On my current layout, I have no graidents whatsoever. The layout is a P-shaped 42’x25’ and it is flat, a fictional Chicago-area railroad, entirely contructed on a 1/2 inch plywood surface supported by 2"x4" legs, 36 inches high…
I started thinking about building a staging area under the layout which would be accessed by turnouts off the main line which would gradually drop below the surface of my existing layout, enter and exit the staging area under the layout, then rise again to the surface of the layout and rejoin the main line via turnouts. But, when I think about the advisability of limiting the gradient to 2% or 3%, I am not sure that I have enough spare space to accomplish this without some sort of helix.
Am I not thinking this through sufficiently? How far down from the surface of the layout do I need to go to construct a staging area?
Cripes, I have overcome so many obstacles and mastered so many techniques in the course of building 3 layouts over the last 10 years, but each layout has been entirely flat. I don’t know what I can do in this instance.
With the run space you have a helix is not a requirement, 2% is 2 inches per every 100 so is you started in one corner and went to the other (say about 60ft) would have a 15 inch drop (more or less).
The distance is what you are comfortable with for access (it is staging after all which is generally hidden. I’m going to work with about 8 inches on my planned layout, with access very close to the aisles.
To get the best results from elevations, you want to keep the grade as low as possible, especially for staging. A long train that runs fine on the level portion of the layout could have difficulties getting up the grade from staging.
Another consideration is the present height of your layout. Using Doc’s example your staging would be about 15" below the upper level of your layout, but it would also be only 21" off the floor! You’d have to work the staging area while on your knees. You can reduce the grade to 1% (much better for your longer trains) leaving your staging about 8" below the layout and 28" +/- from the floor. You’ll have to decide if 8" is enough clearance to reach the back of your staging without interference.
I suspect that raising your existing height would be difficult. Many modelers now want their layouts at 48-50" high for more realistic viewing. If you could raise your layout 1 foot, then your staging would be about at the old level of the layout and much easier to work with.
14.4" to be exact, which assuming a table thickness of 5" will leave you with 9.4" minus the track and roadbed thickness. Approx 9" of total clearance.
Next: If you need higher legs, you can always purchase a sufficient quantity of new 2’x4’s, cut to the higher length you need, and replace them with some layout-lifting help from a number of your friends, and by using each new leg as temporary support (until immediately attached) with “friends”-ly help (unless the layout is irrevocably wall-anchored). Stooping down to apx. 18" - 24" for staging will quickly become quite tedious.
42 feet x 25 feet and not enough room? with that much room you should be able to get enough run length for anything even less than 2%. What is it like to have a run of 42 feet, that’s almost incomprehensible.
Which ever approach you decide to take on this, can I make a sugestion that you make enough room to be able to add or remove cars and or locomotive from your staging tracks without hitting the benchwork above. and not to mention those rear and for no reason derailments that always happen when visitors are present. also you need to make room for getting at switch machines and wiring without knocking things over.
sounds like you have lots of room to play with you lucky man. haha
I have enough room, just not enough spare room. I am not complaining because I have been able to accomplish so much with the room I do have in constructing a 42x25 layout. But, it is P-shaped and I wanted to construct a staging area under the portion of the layout where it curves a lot, not under the straight portion.
The responses have been helpful in two ways. One, I misunderstood the gradient concept, thinking that I was limited to 2 inches per 100 feet - - duh. At 2 inches per 100 inches, that provides a lot more flexibility. Still, to clear the layout surface and supports, I need about 6 1/2 inches of clearance so I need a 33 foot length to get down that far. Two, even if I can get down that far, as others have pointed out, that is still going to make it awkward to access the staging area, so I am going to scratch that idea.
Thanks to everyone for their responses though. It really helps to get thoughts and advice from others who have been through the process.
if you would like to get under the layout for storage, then go along the outer perimeter at a 2% grade, until it is possible to get underneath, then enter a 36 inch radius helix. Go down a foot or three spirals and enter the storage area. This way you would have enough head room to easily access the rolling stock.
Or, add another couple of spiral to further go down for easier access. Just remember that a lot of friction is created in curves, so the larger the radius the better.