8 feet length on a 4 inch rise will give you about a 2 percent grade,
which would be my recommendation. The formula you use to determine the
percent of grade is: one quarter inch rise for every 1 foot of length
equals about 1 percent grade.
"Who do you serve.... And who do you trust?"
(To e-mail me, remove the X from my address)
At a grade of 1%, that would be 100*100mm or 10,000mm [1,000cm, 10m]
(or 100*4in or 400 inches [33-1/3 feet]). 1% is fairly slight. At 2%,
it would be 50*100mm or 5,000mm [500cm, 5m] (or 50*4in or 200 inches
[16-2/3 feet]). 2% is beginning to get 'steep' for many locos pulling
trains of non-trivial size. Note: grades are effectively *worse* on
curves: a grade on a curve 'behaves' (in terms on traction / power
needed) as if it was steeper than the same grade on a straight section,
so the grade on a spiral would have to be more gentle. A 36" radius
circle has a circumfrence of 226.19448", so once around at 1% is a rise
of 2.2619". This is *barely* enough to 'stack' trackage (unless you are
running double stacks or Superliners (double deck passenger cars)).
Separating 1/2 circles by 4' inproves things:
1st 1/2 circle (36" radius) @ 1%: 1.1309" rise
1st 4' straight @ 2%: 0.9600" rise (2.0909" cumulative)
2nd 1/2 circle (36" radius) @ 1%: 1.1309" rise (3.2218" cumulative)
2nd 4' straight @ 2%: 0.9600" rise (4.1818" cumulative)
Robert Heller -- 978-544-6933
Deepwoods Software -- Download the Model Railroad System
Why the hell should we do that?
I actually take offense at your suggestion: some of us (a *lot* of us,
including lots of folks in the UK, a supposedly metric country) actually
prefer our antiquated, flawed systems of measurement.
Personally, I like Vista, but I probably won't use it. I like it
because it generates considerable business for me in consulting and
Actually all that you've really shown is that decimal is great for
calculating percentages. I can do 2%, i.e. 2/100 of an foot per foot
on my engineering ruler just as easily as you can do 2 cm/meter.
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