i have notice that layout with steep grades is a no no
in laymans terms how steep is steep and how do you works it out in scale ie 2% 3% 5% is a killer and I have to ask what can happen if it is to steep dont just tell me it will stop does it were the motor out???
found this in a early post
No more steep grades. By “steep”, I mean anything over 2 percent. My last layout had a few 5% killers. On the new layout, I was going to limit myself to 3%. I quickly found out
done it again thanks for looking and feed back
itsback
Steep depends on what you can stand and what the locos can stand, given what you make them pull. Many modelers will tell you that grades over 3.5% look unrealistic, and that they will strain your capacity for “tonnage” over the grade, unless you team up locos. Unless they were using special tank and geared locomotives with a lot of weight over the drivers, grades in the real world are kept down to about 2% or less.
The trouble is that the lower the grade, the longer it takes for your trains to get to the height that you set for your trackplan. A 45 deg angle slope would be 50%, and super for getting up to another level to, say, a mine, in a hurry. But tell that to your locomotives. Instead, you will have to take about 160" of space to raise your track and trains enough to give them the minimum 3.5" of clearance over nether track at a grade of about 2%, plus or minus.
Grades, regardless of where they are, no matter the scale, no matter the purpose, are the same from grade-to-grade. A 5% grade on your local highway is the same pitch, and will take the same distance to rise a given height, as a 5% grade on your railroad.
A 2.5% grade in HO is the same as in On30. However, you will have to have a LONGER grade in On30 to get the required minimum passover clearance for that scale as you would in the smaller HO with its required 3.5" clearance for tracks that cross over each other.
Is this helping?
Steep is in the eyes of the beholder, within limits.
First off, what did your chosen prototype have for grades? Some railroads were lucky enough to build with a profile like a pancake, and considered 1% a major grade. Others, faced with vertical scenery, found it impossible to avoid much steeper grades. The steepest mainline grade in Japan, 68/1000 (6.8%) was originally operated with rack locomotives. When it was rebuilt to be operated by adhesion the curves were straightened, but the grade remained 6.8%. (A four-car EMU set wouldn’t have been able to descend it without a possible runaway problem, so two heavyweight, low-geared Co-Co motors were coupled to the front end as braking helpers.)
Second, what can your locomotives handle? Any grade dramatically reduces a given loco’s ability to pull cars. Since our sidings are almost always shorter than the prototype’s, this may be more of a blessing than a problem. Having a helper district makes real railroads very unhappy, but the increased operating interest on a model railroad may be a plus. Think of the fun of running the way SP did over Tehachapi and Donner Pass - four AC 4-8-8-2’s, two on the head end and two 2/3 of the way to the caboose. (Made for lots of extra switching at Roseville and Bakersfield.)
Third, is the track run one way, or two ways? There are some horrendous grades that are run downhill only. (UP through Weber Canyon had one section where the upgrade track wandered off to the north to keep the total grade down. The more-or-less parallel downgrade track was a lot straighter, and a lot steeper.)
On my layout the ruling grade is 30/1000 (3%), because I’m modeling a prototype that had 2.5% grades and ran trains half again longer than my sidings will accommodate. One purely downgrade track, thankfully hidden from view, is an 8% downgrade. My locos can hold their trains back, and nothing will ever have to climb it.
In the final analysis, how steep your grades will be is an i
selector…
I believe a 45 degree slope is a 100% grade!
Hence, a 90 degree “slope” is 0% grade… no forward lateral travel!
Putting words in the mouth of Wiley coyote as he finds himself on a 90 degree slope - “It’s all down hill from here!”
[:D]
Read about Cog Railways.
Check out how the boiler is mounted on the little Mt. Washington Cog Railway’s steam locomotive.
(click on highlighted words for links)
The grade percentage can go over 100% (in theory, I think not in practice). A 0% grade is flat, 100% is 45 degrees, straight up would be infinity% (dividing by 0), staight down would be negative infinity. For our purposes thinking of the angle is not very useful. It is hard to measure the small angles we are concerned with accurately. Grade (percentage) is rise divided by run( times 100 to get to percent). That you can measure pretty easily.
You are correct, and I was up way past my bedtime. [:I]
Thanks for catching my error.
-Crandell
How steep is too steep?
When your locomotive can’t haul the train it’s pulling up the grade, then it’s too steep.
I have 2 grades on my mainline that exceed 3.5%. This was out of necessity due to lack of space. Do I regret using a steep grade? No, I don’t.
I don’t have space for really nice long trains so I don’t have to worry about not being able to get the train up the hill. My BB SD40-2 can haul 30 freight cars up these grades by itself. Yet, my IHC 4-6-2 can only pull 5 Athearn passenger cars up the same grade.
I have seen a a track plan in MR magazine that used 3.5% grades which is where I got the basis for my track plan.
Play with various grades for your locomotives. See what they can & cannot do.
This way you can find our what is too steep & what isn’t
Gordon
I love the MT Washington Cog train. I’ve only been up it once, but I plan on going again this summer with my son. on Jacob’s Ladder, the pitch is so steep on Jacob’s Ladder, that one end of the passenger car is 14’ higher than the other end! The average grade is 25% but on Jacob’s Ladder its 37.4%!
Ply plans are to scratch build a Gscale Mt Washington cog in my back yard. I hope i get to start on it before i get too old to see.
I have some video of my trip that i would be willing to edit and send anyone on DVD if they are interested. just email me, its already on DVD, but it can be edited a bit more if wanted.
There is another web site that has more info on the MT wash.
http://www.cog-railway.com/
an HO cog would be extremley cool i think.
as far as i am concerned, I have taken an old Mantua 040 and had it running and then lifted the board it was running on to different pitches, it wasnt pulling anything, but I was able to lift it quite high before there was any issues, infact it tipped over as it traversed the curve before it had problems climbing.
Kevin