A Discusson on Double Decked Layouts

Maximizing the amount of model railway layout in a room's set square footage is an age old problem that all model railroaders face.  Since we are confined within the walls of the room, there is only one, well two places to go...Up or Down.  So, the big question arises.  Do you double deck your layout?  And if you do, will the loss of space for a helix and the inevitable boredom of running a train in a helix make up for the gain in model railway landscape?  Are there other ways to gain the same elevation but avoid a helix?  How can I make this layout as big as possible and still be pleasing?!   Like everyone else, I struggled with these question with my layout.  This article is about how I handled the situation....

Preamble

Illustrating Elevations

First, let me say I don't like double decked layouts.  I'm 5' 7" tall and most of the double decked layouts I've seen are either too low or too high.  Usually the latter.  I really like model railways with lots of scenery and most of the double and especially the triple deckers I've seen were built for operations.  It was obvious that the often too tight deck separations had no planning for scenery.  I'm sure those layouts are still not sceniced.  To each his own I guess.

Lower Level Trackplan

All that said, my current layout is of the Rio Grande Southern's first district and from day one I had planned on modeling a 26ft long version of the Ophir Loop. The real Ophir Loop was designed to increase elevation over Lizard Head Pass. That presents some big problems in model form. My version of the loop with its prototypical 3.5% grade creates a grade separation of 18" by the time it loops back and forth along the wall. What could I do? Reduce the grade? Put in a Helix (Yuk!)?

Upper Level Trackplan

Have two tracks running through each scene so that I can run the grade down? I didn't like any of those ideas so I ended up giving in and double decking part of the layout. I decided that I'd turn this negative into a positive and add a lot of run time to my mainline. I put towns on the upper level that wouldn't require a whole lot of switching, but would add distance and operational interest. Trout Lake is over Vance and Vanadium. Lizard Head is over Placerville.

Grade Separation

The 18" rise from the Ophir Loop was enough gain in elevation to start the double deck part of the layout over Vance Jct. However, another problem caused by sticking to the prototype grade was that my loop around Trout Lake was doing the same thing as the prototype; gaining elevation! Keeping to the prototype grade would have brought the track about 6" below the floor joists when it reached its apex at Lizard Head.

Raised Floor

Taking a slightly less severe grade (~2%) as far as trestle 51-A kept a nice benchwork separation and the look that I wanted. The track levels out at 51-A until just before Lizard Head and then rises again to get a nice peak in the track on the mountain pass. The constant rise in elevation to Lizard Head created a new problem. The track peaks out at 70" above the floor and I don't have enough train room left to bring the grade down to match the lower level. The answer turned out to be building a raised floor at Rico. Since I can't bring the track down, I might as well bring the operators and visitors up.

Admittedly, the upper deck is a little tough to see in places. I tried to counteract that by making the scenery slope towards the front of the layout. I think this helps the shorter visitors to see and creates that "looking up at a train on the edge of the mountain effect". Think of windy point on the C&TS.

Benchwork

Cantilevered benchwork

I had decided that to build a double decked layout correctly, I absolutely could not have support posts at the front of the scenes. Building the benchwork proved to be an exercise in amateur engineering. What I ended up doing was using metal shelf brackets for the narrow sections of the layout. However, Lizard Head is deep at almost 4ft at the wye so shelf brackets were ruled out. What I ended up doing was cantilevering the benchwork by integrating it with Rico's benchwork. Rico is right behind Lizard Head on a peninsula so I created a "wall" between the two and used 1x4 supports that stick out each side of the wall equally. Think of a "T" shape. The benchwork on each side was built around the arms of the "T".

I've seen some double decked layouts where the benchwork is unnecessarily tall. For HOn3, I only need minimal support and only enough height in the benchwork to hide the wires and lighting. I'm a big fan of open grid benchwork built with 1x4s. My standard benchwork kept the height of the benchwork to the width of a 1x4. I could have gone thinner with 1 x 3s or metal but that would have just caused problems with hiding the light fixtures.

The Tunnel Effect

One of the major goals of this layout was to make the aisles wide and comfortable for visitors and operators. There is no compromising on this. Double decking an 26ft long aisle would create a tunnel and seemed counter productive. What I ended up doing was stepping back the upper deck on the Trout Lake side. I only needed enough width for a siding and some scenery. There are places where the lower level is up to 40" deep while the upper level is only 12" deep. That seems to have solved the tunnel effect problem but complicated the lighting. Both levels of the Lizard Head/Placerville side are the same width.

Stepped back at Vance

Stepped back at Vanadium

Stepped back at Old Placerville

No Step at Placerville

Slight Step at Ridgway

Lighting

Recessed light fixture

My layout is lit with 34 fluorescent tubes and a few fluorescent bulbs. To hide the fixtures in the upper deck benchwork, I created segments of 5ft long open grid benchwork with 50" wells in the middle of them. I mounted the fixtures so that the tubes face downward in the wells.  That ended up recessing them enough to be hidden.

Where it wasn't practical to fit a 4ft tube, I mounted a standard screw-in light receptacle and used a "daylight" fluorescent bulb. That seems to have worked but has created a minor colour balance problem. I'm running GE Chroma 50 equivalents (5500K / high colour replication) for all the tubes.

My stepped benchwork created a slight lighting problem for the lower level which I don't have a solution for. Because the fluorescent tube is inside the upper level benchwork, it is placed far back and behind most of the best scenery on the lower level. This makes the front of the structures and trains a little dark since they are in shadow. The large volume of overall room lighting seems to help eliminate shadows, but isn't a perfect solution. I guess that if it ever becomes a major problem I can add spot lights above the aisle that point down on the front of the scenes. I'd hate to do that since it will create heat and I'm already running around 1500 watts of lighting.

Elevations

The following lists the elevations to give you an idea of how it all turned out. For the most part, it works for my height and the majority of my visitors. Most of my operators are around the same height as me. The only real issue is at Lizard Head which is a little high for most people.

Town/Location	Track Elevation
Placerville	42"
Vanadium	40.5"
Vance Junction	43"
Ophir	52"
Upper / Lower Deck Transition	61"
Trout Lake	65"
Bridge 51-A	68"
Lizard Head	70"
Rico (raised floor)	51.5"
Rico (basement floor)	67.5"

  The amount of space between levels (lower track to underside of upper benchwork) ranges between 13" and 18". Those height allow plenty of room for scenery and a comfortable working space. Sloping the lower level scenery down at the front of the layout makes it feel more open, too.

Step Stools

Step Stool

To help see and operate Lizard Head I had my father build some step stools based on an article in Model Railroader magazine. (March 1999, Workshop, page 34.) I customized the height of the stools to work better with my layout.

Conclusions

I don't have any regrets about going double decked now. It adds a lot of run time to my operations. We often double the hill and there is about 100ft of mainline between Vance and Lizard Head so that makes for some long runs. I managed to avoid a helix and keep the scenes separated. The aisles feel comfortable and there is plenty of room for my operators. I have a few minor lighting issues at Vance and Lizard Head is a bit too high, but the benefits outweigh those compromises. I'm satisfied with what I have...

Craig Symington - Sept 2006.