# Feasible Operating Grades



## sherrard (Nov 10, 2014)

Any advice about proposed grades on the G Scale garden layout I’m about to start building would be welcome.

Originally it was my intention to limit grades to 2% to 2.50%, with a minimum radius of 6ft (approx 1800mm). However, the reality is that I think I may end up with grades of up to 3% to 3.5% in places with occasional radii of 5ft (approx 1500mm) or even 4ft. 

Desired train lengths are basically: 
(A) Bachman Spectrum steam outline loco with up to three cars,
(B) Aristocraft or USA Trains single diesel with up to seven or eight cars,
(C) Aristocraft or USA Trains multiple lash-up diesels (at least two, maybe three locos) with up to fifteen or so cars. 

All cars will probably be fitted with steel wheels. 

Can anyone advise if I’m likely to achieve the train consists stated above without stalling the trains, burning out loco motor(s), stripping gears or worse?

Many thanks.


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## Scottychaos (Jan 2, 2008)

1% - generally ok.
2% - really the practical limit for running semi-normal trains.

2% to 3% - dont do it unless you absolutely have to, and it will limit the trains you can run. trains will have to be quite a bit shorter than normal.

above 3% - I wouldn't do it, ever. 
you are NOT likely to achieve the train consists stated above without stalling the trains, burning out loco motor(s), stripping gears or worse..

If you end up with higher than 3%, IMO you should consider that plan "no good" and re-do the plan until you get them below 2%.

Scot


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## vsmith (Jan 2, 2008)

Come on Scott I had 5% grades on my old layout, if your running long prototypical modern mainline standard gauge consists then by all means *yes* you are correct BUT if your running short narrow gauge trains its not that huge an issue, it really depends on *what *you are doing and what your goals are, fast mainline action or twisty narrow gauge mountaineering 

Sherrard

You should be OK with 3-3.5% with those ratios but keep in mind that the more cars you pull and the steeper the grades the more wear your putting on your engines, and these days replacing worn gears can be a major headache, if you want to run long trains, try to keep the grades to a minimum under 3%, but if you can live with 3-4 car trains you can get a little more Colorado-ish with them. Scott is completely correct though that you should* try* to keep your grades to a minimum to help preserve your engines lifespan. As for engine pulling vs train lengths that's going to vary engine by engine, the best way is to experiment what each will easily pull over that grade and then hold to that, if its slows or hesitates, reduce a car and see what happens. I have have some engines that pulled like real champs, my home made F-40 pulled 4 Superliner cars up 5% grades around R1 curves!, and one or two that were absolutely beyond pathetic, one Buddy L loco couldn't even pull the weight of its own bobber caboose over my original indoor line's 5% grades.

Remember Aristo is dead! They ain't coming back, at least not in the way they once were. So any Aristo engine you purchase may have almost no ability to be repaired if you smoke the gears. A/C has very limited repair capability and if their are no spare parts I doubt you'll ever get it repaired.

Bachmann's latest incarnation of the 4-6-0 Annie has perhaps the best gearbox in LS today. Beware the 2-8-0 Connie unless someone has upgraded the gearbox to a "Barry's Big Train" drive. Also stay away from the tiny 2-6-0 Industrial loco with those grades, the Spectrum's C-19, 2-6-0 Mogul and the 4-4-0 REALLY need 8' to 10' diameter curves, but the Annie will run like a champ on even R1 curves (4' dia) 

FYI In LS we generally use DIAMETER not Radius, to distinguish curvature. 

Steel wheels certainly do help, if you have very deep pocket, ball bearing wheels are the very best, they reduce rolling resistance to almost nothing and eliminate binding thru curves.


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## Scottychaos (Jan 2, 2008)

vsmith said:


> Come on Scott I had 5% grades on my old layout, if your running long prototypical modern mainline standard gauge consists then by all means *yes* you are correct


Yes, I am correct..thank you for noticing! 
I based my reply on the kind of trains he said he wanted to run..



> BUT if your running short narrow gauge trains its not that huge an issue, it really depends on *what *you are doing and what your goals are, fast mainline action or twisty narrow gauge mountaineering


True..but I based my reply on the kind of trains he said he wanted to run..


Scot


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## jimtyp (Jan 2, 2008)

Sherrard, The rule of thumb I've heard in the past is 4% max, but try to keep grades as low as possible. It may depend on what you are running, as others have said. Some DCC decoders and other technologies compensate a bit - apply a bit more power uphill and less on the downhill so it doesn't race downhill.

-Jim


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## livesteam53 (Jan 4, 2008)

Tight curves and steep grades are very hard on your locomotives.
Keep the curves as large as you can.


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## eheading (Jan 5, 2008)

I have one grade on my railroad that is a little over 3% and has a 10' diameter curve on it. I have no problem pulling 20 cars up that grade with two Aristo diesel locomotives running in tandem. I have had no gear problems in 4-5 years of running this grade. Just a data point. I would not like the grade to be any steeper though.

