Any suggestions for HO gradient?

Can anyone suggest the minimum length required to meet a rise of 100mm or 4 inches in HO scale.
Any help is greatly appreciated.

Scuzzie wrote:
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with what sort of motive power and what length/weight of trains?

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Thanks for the reply . . . nothing special in terms of power, just an average Hornby or similar and 4 - 5 passenger cars or 10 - 15 goods wagons
thanks

Scuzzie wrote:
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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.
Fred Ellis

Fred Ellis wrote:
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That's about a 4% grade, Fred: 8ft = 96 inches. Etc. Too steep.
But you're right to recoemmend a 2% grade (or less).
Cheers,
wolf k.

Wolf K wrote:
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Wolf, thanks for the correction. I thought I had made a miscalculation. I should of wrote "16 feet of length on a 4 inch rise will give you about a 2 percent grade."
Fred Ellis

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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)
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On Fri, 20 Feb 2009 08:38:26 -0600, Robert Heller
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On Fri, 20 Feb 2009 17:07:01 -0600, Scuzzie wrote:
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It would be of great help if you accepted the metric system. Then that 2%, which is what I also use as a maximum, translates into 2 cm rise per meter. Or 2 m per 100 m. It can be so simple..

On 2/21/2009 12:44 PM Wim van Bemmel spake thus:
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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.
Hmmmph.

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Luddite! :-)
-- Cheers.
Roger T. See the GER at: - http://www.islandnet.com/~rogertra /

Roger T. wrote:
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Nah, just a guy who knows the difference between a logical system and a useful one.
;-)

I finally get back my USENET and get met with this nonsense!
-- Bob May
rmay at nethere.com http: slash /nav.to slash bobmay http: slash /bobmay dot astronomy.net

Bob May wrote:
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We haven't had that much utter nonsense for a very long time.
How long have you been away?

There! Now at least the title matches the subject :-).

Bob May wrote:
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Hey, Bob, welcome back!
And how dull Usenet would be without some nonsense once in a while? ;-)
Cheers!
wolf k.

On Sat, 21 Feb 2009 23:40:02 -0800, David Nebenzahl wrote:
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Be happy with it.

On 2/22/2009 4:00 AM Wim van Bemmel spake thus:
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Oh, gawd save us from the Eurocrats ...

wrote:
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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.
Jim

On Sun, 22 Feb 2009 13:45:42 -0600, Jim wrote:
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Except that I don't need an engineering calculator or ruler for that ;-)