Inclines / Declines ??

I try to keep my grades at or below 2%

But, there are more factors than grades that must be considered, like what is the lenght of your trains, what is the curve radius. Are trains on the up grade and curve at the same time. and so on.

 

Can you post the track plan?

 

Can you post

I haven't had traction tire or coupler problems.  I have grades all over the place, steepest being about 3.6% or so (can't remember exactly).  Been running this layout for a bit over 2 years.  I usually run freight trains of 15 to 20 cars with modern Lionel and MTH engines.

 

See videos on my youtube channel below.  

I'm glad you posted this cause I was trying to figure out how you get the %. I'm still lost on all of it. My old layout I would go about a inch a foot or 1/2 if it was a curve. My engines didn't really seem to have a problem but with layout I'm trying to do it all right. I have a 9 foot area that I need to get up about 8 or so inches.

October Thread on grades.   Steeper grades require more power.

Nate.  It's "rise over run" for slope or grade.  Multiply by 100 to get %. So you have an 8 inch rise "over" (meaning divided by) a 108 inch run. 8 divided by 108 is a 7.4% grade.  

 

You might consider splitting the grade by going down on the lower track, and going up on the upper track.

 

Also, the opening on store bought tunnel portals are 6.5 inches high.  If you do the benchwork so that there is no support beam at the crossing, you can set the height difference at 6.5 inches from the top of the bottom platform to the bottom of the top plywood.  If you are using 1/4 inch plywood, then you need a rise of 6.75 inches.

 

If you are able to split the grade along the same 9 foot area, then each grade is 3.375 inches over 108 inches, which is 3.125%.  

 

This is theoretical, but you have to play around with the idea to see if you can make if fit with your real word layout situation.

 

Nate / pennsy48 - I could be wrong, but I think the easiest way to measure grade is calculating incline/decline inches per 100 inches.  So, 1 inch of rise in 100 inches is a 1% grade; 2 inches of rise in 100 inches is a 2% grade and so on.

 

Peter 

You don't need to go by someone else's arbitrary standards for grades. Steep grades can be an interesting operating challenge for a model railroad; you just need to figure what will work reliably for the trains and equipment you want to run. The best way is to experiment with your own equipment. Vertical curves at the top and bottom of a grade should be gradual to avoid coupler problems.

 

Salida grade approaches 5%. The Madison Incline is 5.89% for more than a mile. Those are extremes, but they are prototype examples of what is possible.

 

Sharper 3-rail curves create additional drag for trains, and it's a good idea to reduce your maximum grade somewhat through a long sharp curve.

 

For big layouts that run long trains it makes sense to keep mainline grades at 2% or less. For home layouts with shorter trains you can make your own standards based on what works for you. Steeper grades may allow a more interesting track plan in limited space.

 

Model railroad guru John Armstrong had grades up to 3.5% on his O-scale "alternate mainline", if I remember correctly.

As a noob, I think Ace is 100% right. My initial personal limit will be whatever my RailKing 4-6-0 steamer can manage when pulling 10 cars plus a caboose. That assumes the RailKing diesels I buy will be able to manage the same grade. I'm hoping a 4-4-0 will also manage it, even though I only intend for it to pull a mailcar, 2-3 passenger cars and a caboose. I assume adding a curve to the grade will reduce the maximum a bit. I should mention that I have no plans to collect engines, I expect to limit myself to 5, the largest being a 4-8-4 Northern class and the smallest being the Old West 4-4-0 American class all able to navigate 031 curves.

DoubleDAZ - yeah, that's what I was thinking (and testing) till I heard about the traction tires prematurely wearing out and the couplers giving up due to repeated undue strain.  Basically, the concern isn't the "here and now" (how many cars my locos can pull), it's the problems that steeper inclines cause "down the road" that has me losing sleep.   

Was hoping people could shed light on this stuff. 

 

Peter

Mike CT– thanks for the hyperlink.  I actually had read that thread, but found it partially helpful.  And thanks to everyone else for all the helpful advice!  

