Minimum Distance?

Discussion in 'HO Scale Model Trains' started by tetters, Jan 3, 2008.

  1. tetters

    tetters Rail Spiking Fool!

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    Hi guys. After searching the threads regarding elevation and grades percentages for layout design, I still cannot wrap my head around the numbers. :oops:

    What I am looking for is the minimum distance allowable to get a 1-2% grade up to a whopping 1/2 inch elevation. I imagine it cannot be that far of a run.
  2. MasonJar

    MasonJar It's not rocket surgery

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    1% is 1 inch of rise (height) in 100 inches of run (length). 2% is 2"/100".

    Therefore, to go up 1/2" @ 1% requires 50 inches of run; @ 2%, it requires 25" of run.

    The formula is grade% = rise/run x 100. You can solve for any one part, as long as you know the other two.

    Hope that helps.

    Andrew
  3. tetters

    tetters Rail Spiking Fool!

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    Big help. Thanks Andrew!
  4. MasonJar

    MasonJar It's not rocket surgery

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    No problem. :)

    Andrew
  5. tetters

    tetters Rail Spiking Fool!

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    I just wanted to make sure I had enough room to elevate the track work behind my yard. Just to make it a tad more visible. I've got about a 2' 6" of straight run before a turnout. I'd like the elevation to occur before then. I was trying to keep it to a 2% grade at most.
  6. stuart_canada

    stuart_canada Member

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    i find if you raise it a 1/4 inch per running foot it is a nice smooth grade, but you could go 1/2 per running foot .....it is anot as smooth but it works
  7. 60103

    60103 Pooh Bah

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    You also need to put a bit of a curve at the top and bottom of the grade. Usually you can do it by fastening the roadbed down flat at both ends and letting the bit in between take a natural curve. To get you grade, you may have to allow a bit more length at each end.