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I want to make a loop in order to get a multi level arrangement to add interest and switch fun. This will be indoors (above garage) so I have a limited space issue of 12 wide by 16, but I plan to cut into the side walls and create tunnels in the attic on each side which will give me a little more in the 12 dimension. Naturally, I will close off and insulate the tunnel portions in the attic but leave access in the event I have to mess with it. I will be running the Bachmann Spectrum Shay, Climax, and 4-4-0 for now but will probably add others.

So my questions are what kind of grade can I have? I have heard the number of 3% but what can this be stretched to? Next, if I have a track crossing under another, what type of clearance would you suggest. The Shay looks like I can get away with 9" but what should I shoot for? I will probably have to create a loop as part of this getting height, so how tight of a curve should I shoot for when making this climb? ANY INSIGHTS WOULD BE GREATLY APPRECIATED. Has anyone done this before and can you post any pics?


Only two things more fun than the planning stage; the building and the playing stages.
 

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The locomotives you currently have will do fine with a 4% grade (that is the max I have personally seen them use). So, to better help you with grades, what cars are the locomotive expected to pull? Are they logging disconnects or heavyweights? The amount of cars as well as the weight of the cars will affect how much grade you can have.
 

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So, at 4%, you can rise about 4 inches in 100. 100 inches is 8 ft 4 inches. To get a 12 inch rise for a track to pass over another, you'll need 25 ft to get up, and another 25 ft to get back down.
 

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My layout is indoors also, at 10"W x 19'6"L and averages about 4'D and manages a 10" crossover in about 16' of run, about a 4-1/2 to 5 % grade, steep but do-able. Your Shay and Climax will take such grades but I suspect your 4-4-0 American will suffer greatly. Also indoor space you describe could limit your curve radius's. I opted for using the smallest diameters 4' so I could maximize the track plan, all it meant to me is that I cannot run any of the larger newer locomotives and cars on the market today. Big Deal IHO, as it is I have a huge roster of interesting loco's and cars that all run just fine on the smaller curves. Again your Shay and Climax will take the 4' diameters, even with the 5% grade, OK but not yourAmerican, it needs 5' or wider, much wider on a grade.

Planning in the early stages is paramount to avoid problems when you begin construction. You need to determine what your goal is, what space you have, how best to view that space, how best to provide viewer and maintanence access that space, then how best to insert construction into that space. Building indoors is challenging in large scale, but its also ALOT of fun.

What is your goal?

Fun-n-run?

Finescale logging layout?

 

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Discussion Starter #5
Any pics so I can get some real word ideas.


Mickey



Posted By vsmith on 01/29/2009 10:27 AM


My layout is indoors also, at 10"W x 19'6"L and averages about 4'D and manages a 10" crossover in about 16' of run, about a 4-1/2 to 5 % grade, steep but do-able. Your Shay and Climax will take such grades but I suspect your 4-4-0 American will suffer greatly. Also indoor space you describe could limit your curve radius's. I opted for using the smallest diameters 4' so I could maximize the track plan, all it meant to me is that I cannot run any of the larger newer locomotives and cars on the market today. Big Deal IHO, as it is I have a huge roster of interesting loco's and cars that all run just fine on the smaller curves. Again your Shay and Climax will take the 4' diameters, even with the 5% grade, OK but not yourAmerican, it needs 5' or wider, much wider on a grade.

Planning in the early stages is paramount to avoid problems when you begin construction. You need to determine what your goal is, what space you have, how best to view that space, how best to provide viewer and maintanence access that space, then how best to insert construction into that space. Building indoors is challenging in large scale, but its also ALOT of fun.

What is your goal?

Fun-n-run?

Finescale logging layout?

 

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Make sure you have plenty of clearance in the tunnels for height and width as the shay is tall. Make sure you measure with loco sitting on rail. Later RJD
 

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R2 (Five foot diameter) curves are about as tight as I would care to go. One full R2 loop plus three or four sections of straight track can make for a doable climbing loop, but to get to that second level, your going to need at least two such loops, and two and a half would be better, as you would want at least twenty inches (and preferably two feet or a bit more) between the top of the bottom level and the bottom of the top level. Otherwise, you get into issues with structures and scenery that might not fit all that well. You might want to look into sort of 'stacking' the loops atop each other, making a sort of quasi Helix, which is on the agenda for my own indoor line...eventually.
 

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Posted By mickey on 01/29/2009 1:46 PM
Any pics so I can get some real word ideas.


Mickey























 

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Mickey,

Make the curves as large of a diameter as you can and still achieve your operating goals. The trains will look better, probably will operate better, and will give you flexibility over time. I agree with Snoq Pass that 4% is a good target maximum, but if you are willing to use just geared engines, you could probably go for more. I use 9.5" for vertical clearance, which works out to a little over 10" with roadbed and benchwork figured in. That is enough for many of the 1:20.3 engines, but will not clear the big ones like K-28 and K-36. Tight curves on grades will further limit your engine's hauling capacity, just like on the prototype.

A couple of other things to consider is the sideways clearances and vertical curves. With small radius curves, cars and engines can overhang the track a good bit so be sure to leave enough sideways clearances, both inside and outside the curve. The other is the vertical curve, the transition from level track to the track on a grade. This is particularly important if your grades are steep. The transition should be as gradual as possible. A steep transition curve will result in pieces of the rolling stock, like pilots, getting hung up, or cars uncoupling. This space taken by the transition curve will effectively increase the slope of the grade between them.

The photos on my web site are a bit dated but it will give you an idea of how I approached it. http://1stclass.mylargescale.com/MikeO/index.html

Mike
 

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Don't forget that wheels on curves have more friction than on straight track. So, a sharp curve in the middle of a steep grade means even shorter trains, and puts additional strain on the engine.

You could add a powered tender to your 4-4-0, which would be cheating, but would ease the strain on the main motor and gears. An engine like this would probably only have pulled one or two cars on a 4% grade anyway.

We always associate logging with geared engines, but loggers used whatever was cheap. Meaning that a lot of high-drivered 4-4-0s ended up pulling log cars.
 
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