 

I’m running a double main 072 and 081 Atlas O, if that’s at all helpful.  I guess what I’m saying is that, as a newbie, I’d like to go into this with eyes open (given it’s a “permanent” layout).  Most people tell you not to exceed “X” grade or tell you what grade they use on their layout.  Frankly, this doesn’t get to the heart of the matter – an understanding of why.  Granted, it’s not rocket science.  Steeper grade means greater chance of trains spinning their wheels and going nowhere.  But then, there are so many differing data on what’s OK.  For instance:

 

• MTH and Lionel both offer trestle sets each of which exceeds a 4.5% grade. 

 

• Old schoolers atAmherstshow told me not to exceed 2% due to premature wear to traction tires and extra strain that will make couplers open on their own.  

 

• Another OGR forumite said 1.5% is max.

 

• Rich Melvin (in the linked thread) says 2.5% is OK. 

 

• John Armstrong’s book says even very steep grades (7% if memory is correct?) are OK if run is short (something about full weight of train not being realized before loco is through incline).        

 

• LHS club told me an incline over 2% isn’t “prototypical.”  But I can never understand the “prototypical” argument.  First, it’s a father-son project and my 9-year old twins don’t really care about “prototypical,” they care about trouble free fun.  Second, the “prototypical” O gauge crowd can’t be serious – I mean aren’t these the same people using 3-rail track and running curves that aren’t anywhere near “prototypical” (which would be like 0180 or more)?

 

From all the helpful advice here, it sounds like 2.5% might be OK.  

You're right, Peter, I'll be interested to see if anyone chimes in about tire wear. I hadn't thought of that, but then maybe I'm assuming the 4-6-0 will be able to manage a grade far steeper than I plan to use. Even then, maybe any increased tire wear will be acceptable.

As far as protypical goes, I believe one's desire to do only what is generally found on "real"  railroads is more determined by one's available space. If you have a lot of space, 2% grades can be a reality, but try to do that in 4x8. I'll technically have 10x21 to work with, but by the time I account for 2 doors I need to access and 2 reversing loops with 042 curves I'm probably looking at a 16x10x13 bi-level horseshoe with 4' widths on the ends for the loops. So I should have 300" for a grade giving me a 6" rise for 2%. Unfortunately, my temporary layout is only 6x11, so I'm probably looking at 3.5% or so.

does anyone know the grade of lionels fastrack graduated trestle set 6-12037?

In todays modern era it is not as much an issue as it was in the past.  I have designed many 3 rail layouts and in the past if the layout was to be a 'display' layout the levels were designed to be as level as possible so no operator intervention was required.  Operating layouts required an operator at all times so some grades were tolerated.  Today with EOB and TMCC/DCS speed controls you can have some grades and run the layout either way, display or operating.  We are currently building a 20x40 ON30 layout with 2% mainline grades, reason for the shallow grades, we can run longer trains with the very small and light ON30 engines without adding extra weight.  Just my 2cents worth!  Russ

You should not have problems if you don't have a bunch of tight curves on that 2.5% grade and if you handle the throttle properly.  It will make a difference if your equipment is properly lubricated and your track is clean.

 

If you want to run trains that approach the "tonnage rating" of your engine, then you'll need to think before you increase speed on an ascending grade, and if you do have to increase speed, do it with restraint and finesse.  Reduce throttle as you crest the grade, to avoid increasing speed until half of the train is over, and you won't break couplers.

Thanks.  What exactly is considered a "tight" curve?  As I had mentioned, my curves will be 072 and 081 but isn't all of this relative?  I mean, if the manufacturer says the loco and cars can negotiate 045 curves, then 072 sounds great.  But if the manufacturer states the loco and/or cars need 072 curves, then isn't 072 considered "tight?"

 

Peter 

Ace is right.  I have a 4% grade for many a year no need for new traction tires yet on either the premier or the rail kings that run that line.  The only coupler issue I have had is on the flat section with a lionel slag car. 

 

Did these people come from Iowa or Kansas? I think people from that section of the US are just more comfortable seeing everything flat as it seems realistic to them, your experience may be different ;-).

A digital angle guage comes in very handy.  It takes the guess work out of grades.  Every shop should have one.

 

Nate, it can definitely get complicated, but basically you divide the height you want to raise the track by the length of your run in inches and multiply by 100. In your case, you want to go up 8" in 108" (9') of track. 8 divided by 108 is .074 times 100 giving you a grade of 7.4%.

