Sunday, June 1, 2014

SALMON CREEK MAINLINE BRIDGE – 2


The ballasted deck girder bridge for the mainline over Salmon Creek was completed with construction of the piers and abutments and installation.  My previous post on this bridge discussed the deck and girders. http://espeecascades.blogspot.com/2014/04/salmon-creek-mainline-bridge-1.html
This current post describes the piers and abutments and final installation.

I built the piers and abutments out of styrene, mostly using 0.060 inch styrene sheet.  The piers for the deck girder bridge were narrower than the piers I built for the main Willamette River crossing between Eugene and Springfield. http://espeecascades.blogspot.com/2013/11/bridging-gap-willamette-river-bridges-1.html 
Those piers were wide to account for the through truss spans.  The deck girder footprint is much narrower, making these piers too narrow to clamp for work in my cross-compound miter saw.  That led me to styrene construction for the current effort.


Deck girder bridge with piers under construction.

The first picture shows the piers under construction.  Styrene square tube was used to separate the top and bottom plates at the correct height.  The sides and ends were then sheathed using the aforementioned 0.060-inch styrene sheet, overlapping at the joints.  The overlaps were sanded smooth with the joining surface, providing a solid appearance.  A similar technique was used for the abutments at the bridge ends.  Both piers and abutments have a 12:1 batter (slope) per Southern Pacific Common Standard drawings for such concrete work.

The piers and abutments were finished with paint and weathering powders.  Several weathering passes were made with both paint washes and Bragdon powders.  I may apply yet another coat of a concrete-gray powder, as the rust effects are bit heavy yet.

With the piers and abutments ready, I installed them and the bridge, affixing all with Dap 230 adhesive caulk.  This adhesive will allow me to remove these pieces later, albeit with some effort.  I then installed cork roadbed (the beginning of the ballast) on the deck and continued on up the spline subroadbed grade.  After sanding the cork, I applied gray paint, mostly as a color primer for the eventual ballast installation.  Finally, I formed flex track and installed it, completing the job with electrical feeders.


First train over Salmon Creek.

I continued the track laying up the grade.  I sandwiched tulle between the spline subroadbed and the cork.  Tulle is better known for its use in wedding veils.  It is fairly inexpensive.  My wife used it as part of a craft project for house decoration, knowing it would get recycled by me into the railroad.  The tulle provides an equipment catcher for now.  Eventually, it will help form the terrain, providing a foundation for a proper railroad grade, including drainage ditches.


SP X-9325-W arrives at End of Track on the climb up out of Oakridge.  Note the tulle (bridal veil material) sandwiched between the spline subroadbed and the cork roadbed.

My railroad has begun the climb out of Oakridge.  I’ve also begun benchwork for the upper level: Cascade Summit and Crescent Lake.  I plan to build from both ends, eventually meeting mid-grade.

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