Hello I am new to the site and board… how much incline would i need to take a train up a mountian of about 2-3 inches tall? my layout is on a 4x8 1/2 thick plywood table… the mountain will be adross one end… thanks for any help hobojim
Hi. This is a link to a thread where this topic was discussed. At the bottom of this page is a search facility. If you type “how to calculate grade” in it and hit enter, you will find reams of similar threads. Good hunting.
A 1% grade would raise your track 1" for every 100" of linear track. A 2% grade would go up 1" for every 50". 4% would go up 1" every 25". 4% would be about as steep as you’d probaby want to go, your engines would only be able to pull a fraction of what they could pull on a flat grade. If possible 2% or less (in real trains and models) would be preferable.
Another way to look at it. 1%=.001 per foot, or inch. As long as you keep your units, foot or inches consistent. To determine your grade between two elevations you merly divide the difference in feet OR inches by the distance.
For example it may say on a set of plans. 2.3% grade. That means .0023 per foot OR inches.because 1%=.001 So if you have a 60" straight section of track and you want to come up 1.5" then 1.5"/60"=0.025 or a 25% grade. Way too steep. 60"*0.025"=1.5". Your rising at the rate of 25/100’s of an inch per inch. As the guy (please excuse) whom I quoted says a 1% grade, using inches as units = means your coming up 1" in 100" or 1/100th of an inch per inch.
So!
To determine grade.
Difference in elevation/distance = grade as a percentage.
Grade * Distance = Rise or fall ( if your going downhill,negative grade).
Railroads, Pipelines, same thing, grades as a percentage are figured the same.
1% means .001, 2% means .002 etc, per unit of measure. A common mistake in the pipeline business was guy’s mixing up the units of measure, Feet vs Inches. Use one or the other, dont mix em up.
JulesB
Tonight I just glued down the Woodland Scenics incline starters to create a 3 inch rise. This is the easiest way to create an an incline.
You don’t have much space to get your track up, so you will need a 4 degree incline like me, unless you want to continue your incline far around each end of the loop on your layout.
A 4 degree incline set will get you up to 3 inches in 6 feet of track, and you will need another 6 feet to come down again. So you will definitely be running the incline completely along the entire length of your layout and around the curves at each end.
The same set will get you up 2 inches in only 4 feet, and another 4 feet to come down.
The most realistic gradient, 2 degrees, will require 24 feet total to rise 3 inches and come down and 16 feet of track to rise 2 inches. So that’s a bit out of the question for you. And the 3 degree set also requires more space than you have.
More than 4 degrees is not practical for locomotives.
Jules, you slipped your decimals over a spot. 1%=0.01, NOT 0.001. Makes a tiny bit of difference, only a factor of 10![:D]
Whoa, wait a minute. Better recalculate that. Lets see here:
2% (or .02) x 3 (inches of rise) = 150", (or 12’6")
2% (or .02) x 2 (inches of rise) = 100" (8’4") (definition of 2%; 2" of rise in 100" of travel)
3% x 3 (inches of rise) = 100" (8’4") (Again, definition of 3% grade)
3% x 2 (inches of rise) = 66.6" (or 5’6.6")
4% x 3 (inches of rise) = 75" (6’3")
4% x 2 (inches of rise) = 50" (4’2")
One thing that hasn’t been mentioned is that you will want to ease your grades, that is to say, you want your grades to start gently, not an abrupt change from flat to 4%. My last 3% grade had a 24" transition on either end, if I was planning a 4% grade I’d allow 12 extra inches past the end, and use that to transition from flat to 4% (you would use the first 12" of 4% grade section, as well.) You will end up with a 24" transition. You could use a 8" section of 3%, a 8" section of 2", and a 8" section of 1". I used the open grid/cookie cutter method and simply screwed my risers on the ends and end of grade to the proper height, then adjusted my intermediate riser to the height of the board. This resulted in the 24" transition.
Brad
H:
I advise you to build a few test tracks and try various grades with the equipment and trains you want to use. Also try them on your intended curve radius, combined with the intended grade.
Experiment will tell you a lot, because the rules can vary a lot depending on what you’re running.
One reason: Old-style equipment (heavy die-cast engines, weighted with lead, pulling rather poor-rolling cars) tends to have a flatter train length vs. grade curve than newer stuff (light plastic engines, weighted with zamac, pulling very free-rolling cars). The reason is that train friction also drops off as engine-wheel friction does on grades, which tends to partially offset the grade’s effect. This may well be the reason people seemed to consider 5% to be steep but manageable in 1960, but completely excessive in 2000.
An illustration of this situation:
http://www.geocities.com/joetubesock/trg.htm
Grades that drastically restrict train lengths could actually be fun if you want to simulate prototypical challenges, such as needing to double the hill or cut in helper units with a long train.
You are absolutly correct, It was late. The example I gave should have said 2.5% grade.
I’m retarded now so I haven’
I was just posting on a related thread I had started concerning Z-Scale and saw your question. And since I have just done the work, I thought I would answer your post while the math is still fresh in my mind:
Here is what I think you need:
Any track running under a layer above will have to have the following factors known:
The scale’s vertical clearance (NMRA standard) from top of rail to ceiling of tunnel (that ceiling is the bottom of your plywood roadbed holding the upper level) plus the thickness of the track from bottom of ties to top of rail; plus any cork ballast (also called “roadbed” just to make it confusing!); plus the thickness of your plywood roadbed (because since the bottom is the ceiling, you will have to climb the thickness of that ceiling to pass over it).
