truss bridge with another 60' approach deck girder on the western side. Adjacent to this is the highest point of scenery on the layout and thoroughly fills the eyes of visitors after entering the room and turning left. Even when viewing these mountains from twenty five feet away, they sure are attention getters!
    Curving off that bridge combination, the line enters Monroe, where urban scenery will (like the main yard area at Peyton -- now directly below Monroe) dominate the visual interest of the viewer. We are hoping to commence on the urban scenery (my original favourite part of the hobby) in late 2008.
    Until then, best wishes to all in your model railroading endeavors.
    Mark Ward