# Grades



## budinoh (Nov 25, 2009)

I have a layout that is a 20'x4' N-scale island with a scenic divider down the middle. On the "front side I have a double track main with 1 track on 2 sperate levels. The top level is 6" off the benchwork to topof roadbed. The lower level is 2 1/2 inches from top of roadbed to benchwork. That leaves me a 3 1/2 inch difference between levels. On the backside, the top track desends to the level of the lower track and the lower asends. Now, where would I find info on grades to determine what percent the grade needs to be and how tall the risers would be. I would like it completed in as little space as possible and still not have problems with my trains trying to climb the grade. 

Thanks,

Jeff


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## NIMT (Jan 6, 2011)

This is a really great chart!







Here is the site that has more important info! Here


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## JohnAP (May 4, 2011)

*Thanks Sean!*

Thanks for the chart and the excellent reference link! Allways more to learn and more to build!


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## lajry (Aug 4, 2011)

NIMT said:


> This is a really great chart!
> View attachment 12056
> 
> Here is the site that has more important info! Here


The usual way to figure % grade is 1 unit of rise per 100 units. A 1' rise in 100' is 1%, 2' in 200' 2%, etc. Doesn't matter what the units are just as long as it's units per 100 units.


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## budinoh (Nov 25, 2009)

So if I follow this chart correct, I need to have a run of 188" long in order to make up the 3 1/2" of level difference at 2%? Is 2% ok for modern diesels pulling 15-20 cars?


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## sstlaure (Oct 12, 2010)

On my last layout my max grade was 2.4% and I pulled 20 cars with a single Athearn Genesis SD60 no problem. This was with all "heavy" cars (NMRA weighted)


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## budinoh (Nov 25, 2009)

Thanks for the help guys. It appears after adjusting the subroadbed, I can get a smooth 1.75% grade over the entire 20' run and it is hardly noticable.


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## sstlaure (Oct 12, 2010)

1.75% is a great max grade.


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## Massey (Apr 16, 2011)

I have a nearly 5% grade on my HO scale layout and I can pull 10 cars up the hill with a Proto 1000 GP38-2 with no issues, I could prolly handle 15 cars easy and 20 would be really pushing it. 

On and older layout I had a 2% rise and I could get 30 cars up it with my Kato SD70MAC or SD80MAC but those are big and heavy engines. 

Massey


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## Denuch (Dec 8, 2011)

with grades if you add more than one loco does that make a diff. can you go steeper?


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## NIMT (Jan 6, 2011)

You can pull more cars with several engines. Grades require traction, and that can be more of an issues than power, modern diesels pull more weight on a steeper grade than do steamers! 
The only time it would be proto typical do run steep grades would be on a logging or mining run the tend to be sort but steep runs.
Yes you can pull somewhat steeper grades but there is a limit to working well. 2% to 2.5% is a good grade. Any steeper than that and you asking for issues. It's also hard on the engines to pull steeper grades.
Massey says he can pull 5% but that's very extreme for HO.


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## mwpeber (Dec 5, 2011)

Figuring out what grade is needed for your layout is tricky business... In an O gage layout I am designing, I think there is apx 200 inches of track to loop back on and cross itself, but don't know what grade I'll be working with yet. The open issue is how much grade I need.

Is there any rule of thumb for clearances for trains?


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## sstlaure (Oct 12, 2010)

mwpeber said:


> Figuring out what grade is needed for your layout is tricky business... In an O gage layout I am designing, I think there is apx 200 inches of track to loop back on and cross itself, but don't know what grade I'll be working with yet. The open issue is how much grade I need.
> 
> Is there any rule of thumb for clearances for trains?


Here you go.....

http://www.nmra.org/standards/sandrp/s-7.html

As far as grade - all depends on how strong your engines are and how many cars you want to pull at a time.


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## mwpeber (Dec 5, 2011)

sstlaure said:


> Here you go.....
> 
> http://www.nmra.org/standards/sandrp/s-7.html
> 
> As far as grade - all depends on how strong your engines are and how many cars you want to pull at a time.


So if I'm reading the standard correctly, I need 5 1/2" for O Scale from the top of the track.

Therefore the total rise = 5 1/2" clearance + 3/4" rail = 6 1/4"

Grade = 6.25" rise / 200" run = 3.1% grade.

That seems a bit steep based on conversation throughout this thread. I don't believe the engines I currently have are quite that strong. It seems as though I may need to find a way to get more track length for the rise.


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## sstlaure (Oct 12, 2010)

You also need to make sure to take into account any sub-roadbed material supporting the upper track (plyboard, etc)


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## waltr (Aug 15, 2011)

mwpeber said:


> So if I'm reading the standard correctly, I need 5 1/2" for O Scale from the top of the track.
> 
> Therefore the total rise = 5 1/2" clearance + 3/4" rail = 6 1/4"
> 
> ...


If you have a bunch of straight track, power controller, engine and cars then test what will work by laying track on a 1x6 (or 2x6). Prop up one end to create a grade (vary the height to change the grade). Check to see how steep of a grade the engine will pull without and with cars in tow.


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