# GRADES



## paulrail (May 22, 2016)

I have been perusing this forum and love all the info I've learned!
This is why I am invoking your help again 

I plan to have a grade on my layout between 2-3 percent. The grade that will lead to staging will be at least a 4%. Steeper than would be ideal but space is limited. 

I plan to have trains about 10 cars long. My question is; Is this feasible?

I have only one engine so far, a BLI SW-1500. Will this engine pull it off? Well, the switcher may not have to pull 10 cars but what about the other engines I buy? Are some engines known for more pulling power than others? If so do I need them or should most be able to do this job? ...Or should I start modifying my plan?

Thanks!
Paul


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## bluenavigator (Aug 30, 2015)

The question is the size of the layout. How big would it be? 4' x 8'? 12' x 18' L table? Need to know more than just "2-3 percentage." Normally, we would want them to be between 1 to 2 percentage grade. No more than that. It is true that it is possible to have it as high as 3 percentage but will be limited to specific locos for pulling capacity. 

I would recommend to do the grade test first to determine the pulling power vs grade. On graded curves, the pulling power would be dropped, comparing to the graded straight tracks.


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## MtRR75 (Nov 27, 2013)

Performance on grades (i.e. no of cars that can be pulled up the grade) is affected by:
(1) the steepness of the grade,
(2) the pulling power of the loco -- which is based more on loco weight than on motor power,
(3) the rolling resistance of the cars,
(4) the weight of the cars, and
(5) the amount of track curvature (curves increase the rolling resistance of the cars, as the wheels rub more on the insides of the rails than on straight track).

It is impossible to predict how many cars your loco will pull, given all of these variables.

See my post #11 on this thread for a simple test that you can do to see whether your loco can pull your train up your intended grade. There is also lots of other good advice in this thread.

http://www.modeltrainforum.com/showthread.php?t=74321


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## D&J Railroad (Oct 4, 2013)

For a short 5' section of track at 4% grade, the switcher should be able to pull the string because about half of the cars will be on level grade at the bottom or the top.


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## CTValleyRR (Jul 26, 2014)

It's hard to give you a "is this feasible" answer. Obviously, you can test any loco you currently own. But whether future acquisitions will work is more of a crap shoot.

In addition to whether the loco will pull cars up the grade, there is the question of what will happen to the loco and cars at the top and / or bottom. Short wheelbase locos with two axles per truck (diesel) or 6 or fewer drivers (steam), will likely be ok, but there are no guarantees. The issue is that the trucks (diesel) or frame (steam) are fixed length, and can't bend. If there is too much front / rear overhang, the coupler will often dig in at the bottom of a grade, stopping the loco in it's tracks. At the top, the front wheels may come off the rails while the rear ones are still on the grade. This may not be a problem on dead straight track, but any horizontal variance will likely result in at least one set of wheels derailing (especially with the pilot wheels of a steamer). Your train may also uncouple as the loco levels out while the cars are still on the slope.

If possible, I would redesign and keep your grades to an absolute max of 3%. Additionally, you should use easement tracks (a gradual change in slope) at the top and bottom of steep grades.


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## time warp (Apr 28, 2016)

If all else fails, you'd have to split it. Just like the prototype occasionally does. 
Move the consist up the hill in 2 sections.
Build the line, then come up with solutions to get the freight moved.


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## DonR (Oct 18, 2012)

With a 4% grade the need of top and bottom easements
becomes even more critical. With your limited space you'll
want to plan for those.

You might consider a 2nd switcher as a consist or
helper when you bring a train our of your staging area.

Don


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## Gramps (Feb 28, 2016)

You may know this already but a 3% grade is a rise of 3 inches along a distance of 100 inches. I don't know how that factors into the size of your layout but good luck.


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## paulrail (May 22, 2016)

Thanks for all the info! There is more to grades than I realized. Based on everything you guys have told me so far I have decided to make a couple of small changes in my track plan and will be able to keep all my grades at about 2%. Mostly thanks to the "split the difference technique" (the lower track going down a grade about 2" while the upper track will rise about 2").

The changes will also allow me to use a 2% grade into and out of staging. I suspect this will work well but if I have any issues I will bring a portion of the consist out of staging and return for the rest. I don't know if that will look prototypical or not but it will add to operations . Another cool option would be to use multiple units to pull all 10 or so cars out of staging and leave them in the yard for a single engine to bring them on the rest of their journey.

I asked this question now because I'm trying to finish my bench work. If anyone else would like to offer any info or suggestions there's plenty of time 

Thanks again, guys
I love this forum
Paul


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## Lemonhawk (Sep 24, 2013)

A wise change. At 4% you might not even get the loco itself up the hill. Easement into the grade also is very important. Watching a loco suddenly change its attitude is dis-concerning and you know that bad things will eventually happen.


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## time warp (Apr 28, 2016)

paulrail said:


> Thanks for all the info! There is more to grades than I realized. Based on everything you guys have told me so far I have decided to make a couple of small changes in my track plan and will be able to keep all my grades at about 2%. Mostly thanks to the "split the difference technique" (the lower track going down a grade about 2" while the upper track will rise about 2").
> 
> The changes will also allow me to use a 2% grade into and out of staging. I suspect this will work well but if I have any issues I will bring a portion of the consist out of staging and return for the rest. I don't know if that will look prototypical or not but it will add to operations . Another cool option would be to use multiple units to pull all 10 or so cars out of staging and leave them in the yard for a single engine to bring them on the rest of their journey.
> 
> ...


Google Madison Hill near Madison , Indiana. Grade of nearly 6%, There was a pair of Heavily ballasted and geared EMD SD 7's just to move trains up and down the hill. A regular locomotive couldn't do it. There's a prototype for everything.


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