Because there has been some confusion on this thread, I’ll prove the math as already corrected by another:
.1 is one tenth
.01 is on hundredth (same as percent)
.001 is one thousandth
Next, most model railroads do some climbing of grade on curves. I haven’t thought through the math to calculate a grade on a curve which changes its radius as it flows (i.e., a “French curve”), but a set radius is easy.
2piradius = circumference of a circle. What part of a complete circle is your turn representing?
A climbing turn for model railroads usually is placed at the end of a rectangular layout so on which the track begins the climb in one direction and ends after turning 180 degrees to run in the opposite direction on the far side of the layout.
180 degrees is half of a circle, so you only use half of the circumference to know how long your track-run is in the climb.
3" rise at 2% grade = (3"/.02) = 150" of track length
3" rise at 3% grade = (3"/.03) = 100" of track length.
Now factor in curve.
For a 20"
Hello thanks for all the help and advice… i went with 1.5 inch at the steepest point works well with my engines and cars… if i knew how to post pictures i would…
thanks again ALL
Hobojim
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twcenterprises wrote: |
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Fawlty Logic wrote: |
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The most realistic gradient, 2 degrees, will require 24 feet total to rise 3 inches and come down and 16 feet of track to rise 2 inches. |
Whoa, wait a minute. Better recalculate that. Lets see here:
2% (or .02) x 3 (inches of rise) = 150", (or 12’6")
2% (or .02) x 2 (inches of rise) = 100" (8’4") (definition of 2%; 2" of rise in 100" of travel)
Brad, I mistyped the info…of course it is just as I said, but …12 feet plus 12 feet = 24 feet for a complete rise and decline at 3% …and 8 + 8 feet = 16 feet for a complete rise and decline of 2%. (the diagrams at Wooland Scenics wouldn’t lie…and I am looking at some in my hand right now.
Anyway it’s best to forget all the math calculations given above and just buy the Woodland Scenics risers unless you want to start building up your own inclines with messy amounts of DIY foam, cardboard and plaster. Just put down the risers and laysome plaster cloth around the slopes. Works like a charm in much less time than going mental with math. And you can mix and match the pieces to vary the incline and create level spaces anywhere.
I greatly recommend it over the brain puzzle techniques above.
Just so you know, Woodland Scenics Grade pieces aren’t exactly the grade listed. I.E. A 2% incline will go up 4" in 16 linear feet, that is 1" per 4 feet, or 1" per 48", a TRUE 2% grade would be 1" in 50", now 1/50=0.02 or a 2% grade, but 1/48=0.02083333333333333 or about a 2.1% grade, so it’s close, but not exact, and the difference is too little for pretty much anyone to cry over. Let’s try the 4% it has a slope of 4" in 8’ or 96", this
To make it a little simpler, let’s utilize a little fuzzy math, round off 96 inches (8 feet) to 100 inches. To get get 1 inch rise in 8 ft is just a hair under 1% grade, or 1/4 inch in every 2 ft. Each additional percent in grade would equal approximately another 1/4 inch in every 2 ft, so a 2% rise would be 1/2 inch in 2 ft, 3% would be 3/4 inch in 2 ft. On a curve, simple math will give you the run length so you can plan how far back you have to start to get your desired height, using the fomula for circumference of a circle (2 pi. r) or 6.28 times the radius of your curve. for example, a 22" radius would (roughly) require 22 x 6.28 (138.16) inches for a complete circle, about 34 1/2 inches per quarter turn (90 degrees)
For planning purposes, 3% grade, 22 inch rad. 1/2 circle will use abt. 6 feet of track, resulting in a grade increase of (3/4 " x 3 (2 foot) sections = 2 1/4" An 18 inch rad = abt 56" of track, resulting in abt 1 3/4 " grade increase in a 1/2 circle
Just estimating in my head ( someone else can do the actual math ) this will result in abt an actual 3.1% grade which should be about the max. anyone would want to model on main line trackage.
I hope these figures help
I’ve been raising my inclines 1/2" every 2’ and Don’t seem to be having any problems at this stage.
God bless,Alan
To get away from the math for a minute and give you some other perspective I’ve got a 4x8 connected to a 44"x60" in an L shaped layout. I wanted a mine on top of the smaller section that was going to be 6" higher than the mainline. To reach 6" I had to have at least a 3.1% grade that runs about 15’. I really like elevation on a layout, but because of small space like we’re doing you have to be a little inventive about how you do this. I solved a lot of my problems by posting my layout plan and asking for advice. One of the best things I ever did. 
Good luck, we’ll be interested in seeing some Pix.
Good advice to others.
On smaller layouts, steeper grades are inevitible. For logging and mining even grades pushing greater than 4% can even add to operations. Since you can’t run trains or store a dozen hoppers the max amount needed can be broken up and done in sections. Of coarse 1-2 hoppers at a time would be a bit rediculous so testing for max grades is in order.
Just as a further note. Last week I powered up the new layout and drove some locos around, including up and down the 4 degree incline I created over a spur to a yard. I am fairly well pleased, even thought the incline is not realistic.
But, didn’t hook up any freight cars yet.
All locos took the hill well,…6 axles, 4 axles, (these diesels will never have a problem) 44 tonner, 70-ton shay, all steamers…except…you should see the P2K 2-8-8-2 spin away. Just for fun I am going to MU it with a matching 2-8-8-2 when I get the decoder in, just to see if two slip more wildly or help each other.
But obviously a steamer without rubber tires, lots of weight and unrealistic drive power makes a 4 degree grade look even more stupid.
email me offline at kk4ej@yahoo.com and I will send you a free excel chart to use for grades.
Makes grade figuring very easy…
Randy
kk4ej@yahoo.com