Track Grade ?

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J

JoeG

New to N scale
What do you think about a 3% grade? I dont have alot of room and i need to get the track up to 2'' in 5'. I figured that if I need to I'll be able to place a few Loco's on for added power. I wont be running to much more than 15 cars at a time.
 
you should be fine if all you pull is about 15 cars. just make sure they have proper weight and metal wheels. as I type this Im wathing my Broadway heavy mike pull 17- 40' freight cars up my 3% grade in a 22" radius without slipping(no traction tires) if i get near 20 cars it will struggel sometimes. I think the curve helps traction to be honest as it is banked and I think the locos "dig in" on the curve?


I did it for the same reason as you. needed space to get the mainline up and over itself
 


You're running a little over 3% at those specs and it will probably be even more when you consider your easment into the grade. The easement is the gradual change of grade from level to incline so the couplers don't come apart. For a 3% grade, I think you would need about 5' just to get into the grade of 3%. You will more than likely end up with a grade much steeper than 3% with your restrictions.
 
The general warning/idea in the previous post is worth noting, as it is correct. You will need transitions on either end of the distance you have alloted to the elevation change. Necessarily, what lies between those transitions will have to "make up" the elevation change that was taken up in the length where the transitions rise to something close to the intended grade, and then drop back to level again at the high end. That means steeper, perhaps as much as a full 0.5%! :eek:

I do quibble over the length suggested for a transtion, even for a 3% grade. If ever a transition into a steep grade of 3% (which happens to be my own case) were needed, it would be for long driver-based steamers. I have several Northern type and Texas type engines that don't seem to mind my transitions that are in the 16" range...only.

No matter what any of us says, it is incumbent upon the user to establish for himself what will work, as a minimum, for his own purposes. That means doing trials with the engines and typical cars/lengths of consists that he intends to use. Once he gets reliable negotiation of curves and grades, in both directions of travel, and running in forward as well as reversing, he then has established what is likely to work on his own layout, providing he duplicates that minimum or improves on it.

-Crandell
 
2 3 & 4 percent grade

OK I think this is right.

2% would go 0 to 2" in 8ft oneway

3% would go 0 to 2 1/4" in 6ft oneway

4% would go 0 to 2" in 4ft oneway

NYC_George
 


Grade calculations are the same irrespective of the scale. A grade is a grade is a grade... How you calculate a grade is as follows, and once again, it works for all scales, all the way up to your back yard scale: first, take the number of units of height. You want a clearance of 3"? Then inches is your unit of measure. Now you find out how many inches of travel you need to achieve your clearance. You may find that your plan calls for 7'. You must deal with inches, though, since inches is what the first dimension, the height, was measured in. Seven feet times 12" per foot equals 84". So you need 3" of height and you have 84" to achieve it. We'll forget about the transitions curves from level to full grade. The formula for a grade, regarless of scale remember, is "rise over run". Your rise is the 3", your run the 84". Rise over run, mathematically is expressed as 3/84 in this case, or "three divided by 84". If you are weak in long division, use a caculator. Enter "3", hit the divide button, and enter "84". Press "=" button. You get a displayed value in the readout of "0.03571428.....etc". Just pay attention to the first three whole numbers, the "357". It is to be read, for our purposes, as "three point five seven" percent, or just a hair over 3.5%.

How steep is that? Very. But you may be stuck with it if your space is tight and you are also stuck on a plan calling for that rise in that space. Just be aware that your engines will work hard to get a train of any length up that grade.

The worse news is that you must ease into and out of that grade. Your engines won't be able to keep moving going from level track to even a 1.5% grade if it is abrupt. You must curve slowly up to the grade, and that takes space...on each end! :eek: You can see that the middle portion of the grade must be even steeper than 3.5% in order to get the 3" clearance you said you needed. Even harder pulling for that poor engine.

Of course, you can double engines if you need to and if you have two that will work well together.
 
well I just went and checked my grade

just for refrence with my previous post i went and checked both my grades

I have a 3" rise and 105" run
3 / 105 X 100 = a 2.85 grade

my other grade is 1.5 rise and 54" run
1.5 / 54 X 100 = 2.77 grade

both are in a 22" radius and all my locos can pull up the grades with at least 18 cars this is in HO scale. If I recall N scale has more troubles with grades so use caution, Us HO guys can get away with slightly steeper hills.
 
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