2% grade

Discussion in 'N / Z Scale Model Trains' started by nolink5750, Oct 14, 2007.

  1. nolink5750

    nolink5750 Member

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    Hey guys, before I do this I want to make sure I am doing my math right. I need to drop 1" "real life". At a 2% grade I calc. that would be 600' scale or 3.75" "real life". Or at a 1 1/2% grade I calc. that to be 800' scale or 5' "real". Is there a easy formula for this or am I correct in the way I am figuring this? Thanks................
  2. ezdays

    ezdays Out AZ way

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    At 2% you will drop 2" every 100", or if you want to drop only 1", that comes to 50", or 4' 2". 1.5% grade would mean 1.5" per 100", or 66.67" for 1". No need to find what that means in the full-scale world unless you're curious, if so, just multiply the results by 160.
  3. 60103

    60103 Pooh Bah

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    If you're planning to have one track cross over another, remember that the clearance has to be measured from railtop to the bottom of whatever is going over, but the grade has to be measured from railtop to railtop.
    Don is right on the arithmetic -- converting to scale feet then back again involves multiplying by a number and then dividing by it again. You have better things to do with your life.
  4. nolink5750

    nolink5750 Member

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    So scale don't matter? 2" per 100" = 2% grade in N gauge or HO or O?
  5. Gary S.

    Gary S. Senior Member

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    Nolink, you are correct. Scale does not matter. Reason why is this: Percent grade is the ratio of rise to run, in other words, it is the height gained divided by the length to obtain the gain. Therefore, units and scale do not matter because the unit or the scale is in both the numerator and denominator of the fraction and therefore cancels out.
  6. nolink5750

    nolink5750 Member

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    Thanks guys, this makes things easier. I kept X and / by 160 to figure this all out. Much easier knowing this. :thumb: