# power question along with track grade



## krogerssolar (Jan 8, 2009)

i will post this here as welll

hi everyone i need help with making some kinda grade along with how bad this might effect my battery power i am making a 11' by 11' deck which on my low side is about 8'' off the ground where i plan to run my track up to a switch yard that will be built on it what i need to know is how to make the grade from the ground level up to my decking along with what impact this might have on my batteries. any idea'sThanks Kevin


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## Semper Vaporo (Jan 2, 2008)

How much room do you have to build an approach to the deck? You will want the grade as gentle as possible. Some folk get away with 4 to 6 percent, but that would be hard on the engine gearing and battery power if you are pulling a train. 

What radius (or diameter, if you are so minded) curves are you planing (or need to have to accomodate your engines/trains)? 

If you want to try to keep the grade to, say 2 percent, then to get a rise of 8-inches you need 33.3-ft of straight run. If the track must be curved then the grade needs to be even lower (longer), since curves add their own resistance that is just as bad as grade. 

To gain some extra length you could run the grade track parallel to the deck side and then curve onto the deck nearer the back of the deck. 

If you are planning, say, 4-ft Radius then you could gain an additional 7-ft of straight run to the rise by running parallel to the deck but 4-ft away before curving the track to the deck at the back. 

Subtract 7-ft from the 33-ft then the grade must start 26-ft from the front edge of the deck. That is a long way in some yards and you may not have room for that. So you may have to break that into smaller straight sections with lower grade curves between them. 

If you don't have the room then you will just have to put up with steeper grades or shorter trains. Some get away with it, and others complain of damaged engines.


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## krogerssolar (Jan 8, 2009)

i would say i have 30' to around 40' from where my mainline will be to this deck my dash-9's are the biggest loco i own at this moment so my curves are 8' DA at this moment im thinking of going to 10' DA sometime


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## Semper Vaporo (Jan 2, 2008)

Just for grins, I made a crude sketch of ONE possible track plan to gain 8 inches of rise to an 11-ft x 11-ft deck. I got it to fit in a 17-ft. by 31-ft. area (including the deck in one corner).

I wanted to keep the track at least 6-in. from the borders of the area.

The curves of 10-ft diameter (5-ft. radius) all will drop the elevation 3/8-in. in 90-degrees. The length of the curve is 7-ft. 10 1/4-in (94 1/4-in.) long (one quarter of a 10-ft diameter circumference) so the "grade" (not counting the additional drag/grade caused by the curvature) is 0.4-percent. The curves should have easements into them but I didn't take that into account.

All tangent track grades of less than 2-percent.

Do you happen to have Google Sketch-up on your computer? I will send you the file I made for your amusement if you want.

Basically the plan begins 6-inches from the back edge of the deck where a 5-ft radius, 90-deg curve begins. The curve drops the elevation 3/8-in. from 8-in. at the deck to 7 5/8-in. at the end of the curve.

Then a tangent track of 18-ft. 8 1/4-in. (224 1/4-in.) drops the elevation from 7 5/8-in. to 3 1/2-in. (4 1/8-in. drop) , which is a grade of slightly over 1.8-percent.

Another 90-deg curve drops the elevation another 3/8-in. to 3 1/8-in.

Off the end of that curve a tangent track of 4-ft. 5 3/8-in to an elevation of 2 1/4-in. for a grade of 1.6-percent.

The next 90-deg curve drops the elevation to 1 7/8-in.

At the end of that curve a tangent track of 7-ft. 7-in. drops the elevation 1 5/8-in. to 1/4-in. for a grade of 1.8-percent.

A final curve drops the elevation to 0.0-in. in about 60-degrees (5-ft. 2 7/8-in., 62 7/8-in.), (the grade is still the same as the other curves).

Total track length is 714 1/4-in (59-ft. 6 1/4-in.) so the average grade is 1.12-percent, but Ruling Grade is slightly over 1.8-percent (although the curves may be more than that, but I have not taken the time to figure out how to figure out what they might be).

All the tangent track should have had the same grade, but due to my leaving Sketch-up with a resolution of 1/8-in. round-off errors crept in. But I don't think that matters much in this exercise... Nor would it be accurate in the real world when trying to make Mother Earth obey any attempt at a finer resolution!

It leaves a center area of about 13-ft. x 16-ft. which is a nice sized area for a loop of track and some modeling of a town and countryside.










I have already thought of a better layout!


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## Greg Elmassian (Jan 3, 2008)

A piece of advice, leave the curve level, and drop on the straight... even though the tangent track will have a steeper grade, you won't have derailments from wheels lifting off the track when the track is curved. 

I know, have a place that goes from ground to 21 inches up, and then a hairpin curve and then a 5.5% downgrade... have run 50 car trains reliably on this. 

You can see my site under layout development and progress. Trust me, keep grades off curves. 

Regards, Greg


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## markoles (Jan 2, 2008)

I don't have any problems with curves on grades and I have some pretty significant grades with S curves in them. You need to make sure that your track is level side to side. As long as you aren't trying to pull or push 100 cars through 4' diameter (2' radius) curves, stringlining your trains will not be a real issue. I have never had a problem with my poorly graded railroad with curves on grades. I find it is best to have a consistent grade from start to finish. 

The proposed drawing above looks like a good solution. I would work with that. 

Mark


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## Totalwrecker (Feb 26, 2009)

My railroad has more curves than straight track, theres no way I could gain the elevation needed on straights alone! 
I think it's better to have a consistent grade through the curves than to have steeper straights between flat curves. 
Of course if your trucks are stiff and un-sprung any grade change can present problems. 
I also use super elevation on my curves which helps the equipment to lean into the turn and track better. 

John


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## Greg Elmassian (Jan 3, 2008)

When you have the transition from level to a grade on a curve, you WILL lift some wheels on 3 axle trucks and steamers. This is what causes derailments. 

If you don't run these locos you are pretty much ok. If you do, you will have problems. The physics of how much "worse" a grade on a curve is for drag is a reasonable tradeoff for making the curve flat and more grade on the tangent, it all is pretty much equal. 

So go ahead and put your grades on curves, but realize that you may limit train length or the types of locos, and after it's all done, very few people go back and re-do all the track. 

Mark, do you run larger locos, like 3 axle trucks? What train lengths can you achieve. John, I think the "scale" of your track is much larger than the OP's, so your grade transitions are much more gentle. 

I'm looking at what he wants to do, in this specific situation. 

Regards, Greg


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## Totalwrecker (Feb 26, 2009)

All steam all the time! a 2-8-0 has the longest wheelbase. 
It's the transition not the curve, IMHO, too radical and wheels will lift, then if it happens at a curve there may be derailments, but if the transition is gentle there shoudn't be any wheel lift no matter whether curved or straight. My big curves are all 10' d, not very big really. aprox 15"r in HO! No wheel lift on my road and it ain't flat. I'll use about 3' to make the change from flat to grade with a spiral curve. 
If you start the grade on straight, there should be no wheel lift through the curve. Unless you add another transition to flat. In this scenario it's the grade to flat transition that is the culprit, not the flat to grade. So if you add a transition just before the flat curve you could be building in a problem rather than curing it. 

While true a curve causes drag, it also helps the drivers bite the rail better and increases traction... an observation. So if the load is wirhin the locos load limit a curve won't notiably slow the train. Note; I rarely run trains at maximum load, rather I prefer shorter prototypical train lengths. 

Perhaps our situations are a tad different, but on an open forum, I think it may help others reading along to know that curves on grades can work just fine. 

John


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## jmill24 (Jan 11, 2008)

Here is a link to a video of long 3 axle truck E8's negotiating incline on curves, an "S" curve and the summent is on a curve where it goes fron incline to decline. Also pulling 11 USAT Stream Liners which are very heavy cars and also about 3 feet long. This video was the test run of the new high road...............Jim

http://www.youtube.com/watch?v=4p8yTFMQyHc


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## markoles (Jan 2, 2008)

Greg,

Yes, I have two mikados and a mallet and these do not derail in the transition area of grades on curves. I thought you were aware of my roster, since we've chatted about some troubleshooting in the recent past. 

The main thing that needs to be incorporated to any grade, be it on a curve or tangent, is the transition from 0.0 to whatever the grade is. In other words, you shouldn't go from no grade to full grade between two pieces of sectional track. You've seen this video, right? 





So, basically, I don't agree with your point about having a steep grade on straights only and to avoid them on curves. It would seem that by having the steeper grade, you would put more stress on the train after it has transitioned out of the grade than if you had a consistent grade all the way through. Wouldn't it stand to reason that if it was better to do it that way, the real railroads would do it like that? 

Also, please count the cars in the freight train, somewhere around 25 or 30. I think at the end of this particular day, I ran about 38 cars behind that mallet. The grade up to the bridge is probably in the 4-5% range. It is not a typical train I pull because I usually don't have the time to put it all out. The switch and temporary tracks in the foreground were not well laid or leveled, and we did get the occassional derailment there due to the side to side level being way out.


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## East Broad Top (Dec 29, 2007)

I'll echo the opinions about grades on curves being absolutely acceptable--in many cases, mandatory--garden railroad engineering. You're far more likely to have derailments at vertical transitions in the track, especially those at the starts of curves. By keeping the grade constant through entire length be it curved or not, you eliminate the vertical component of the equation, and keep the wheels on the rails where they're supposed to be. Yeah, the curves add a bit of extra drag. You goose the throttle a bit, just like the real thing. That's far preferable to having to re-rail at four or five different points on the grade just because there's a transition from level to grade. 

As for the grade and its effect on battery life, it's most likely going to be a wash. Remember--what goes up must come down. Going up, you're pulling the train, drawing more current. Going down, the weight of the train is pushing against the locomotive, and current draw is reduced. My dad's railroad has 10' diameter curves on 4% grades (and a stretch of 5% with a small section of 8% for around 20' or so.) I get similar battery life running on his railroad as I do running on mine, where 2% is my steepest grade. The overall load (length of train and speed at which it's being moved) will have a far greater impact on battery life than the grades over which you run. 

Later, 

K


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## Greg Elmassian (Jan 3, 2008)

Mark & John, I agree, the transition is the key. Also, nice to see your layouts, but they are not of the scale of Kevin's situation, and that's all I am talking about. 

What I thought I made clear, but obviously not, is that there is such a short distance for the track in this case to get to ground level, that it's likely the transitions are too abrupt AND on curves. Therefore keeping the grade off the curve allows more abrupt transitions, since the wheels will not be skewed when they "land". (again, you will catch some "air" on 3 axle Aristo, non sprung steamers, etc.) 

I've learned this by a lot of experimenting, and laying on my belly watching locos without sideframes and seeing wheels lose contact at transitions. It seems that there is never enough room for good gentle transitions unless you have acres of space, and this case surely does not look like a large acreage. 

Kevin, while they can work, I will never use the phrase "grades on curves being absolutely acceptable".... 

absolutely is a very strong word... "may be acceptable", or something less "absolute" than absolutely... 

Regards, Greg


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## East Broad Top (Dec 29, 2007)

Greg, if you can demonstrate an instance where it's not acceptable to put a grade on a curve, then I'll agree with your take on "absolutely." But model railroaders of all scales have relied on grades on curves from the earliest days of the over-under figure 8. It's SOP in model railroad construction. I've never seen a reference to the contrary. 

I see what you're driving at--it's the twists and vertical transistions in the curves that lead to derailments. But each time you transition from grade to curve back to grade, you're introducing a vertical curve into the equation. By keeping everything on the same grade, you eliminate those vertical curves. Yeah, you've still got some minor twisting on the curves, but the degree of that is dependent on (a) the degree of curve, and (b) the steepness of the grade. By minimizing both of those--which you do by going as wide as possible on the curves and allowing all of the track from the high to low point to be on grade--you minimize the unevenness on the cuved track, and significantly reduce the potential for derailment. 

There are two "rules of thumb" in garden railroad construction. First, keep your curves as wide as posslble; second, keep your grades as minimal as possible. To suggest keeping your curves flat and your grades only on the tangent (straight) tracks makes those rules mutually exclusive. To minimize grades, you'd need long straights, which requires tight curve. To keep your curves as wide as possible, you minimize your straight tracks, forcing your grades to be steeper. 