Since that is too steep, you'd have to start your grade on one side then go around a curve and continue up the other side. If your curve is 60" across (054), 8 divided by 168 would get you a 4.8% grade at the end of the curve and 8 divided by 276 (up both sides) would get you down to 2.9%.

However, if you have say a 5x9 table, some of the side will be cut off by what is needed for the curve. A 5' curve would cut at least 2.5' off each side. Now you're down to 8 divided by 216 for a 3.7% grade. There will be some additional drag from the curve, so you're really looking at 4% to go up your 8" on a 5x9 table.

And don't forget that 8" is from the top of the rails to the bottom of the next level and that's all from the edge of one end of the table around to the edge again. Effectively you'd have to completely circle the table to rise the 8". If you lower the rise to 6", you'd be at 2.2% circling the table and could go along one side of the oval and be at 4.4% at the end of the curve. And it's always best to measure the actual run than to use rough measurements like I did. Of course, it's easier still to let software do it for you. That way you can alter the height/length and not have to do the math.

An easy tool to make, a 1/2 inch block screwed into the end of a 25 inch piece of stock.  Place a small bubble level on it and as you raise the road bed you make the bubble level - level.  That is a 2% grade.  Russ

 

That's a great idea, once you decide on a grade; 1/2" for 2%, 3/4" for 3% and 1" for 4%. Looks like an easy way to do risers where your benchwork is 24" or less on center. Pretty cool how 25" just happens to overlap standard benchwork supports. However, this doesn't tell you if a given train will have a difficult time with a steeper grade and it doesn't tell you how long the run up needs to be for a given grade. For the latter, you still need to do the math.

For measuring percent of grade on an existing layout, smart phones have an APP for that. 

 

Clem

Clem can you post the name of that app and will it work on a iPhone?

XClinometer is one I found that appears to have come from the iPhone and is now available for Android. I'm sure there are others.

Hey nate - I think your footer used to say " Semper fidelis." If so, thank you so very much for your service. Like my dad who was a leatherneck in Vietnam used to tell me - freedom is not free.

Rich Melvin (in the linked thread) says 2.5% is OK.

 

Rich is correct.  2.5% grades are perfectly acceptable for main lines on large O scale model railroads.  Most modern large O scale diecast steam loco locomotives (Mikados or larger) or pair of powered diesels should be able to handle a train made up of 10 scale length passenger cars or 20 freight cars on such a grade.

 

MTH and Lionel both offer trestle sets each of which exceeds a 4.5% grade.

They do.  And most train set locomotives can pull the cars they came with up these grades.

 

LHS club told me an incline over 2% isn’t “prototypical.”

 

In Massachusetts that may be correct.  Elsewhere in the US many railroads contend with steeper grades.  In the Pacific Northwest all the transcontinental railroads had to contend with 2.2% grades on their main lines. 

 

John Armstrong’s book says even very steep grades (7% if memory is correct?) are OK if run is short (something about full weight of train not being realized before loco is through incline).   

 

While even a short length of 7% would be extreme, Mr. Armstrong'd basic point is correct.  On the the GN main line both Stevens and Marias Pass have short sections that are well over 2.2%.  But since the length of the steeper portion is much less that the length of a freight train they don't set the ruling grade.

 

A ruling grade is the grade that must be considered when assigning power to a train.  The ruling grade might be less than the steepest grade, as mention above.  A ruling grade might also be higher than the simple rise over run when calculations of the increased drag caused by tight curves are accounted for and is referred to as a compensated grade.

 

For O-72 and larger curves it is not normally necessary to compensate for curves on model railroad grades.

 

Your 2.5% should work out well.  Just be aware that you are modeling mountain grades and you will get some real world operational needs as a result.  If you want to move freights much over 25 cars you will need to start thinking about where lighter cars are placed in a train, adding manned helpers or running distributed power.

 

If you would like to take a look at prototypical mountain grades on the B&O as well as in the western US and Canada check out this link.

 

http://www.lexingtongroup.org/...Grade%20Profiles.pdf

 

 

If you go into the ITunes app store and search for Clinometer you will find a large number of apps, many of which are free

 

Al

It may be interesting to note that the French high-speed TGV lines use grades up to 4% to maintain straighter alinements cross-country. They simply power their way through it, presumably with the advantages of momentum. 

