# elevated roadbed in a circular shape



## mymodeltrain (May 14, 2013)

This is just curious since I am not going to build a new railway soon. I saw some railways have an 8-shape in which one track is a foot above the other when they cross. In that construct, it means they have to build a graded circle in one end of that 8-shape track. My question is that anybody has a video showing how to build a roadbed with an elevated track in a circular shape.


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## Pete Thornton (Jan 2, 2008)

> video showing how to build a roadbed with an elevated track


I googled "video showing how to build a roadbed with an elevated track" and got several YouTube videos.


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## mymodeltrain (May 14, 2013)

Pete Thornton said:


> I googled "video showing how to build a roadbed with an elevated track" and got several YouTube videos.


Pete,
I see the same but all are for N scale. I want to learn how to do that for G scale.


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## Greg Elmassian (Jan 3, 2008)

Are you just asking construction techniques for an elevated layout?

Greg


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## mymodeltrain (May 14, 2013)

Greg Elmassian said:


> Are you just asking construction techniques for an elevated layout?
> 
> Greg


Yes, I am asking for the techniques how to make a graded roadbed. I see this movie and I want to do like this in the future, 



.


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## Garratt (Sep 15, 2012)

It just depends on one's preferred construction. Some do it straight in the gravel, others make a concrete base or use the 'ladder' construction technique which can be done various ways with wood or plastic materials that don't rot. The ladder base will determine a consistent grade and can sit on wood or PVC posts. There is math and elevation checks involved for anything curved that can't be done with a string line.
I think you need to refer to more than just one forum discussion or video to determine a method. Different strokes for different blokes.

Andrew


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## mymodeltrain (May 14, 2013)

Garratt said:


> It just depends on one's preferred construction. Some do it straight in the gravel, others make a concrete base or use the 'ladder' construction technique which can be done various ways with wood or plastic materials that don't rot. The ladder base will determine a consistent grade and can sit on wood or PVC posts. There is math and elevation checks involved for anything curved that can't be done with a string line.
> I think you need to refer to more than just one forum discussion or video to determine a method. Different strokes for different blokes.
> 
> Andrew


Thanks for the information; it's exactly what I need to know; but I have to agree that it is not simple. I just read one chapter of a book written by Jack Verducci, in which he explained pretty well; for example to calculate the grade of a curve, he took the desired elevated height / circumference of the curve. And the circumference = Pi x diameter.


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## Garratt (Sep 15, 2012)

The maths is fairly straight forward but one thing to perhaps to watch out for is if you use the ladder system the curved grade is actually a helix, so if you make a flat curved ladder on the ground first then attempt to elevate it you may end up with the track tilting from side to side. Probably wouldn't be a problem on broad curves because things can twist easier to where it should be. 

Some things to consider:

Minimal grades to save wear and tear on locomotives and to help stop them running away down hill.
Transitioning into curves and grades. 
Sidings need to be level for parked cars.
Invasive plant roots along the right of way that can disturb the road bed.
Large tree roots that can lift concrete sections over time.
Effects of frost heave in your area.
Possible damage by visiting critters.
Water drainage and possible erosion in deluge.
How the track is secured and the effect of rail expansion and contraction in hot and cold weather.
The ability and ease to repair track alignments and grades.
The use of materials that may rot or degrade.
Whether you want to move large amounts of soil or use a hedging plant for 'embankments'.
How permanent are the works to be within the garden.
Accessibility to all parts of the railroad.
Electrical implications and wiring conduits.

Andrew


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## Homo Habilis (Jul 29, 2011)

Could posting these two pages constitute a Copyright infringement?


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## mymodeltrain (May 14, 2013)

**** Habilis said:


> Could posting these two pages constitute a Copyright infringement?


Have no idea, I am not a patent lawyer; this is from a book that I have and I didn't sell the information for benefit. So for the safe side, I delete those pages.


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## Garratt (Sep 15, 2012)

Half the Internet is a Copyright infringement but I thought the same. The publisher of the intellectual property is potentially losing sales if someone else re-distributes it in whole or only a part of it to the general public. It's only fair on him to not do it for such a niche market.

Andrew


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## fyrekop (Sep 20, 2011)

A suggestion regarding checking that grade. Sears, Lowe's etc sell a digital level that can be setup to provide percentage of grade readings. I used a 36" model when building my trestle. It spanned 3 bents, even on the 10' Diameter curves, as I put bents in place and resulted in the 1.5% grade I was trying for.


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