I don't think there's anyone who's been in this hobby more than a year or two who hasn't spent lying on their stomach with a spirit level trying to figure out where the twist in the track that's causing derailments is coming from. A curve needn't be on a grade to cause troubles. Track twists regardless. That's why manufacturers insist on the deep flanges they use. 

Later, 

K


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## Greg Elmassian (Jan 3, 2008)

The flanges are there for more than the twists. Arguing on the forum is a waste of time. 

If you ever make it to my house, I'll demonstrate for you and I'll guarantee you will understand what I am saying. 

No more wasted breath here, I have better things to do. 

Greg


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## East Broad Top (Dec 29, 2007)

I fully understand where you're coming from with your proposition. With the curves on the same plane, the rigid wheelbase truck riding over it maintains constant 4-wheel contact with the rails. The vertical curves are only on the tangent track, so if the truck has to lift (due to more than 2 axles), the rails are always right beneath the wheels, so there's no tendency for the flanges to want to climb the rail. That's great in theory. 

A piece of advice, leave the curve level, and drop on the straight... even though the tangent track will have a steeper grade, you won't have derailments from wheels lifting off the track when the track is curved. 

You've got a 15' x 15' square area to build a helix, and you've got to move 50-car trains up through it. It's hidden from view, so you definitely don't want any derailments inside. Taking your advice, the "derailment free" approach would be to use tighter, level curves and steep tangents to make up the difference in elevation. How is that superior to the "typical" helix construction of the widest radius possible, and a smooth, consistent grade throughout the spiral structure? Certainly history has long demonstrated the latter to be sound engineering. 

Later, 

K


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## Greg Elmassian (Jan 3, 2008)

"The vertical curves are only on the tangent track, so if the truck has to lift (due to more than 2 axles), the rails are always right beneath the wheels, so there's no tendency for the flanges to want to climb the rail. That's great in theory."

It's not only great in theory, it's true. That's all I am saying. And you have to remember that on a "crowned" transition, one of the axles on the "end" of the motor block goes into the air. Loses contact with the rails. Take the sideframes off an Aristo 3 axle loco and you will see that this is true.

(USAT does not have this problem, because they are 2 axle trucks with the third axle floating like a pilot)

Take a look at what a mikado does, with it's rigid wheelbase and 4 axles.

In fact, track with perfect crosslevel negates the "rotational equalization" of the Aristo gearboxes, they have NO up and down motion for the axle per se.

Just warning people who are learning the hard way. Sure you can do grades on curves. Would I advise a newcomer to do it if it could be avoided? **** no.

Greg


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## East Broad Top (Dec 29, 2007)

one of the axles on the "end" of the motor block goes into the air. Loses contact with the rails. 
It's not the notion of curves on a grade that's at the heart of the issue. Practical experience has long demonstrated that to be sound engineering. I've run rigid-wheelbase locos up and down the 4%, 5' radius curves on my dad's railroad for--literally--decades without ever derailing. It's a _change_ in grade on the curve that introduces the problem. As the grade changes, that's when it creates a hill or crown which causes issues for the rigid wheelbase locos. It's going to do that on the straight or curves. Curves are a bit more problematic, because as the rail turns under the wheel, the flange may have a tendency to climb on top of the railhead instead of being pushed to the side by the inside edge of the rail. Avoiding _changes_ in grade on a curve is absolutely advisable. Your solution is to put the change in grade on the straight where it's less problematic, and keep the curve absolutely level. My solution is to simply not change the grade. Keep the grade constant throughout the stretch of track regardless of what the curve is doing, and you avoid the crowns and dips inherent in the changes of grade. Where you do have transitions from one grade to another (be it level or what-have-you) it should be done smoothly over a few feet of track. If it has to be on a curve, make it over a few more feet of track. 

Sure you can do grades on curves. Would I advise a newcomer to do it if it could be avoided? **** no. 
I find it preferable to teach the newcomer the proper way to build transitions, so he/she is free to build the railroad to suit their desires without infringing on the "widest curves, shallowest grades" foundation of model railroad construction. I fully agree--if you have the real estate to keep your curves level without compromising your minimum radius or ruling grade requirements, by all means do so. But the trains aren't going to fly off the track just because the track curves on a grade. 

