# how to figure elevation question.....

Discussion in 'FAQs' started by trainsteve2435, Mar 16, 2005.

1. ### trainsteve2435Member

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hello everyone, can someone explain to me the simpleist way to figure out elevation? i know you divide something into the amount of elevation, but im confused as to how the operation goes. any help is appreciated. thanks!
2. ### TomPMAnother Fried Egg Fan

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Steve

Are you referring to percent of grade?

If so then you take the change in elevation and divide it by the horizonal distance and multipy it by 100.

In math terms it is:

(rise/run)*100

For example a one foot change in elevation over 100 feet is 1.0%
3. ### trainsteve2435Member

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Thanks Tom, thats what i was wondering!:thumb:
4. ### trainsteve2435Member

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ok guys, im haveing trouble. never been any good in math.... i have 5" of rise in 12', can someone show me how to set this up? thanks!
5. ### nachomanGuest

I just taught my class this last week. In order to get the grade in percent, you need to have the same units in both vertical distance and horizonatal distance. So, you have 5" vertical and 12' horizontal. Convert the 12' to inches - 12ft x 12in/ft = 144 in. Divide 5"/144" = 0.035 x 100 = 3.5%. Get it?

kevin
6. ### HunkiedooMember

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Here's the easy way to construct track roadbed grades (I assume that's what you wanted to know for)

1: Design all your layout grades to be 2%. (I say this only partly tongue-in-cheek; 2% is a good layout compromise grade).
2: Tape a 1/4" thick shim to the bottom of a two-foot long carpenters level.
3: Put the level on the roadbed that you want to set to grade, with the shim end resting on the "downhill", lower, end of the roadbed.
4: Adjust the roadbed until the bubble is level. You're done! No math!

(The logic is that there are 48 "quarter-inches" in two feet. One quarter-inch rise in 48 of 'em is equal to 2-in-96, or darn close to 2%).
7. ### ezdaysOut AZ way

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Just one thing to do before you do step one: be sure your layout is level... (also tongue-in-cheek)
8. ### Doc HollidayMember

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Maybe I learned "new" math, but 0.25"/24" = 0.0104 = 1.04%, not 2%

Doc

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