 

Ladies & Gentlemen,

   Ace's anlysis indicating that steeper grandes can be used are absolutely true,

this also depends on which track you are using, I have engineered FasTrack on some pretty steep grades, knowing my older Magna-Traction Lionel Engines and my powerful Williams GG1 & E44 could pull numerous rolling stock without any trouble. 

On the other hand I would never engineer the same grades with my MTH RealTrax.

The trestel slippage is way to great, for using that particular track on steep grades.

I agree with Ace there are many different variables when planning,  both the engines and the track must be considered when engineering steep grades.

PCRR/Dave

Dave, thanks for the tip on Xclinometer - I just download it (free) for Android.  I checked it against some known angles and it works very well. 

Jim

You're welcome. I'm on the road, so I haven't been able to check it. Glad to here it works.

Yes ...it does work on iphone.  just go to the App store on phone and type in Clinometer. There is a few.

If I had to limit myself to 2% or less I couldn't have a two level set-up on my 5x10 layout. It rises at 4%. However, I rarely pull more than 5 cars and it's a pretty short climb. Coming down the train definitely picks up speed so you do need to pay attention but even my 6 year old daughter is able to easily keep it under control. I think the 2% rule only really applies if you're talking about longer trains and larger layouts. I'm pretty sure the FastTrack elevated trestle set is more than 2%.

OK, sounds like 2.5% (or even 3%) is fine.  Thanks for the responses.

   

Again, I don’t really care what actual prototypical grades may/may not be – frankly, it’s irrelevant for purposes of having a trouble-free (to the extent possible) model pike in a limited space.

 

By the way – in terms of confirming grades, there are a ton of free apps for iPhone, and just wanted to share that I just pulled the trigger on one for around $35 from Micro-Mark that’s supposed to be extremely accurate and stable.     

Both.  But mostly command control. 

My PRR Panhandle has two grades of note:

• The mainline had a 6.99% approach to a bridge that I reduced significantly, probably to around 4%.  Train performance has visibly improved.
• A hidden yard lead of undetermined grade (estimated at 6.4%) that descends to a storage yard.  Part of this is on an O72 curve.  This lead is used exclusively by a Lionel Alco S-2 diesel switcher.  Descending is (obviously) not a problem.    In order to ascend the lead, either by pulling or pushing, I have to limit the cut to 4-5 cars.  This makes for a fun operational step.

Bottom line:  If you're in the 4% range, I certainly don't see a problem unless you've got a known anemic puller.

 

George 

"the advantages of momentum" and no 100 car freight trains!   Russ

George, The issue isn't about whether a locomotive can pull x cars up a grade of 2.5 or 4 percent. Frankly, my Lionel Polar Express conventional train set locomotive was doing fine pulling 12 cars up the MTH trestle 4.9% grades on our temp layout. The concern was about the long-term effects. At the top of this thread I had mentioned the old school hobbyists at the Amherst train show that scared the crap out of me for having a plan with 2.5% grades. They said it would mean premature traction tire wear and that couplers would eventually give out and pop open because of the constant undue stress.

If you want to be concerned about traction tire wear and coupler stresses, then the issue isn't just grades. Total drawbar load depends on grades, train length, curve drag and rollability of the wheels on your train cars. You can have a flat layout and still pop couplers or traction tires with a heavy train. I found that 30 cars is about the limit for mostly postwar cars behind my Big Boy on a nearly flat layout with O72 and O54 curves. The limiting factor is couplers sliding over-and-under. I consider it part of the engineering challenge of train operation.

 

Another factor for traction tire wear is, how much mileage do you expect to run up on your trains? Because traction tires (and other things) will eventually wear out accordingly.

 

I have some O-gauge locos with traction tires, but my preference is for no traction tires, all-wheel drive, and heavy weight for traction - like real locos.

 

If someone has an idea to build a layout of a certain size, with a certain minimum radii, and expects to run trains of so many cars, and wants to consider using a certain percentage of gradient - then it would be possible to offer a more educated opinion of whether that combination of criteria is advisable.

One thing to watch on the steeper grades is at the beginning and end of the grade. On a steep grade some engines can short out the front coupler on the 3rd rail. Easing in and out of the grades can eliminate this and possible uncoupling at the top of the grade. In my opinion the grade doesn't look as steep when the train runs over it.

Ron