Ed


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## mgilger (Feb 22, 2008)

Sherrard,
Going to 3-4% can be done if you have the horse power to overcome it. Your Bachmann probably would not handle it to well, even pulling 1 car, where your USA or Aristocraft's might do ok. 

I have several grades above 3% that my Aristo and USA diesels handle just fine, if I have the correct power on the consist. I can easily pull 25 cars through my entire layout if I use 2 of my SD-45's, were using a single, say RS-3 I might be limited to 7-8 cars. 

One of the interesting things to consider when you have larger grades is using helpers to get you up the hills. 

Regards,
Mark
*http://mmg-garden-rr.webs.com/*


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## East Broad Top (Dec 29, 2007)

For all practical purposes (and the trains you're describing) a grade of 3 - 3.5% will prove to be no problem at all. You can run a reasonable train up it with a reasonable locomotive without any ill effects. Yes, train length will be limited--just as it is on the prototype. You must take that into consideration. Also, you don't want to combine the steep grade _and_ sharp curve if you can at all avoid it, as the two compound each other. For the curves you're describing (6' radius and broader) you shouldn't have too much worry. If you start headed towards the 4' radius end, I'd make sure the grades on those tighter sections are flatter than elsewhere. 

Obviously "flatter" is better, but don't fret too much if things start to push into the 3 - 4% range. My dad's railroad has been in operation for coming up on 35 years, and has many stretches of 4% grades. We run all sorts of manufacturers' locomotives on those grades with no ill effects. He's got a stretch of track that varies from 5 - 8% which is either "helper district" or you must split your train to 4 cars maximum going up. Again--in many years with many manufacturers' trains, we've never had a failure that wouldn't have manifested itself on flatter railroads as well. Our trains are mechanical things, and they do have limits. Provided we operate within those confines, there's no reason not to expect reliable service.

Certainly for the narrow gauge trains you describe, you will have no troubles with the steeper grades. And 7 - 8-car trains with a USA or Aristo diesel should also be of no consequence on such grades. Such trains are similar in nature to what operate over my dad's railroad during an operating session. 

If you have trouble with the 3-loco/15-car trains you're describing, it won't be because of the grades, it'll be because of the curves. A train like that will quickly push to 30' or more in length. With that much train winding around 5' radius curves, you're going to introduce a lot of drag and increase the likelihood of "stringlining" where the train will derail on the apexes of the curve due to the excessive drag. Long trains like that look better on broader curves anyway, so if that's your plan, I'd probably shoot for curves of 8' radius or greater. Your eyes (and flanges) will thank you.

One caveat with steeper grades, though, is that you'll want a throttle system that is very controllable. Trains will slow down considerably going up the grade, then as soon as it crests, take off like a shot going down the other side of the grade. This will be true for pretty much all locomotives, regardless of how they're geared. (On my dad's line, you learn very quickly where the grade changes are, and learn to adjust the throttle accordingly.) You'll want a throttle system that allows you to carefully control the speed of the locomotive without a lot of fiddling or guesswork. 

The cool thing here is that many of the latest generation sound systems can read these changes in throttle setting relative to speed, and will adjust the sound in response. So, when you hit the base of a long, steep grade and bump the throttle up, you get a sharp "CHUFF CHUFF CHUFF" as it digs in and attacks the grade. At the top when you back off the throttle, the chuff becomes almost completely inaudible as the loco drifts slowly back down the other side. As you operate around the railroad, you actually seek out and work the grades, because it just sounds so friggin' cool!

Some 3rd-party control systems allow for "Back e-m-f" control, which is essentially cruise control for trains. If you wanted to go that route, it's a great way to deal with excessive changes in grade. I installed one system (Airwire) in one of dad's locos, and ran it up and back down the entire line (2000' round trip), encountering grades up to 8% along the way. With a 6-car train in tow, there wasn't so much as a minor perceptible change in speed along the entire trip. 

You're never going to go wrong with keeping your curves as broad as possible and your grades as shallow as possible. In all my years, I've never heard anyone say "Gee, I wish I used a tighter curve there." But I think we also tend to get caught up in keeping things as broad and flat as possible, and make compromises on our railroads that perhaps we might not have to have made otherwise. Since you know the types of trains you want to run, seek out other existing railroads with varying curve/grade conditions and see how your trains perform in those environments. If it's not to your liking, then you at least know what you don't want to do. 

Later,

K


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## Greg Elmassian (Jan 3, 2008)

I have a maximum of 3.4% running about 80 feet... I can pull a 50 car freight up it with 3 Aristo E8...

http://youtu.be/aYMt_c70oN8?list=UUUny9fLFoSuNCA_LzmXAUAA

Just put on more locos...

Greg


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