Later, 

K


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## toddalin (Jan 4, 2008)

I have a curve on a grade that transitions to a straight (same grade) that does just what Greg infers.

Over time, with ground settlement, the curve starts to lean "this way and that." Some engines negotiate this with absolutely no problems whatsoever. But some (e.g., Aristo FA and U-boat) with more rigid and/or longer wheel bases have a tendency to derail just as Greg notes and I can physically see the wheels lift off the rails and drop off the track.

When it starts doing this, I know its time for re-leveling side to side.


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## kormsen (Oct 27, 2009)

on my last two layouts i built grades by trial and error. 
because of little space avayable i had to use curves and grades together. 
on the pic below you see on the right a descent of 8%, and on the left an ascent of 7% (the maximum that my single small locos could master with five cars), both made with R1, R2, R3 curves and straights. 
i did not have any problems with curves on grades. but i carefully watched the side to side level. 
for transitions i used two foot length. at each rail joiner 1%, plus each one foot long piece of rail bent upwards for 2 to 2.5%. 
that worked even at places, where the transitions were made of R1 curves. 

i should add, that i got only 4 wheeled locos then and that i don't run my trains fast. 
rolling stock were LGB, playmobil and DIYS. (none longer than a foot) 
.


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## Totalwrecker (Feb 26, 2009)

Dang! I think I've been out in the heat too much.. 

The only reasonably smooth transition that may cause a problem will be from flat to down. Too severe and the center axle will bear the weight and add a sharp curve and suffer a derailment... 

By using a more proper geometry you can rely on all the axles to steer the truck, of course if there's something called a floppy axle (strange concept) then yes I can see Gregs point of view, but a rigid truck should be fine. For me the proper geometry is to drop the inner rail, as I transition down into a curve's to super elevation so my outer most wheel (front outside side of curve) is guided into the curve. Those who insist on flat curves .... well sure makes realism harder....and you build in the problem as I see it. Narrow gaugers used super elevation. Look at pictures of The Clear Creek line in Colorado, You can see the lean. 

Greg, do you use those floppy axles? if yes then I see your frustration. 


The transition from flat to up will only lift the center axle and shouldn't pose a problem. 










John


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## Greg Elmassian (Jan 3, 2008)

EXACTLY John! Thanks! 

I was trying to talk about ONLY the transitions from flat to grade, and vice versa, not the curves on the (constant) grade. 

Flat to down will usually lift the lead axle into the air. If you are in the air on the curve, you can have problems. Actually the USAT floppy axle works better than the rigid 3 axle Aristo. 

up to flat the same. 

flat to up usually lifts the center axles and usually causes less derailments 

down to flat the same... 

Anyway, when you get wheels in the air and a curve, it can cause problems. 

I changed my layout to eliminate curves on the transitions. I can now run (as I said) 50 car trains up a 3.5% grade and down a 5.5% grade AND with low flange wheels. 

That is not bragging, it's to try to convey the difference it made in running on my layout. 

After studying the suspension systems (or lack thereof) and the way manufacturers have tried to accommodate track geometries that are far different from prototype, everything I have done makes a lot of sense, besides the physical proof. 

Regards, Greg


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## East Broad Top (Dec 29, 2007)

I was trying to talk about ONLY the transitions from flat to grade, and vice versa, not the curves on the (constant) grade. 
Alas, I believe that point--with which I completely agree--got overshadowed by your suggestion to simply avoid grades of any kind on curves (with which I don't agree). 

So far as superelevation on the narrow gauge goes, it may have been built in at first on some lines, but it certainly didn't last long in many cases. Track was just as prone to lean to the outside of the curve as inside after a few years of "deferred" (to be polite about it) maintenance. But that's what I love about narrow gauge. It makes my trackwork look prototypical.  I did find a photo of a superelevation track level from the 1850s, so the concept's been around from the earliest days of railroading. It's not necessarily limited to high-speed mainlines. 

Later, 

K


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