The Mushroom

The advantages of a Mushroom style layout are pretty obvious.  First and foremost is the height of the layout in relationship to viewing angles.  As can be seen in the drawing below, the lower level is set at 48" above the floor and the upper level is set at 53" above the elevated floor (21").  The second advantage is that one scene doesn't protrude or interfere with the other since the upper and lower levels are viewed from opposite sides.  On the other hand, there are disadvantages.  First, you need a reasonable ceiling height.  In my case, the ceiling height is 100" which I believe is close to the minimum for someone of my height, 6'3".  In addition, construction is certainly more complex than a conventional layout and for obvious reasons it won't work on perimeter walls.  

 

 

First Post - Backround Info & Track Plan

Backround & Track Plan

The Madisonville, Bowling Green & Chattanooga Railroad is an HO scale layout representing a regional free-lanced railroad set in Kentucky and Tennessee during the early 1990's.  In the north, it interchanges with the Paducah & Louisville and the CSX at Madisonville, KY.  From there, the line heads south to Memphis Junction (Bowling Green, Kentucky) and interchange with the Illinois Central and CSX.  From Bowling Green the line heads southeast, over the Cumberland Plateau, and on to Chattanooga, Tennessee and a connection with the CSX and Norfolk Southern. The layout represents the area around Bowling Green, Kentucky..

The main part of the layout will occupy a 27' x 16' room.  A second room, 12' x 6' will contain the staging yards, return loops, dispatchers desk and work area.  A Sn3 layout has occupied the space for the last 14 years. 

 

I generally don't care for double level layouts due the height limitations.  For me, the lower levels are generally to low or the upper levels are to high.  My plan overcomes the problem by using a "Mushroom" style design with a raised floor (about 21") on the inside.  The design also eliminated the need for a "duck-under" at the entry point.  The layout is designed for point-to-point operation (staging yard to staging yard) but also provides for continuous running through a couple of reverse loops, one stacked upon the other.  The minimum radius is 30", but most are larger, and the maximum grade is about 2.25% in the helix between levels.  Design elements are bound to change as the layout progresses.  

Lower Level

Upper Level

  
Actual construction will start once the weather warms up and the existing layout is removed.  In the meantime I will be working on locomotives, rolling stock and structures.