The shortest bridge would span the back door to the yard. This is a standard 36" exterior door, that opens from the left to the right.
As there is area on either side of the door that benchwork can be permanently installed, it was decided that we would test our process here first.
In casting around for a way to anchor the ends in a removable way, the engineering shops at the Western Maryland Moseley Division (WMMD) were consulted. Their answer was to use a door hinge as it would serve the dual purposes of alignment and removal.
We decided that we would just aim for a simple, lift in and out style bridge.
As the track curves in this area, we needed to make the bridge wider on one side.
A landing block was afixed to the benchwork to give a reference and stop point to the plywood that acts as subroadbed as well as give us a place to mount the hinge. A piece of 3" wide, 3/4" plywood was used as horizontal stiffener by mounting it vertically under the subroadbed.
|West side, showing the hinge used to an anchor point.|
|East side; this area is only 4 inches wide.|
|Finished product. Note the horizontal stiffener.|
After the install and test fitting, the entire assembly was painted with oil based paint to seal it against any humidity changes so it won't become larger or smaller and no longer fit.
A further update will show how roadbed and track have been installed.