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Right Grades

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  • Member since
    February 2005
  • From: Peak District UK
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Posted by cabbage on Sunday, May 18, 2008 12:45 PM
The question is fraught with peril!!! I tend to build locomotives that are 100% adhesive i.e. all the wheels are powered. This makes them capable of climbing and decending gradients far in excess of what would be normally considered sane...

For normal running a maximum gradient of 2% to 4% is the maximum.

I admit that I have build locos that were originally designed in real life for gradients of 1 in 7 and 1 in 10. Do I run them at that? Only for demonstration purposes!!!

regards

ralph

The Home of Articulated Ugliness

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Posted by lownote on Sunday, May 18, 2008 7:43 AM

I have a slightly more than 5% grade on my layout (Brass 332 track) and even though my stuff negotiates it I'd really like to get rid of the grade. I have an aristo mikado that will pull 12 freight cars, an aristo pacific that pacific pulls 4 heavyweight coaches, and a bachmann "Annie" that pulls 3 bachmann J&S coaches with no problem(see note below). But they are close to their limit and they slow down very noticeably as they hit the grade. Sure, that's what real trains did. But just like in real life it limits what you can do and it doesn't look right at all, especially since I'm mostly running mostly mainline stuff, not narrow gauge. I keep thinking of ways to redo it to minimize the grade.  The grade, by the way, rises 8 inches in about 11.5 feet. My measurement is not very precise

Here's a poor video I dashed off before I finished the track work and structures--the mikado is pulling 11 cars up just under a 6% grade with a curve at the top:

http://www.youtube.com/watch?v=g6Khdp6hWrw

I managed to get the grade down slightly and fixed the transition, so now it can manage the grade at lower speeds, but you get the idea 

 

So I agree that grades should be kept minimal, even though my own expereince shows you can get away with murder 

 

 

 

(NOTE: the freieght cars all have metal wheels, the heavweights all have 4 wheeel, not 6 wheel trucks, and the Bachmann coaches have had the scraper tab power pickups replaced by 2 ball bearing axles on each car  

Skeptical but resigned
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Posted by ttrigg on Friday, May 16, 2008 8:07 PM

It looks like this one is headed to an argument heated discussion. Of course, anything can be done. The question is how practical is it?

I have to agree with Capt. Bob, in that all grades above 0.00% (absolutely flat) place varying degrees of strain on an engine. The more the strain the quicker the motor will burn out. Curves also add strain, they also add the potential of wheel bearing damage due to the lateral loads on the wheel sets. The only way to completely reduce these strains and loads is to run our trains in an absolutely straight and absolutely level point to point operation. That would not be much fun at all.

Life presents us with many choices; the ground we run our trains upon gives us many challenges. Bridges and embankments add to the scenic splendor of our mini empires, as well as reducing the respective grade. Then there are the times we do what we know should not be done. In my case I have one grade that approaches something in the neighborhood of 23%, that is on the trolley line up to the top of the falls. My main lines are at something less than a half percent. For planning purposes we should always plan for the shallowest grades possible and the widest curves possible. As terrain considerations restrict our operations we must accept the limitations on the operation of our equipment, and the added wear and tear upon our equipment.

Tom Trigg

  • Member since
    August 2006
  • From: The English Riviera, South Devon, England
  • 475 posts
Posted by Great Western on Thursday, May 15, 2008 4:38 PM

My preference would be to avoid any grades if at all possible.

However, one side of my garden has a lovely, but large, magnolia tree which necessitates a 2% long grade either side of the trunk.

As my railroad is not large - around 180ft. single track with passing loop - I do not run long consists. Generally my Annies, RS3 and Centre Cabs will tackle the grade without issues when hauling up to seven boxcars or similar stock. 

Alan, Oliver & North Fork Railroad

https://www.buckfast.org.uk/

If you don't know where you are going, any road will take you there. Lewis Carroll English author & recreational mathematician (1832 - 1898)

  • Member since
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  • From: West Texas
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Posted by imrnjr on Thursday, May 15, 2008 9:14 AM

I have a  22' run of 5% and another 60' 2-3% grade in my railway on stainless track,  my Big haulers, LGB Forney and 3 truck shay all handle them with a prototypical slowing and then increasing back to speed  as the grade returns to 0%.  The 5% does limit the BH's to 2-3 light cars to keep from stripping the gears.

MarkCowboy [C):-)]

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  • From: US
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Posted by Curmudgeon on Wednesday, May 14, 2008 5:38 PM

The difference is in the cleanliness of the rail as much as the inherent slipperyness of said rail.

 The stainless was by far the most slippery, if I recall.

  • Member since
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  • From: silver spring, md
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Posted by altterrain on Tuesday, May 13, 2008 7:56 PM

of course, Dave is a diehard who makes his guests run trains in hurricanes -

 

I run mostly track power on my very slippery stainless steel rail with 2.5-3% grades and have been known to pull 20 car consists Wink [;)]

 

-Brian Evil [}:)]

btw - there was an interesting article in GR a couple of issues ago written by a young garden railroader who compared the tractive effort on various types of rail in different conditions as a science fair project. Summarizing his results - he did not show vast differences with different metals under various conditions.

President of
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Posted by Curmudgeon on Tuesday, May 13, 2008 6:50 PM

Depends.

I have 150' of continuous 4% grade, fairly common for narrow-gauges.

EVERY operating session I do cleanup runs up that grade with 28-34 loads with ONE OLD Bachmann Shay, no wheelslip in dry weather.

Most of our locomotives pull just fine on that grade.

I use only battery r/c, and the track is old aluminum.

Do not limit yourself unless you are using slippery rails.

Even then, the prototype made up short trains or called in helpers.

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Posted by Anonymous on Tuesday, May 13, 2008 3:07 PM

I would tend to agree with Capt. Bob ...... I did the big nasty with 4-5% grades in spots to give myself a great deal of elevation for mountainous terrain. While it looks pretty cool, it IS hard on the locos, and requires me to very carefully set my throttle to avoid lugging down or runaway conditions during operation. Keeping things near 1-2% is best.

 Trainman 

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  • From: Slower Lower Delaware
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Posted by Capt Bob Johnson on Thursday, May 8, 2008 8:36 PM

While some will say that you can go up to a 3% or even a 4% grade, it is impractical and puts a strain on your train and greatly reduces the number of cars a given loco can pull up the grade.

1 - 2 % is both practical and doable!  I used 1% on the curved sections and 1.75% on straight sections.   This permits a pretty steady speed without having to mess with the throttle while climbing.

A 1% grade would be 1 inch of rise in 100 inches of run, or 1" in 8'04" of length.  To be practical a half inch rise in the length of a 4 foot level would be close enough!

  • Member since
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  • From: Orange County, CA
  • 10 posts
Right Grades
Posted by Railkid on Thursday, May 8, 2008 7:13 PM
I was wondering what the typical grade was for a garden railroad. In. per 10 ft. would help.

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