Hi guys, can anyone tell me what the ratio is for uphill grades. I know there is a formula that so many inches of rise within so many feet but I don't remember what it is ? I am using different grades on my layout and want to make sure that I'm doing it right.
Thanks, Chuck
A 2% grade is 2 inches rise over a 100 inch run. In inches and feet, that is approximately 2 inches over 8 feet, or 1 inch over 4 feet.
Richard
Thanks Richard for the tip. that will definitely help me.
Chuck
RideOnRoadA 2% grade is 2 inches rise over a 100 inch run. In inches and feet, that is approximately 2 inches over 8 feet, or 1 inch over 4 feet.
Further, you can't get away with an abrupt onset of the grade, or with an abrupt outfall from the rise and back to horizontal track. You need a vertical curve at each end, meaning there will be less room between them to attain the height differential you had wanted. Means you'll have to add about 18" more to your grade process for a 1% grade and double that for double the grade...your 2%.
selector Further, you can't get away with an abrupt onset of the grade, or with an abrupt outfall from the rise and back to horizontal track. You need a vertical curve at each end, meaning there will be less room between them to attain the height differential you had wanted. Means you'll have to add about 18" more to your grade process for a 1% grade and double that for double the grade...your 2%.
In total agreement with selector and I think the term for these transitions to and from a grade is easement. Some vertical easement will naturally occur, when you bend the sub-roadbed to the grade.
The higher the percentage of grade, the less cars your loco can haul up the grade. For my length of train and type of loco combination, I determined that a 2% grade should be my maximum. I determined this by finding that my original grade of 4% was too much, so I built a loop into this section of track to drop the grade to 2%. 2% works for me, your maximum grade may be more; or, less, dependent upon your personal likes/dislikes!
NP 2626 "Northern Pacific, really terrific"
Northern Pacific Railway Historical Association: http://www.nprha.org/
Hi,
Yup, I agree fully with all the previous posters. May I add........ "Messing" with grades on a layout is serious business as it will very much affect the trains' performance and your enjoyment of the finished product.
A two percent grade (to me) is max for a regular layout. Some folks will go 2 1/2 percent but there is a definite difference in the locos pulling power. Now for narrow gauge, logging and mining layouts, some will go up to 4 percent. But remember, the trains that run these grades are short and pulled by specialized locos built for that purpose.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
I used a 4 foot level and a 1/2 piece of plywood on top of my plywood and made mine that way. I also made sure it was level in between the four foot section so there was no dips to cause the usual uncoupling. I used spring clamps to adjust the risers and screwed them in place as I moved up the grade. Two Kato locos can pull about 60 weighted cars up mine with no trouble. I've been running trains for 6 years and haven't had any problems as of yet. Jim.
gondola1988 I used a 4 foot level and a 1/2 piece of plywood on top of my plywood and made mine that way. I also made sure it was level in between the four foot section so there was no dips to cause the usual uncoupling. I used spring clamps to adjust the risers and screwed them in place as I moved up the grade. Two Kato locos can pull about 60 weighted cars up mine with no trouble. I've been running trains for 6 years and haven't had any problems as of yet. Jim.
You can also tape that "sized" block to the level to check the grade anywhere along the run.
I like the "cookie-cutter" or spline approach to bend up into or over back to level for automatic vertical "easements"
Modeling B&O- Chessie Bob K. www.ssmrc.org
It doesnt have to be based on 100 feet. A 2 percent grade is 2 percent of the length that you are testing.
If the length of the layout is 24 feet, then a 2 percent grade is 24 x .02, or 0.48, or 1/2 foot over 24 feet. That would be approximately 6 inches over the 24 foot run.
Rich
Alton Junction
Grades? LION got a 17 on his algebra final.
LION worts knot about grades. Look: One track is here, the other track is up there. They have to be connected.
Here is this theory in operation or route of Broadway LION:
Locomotives and trains went up and down the hill, what do I care about percents.
Bought new subway cars, you would think that they would work as well as locomotives, bu no, for some reason they do not. So LION pulls out ramp builds helix:
You can see where the upper level used to join the lower level. A loop was cut out of Celotex and inserted between the two tracks to provide an easement.
But LION became dissatisfied with this, and wanted a four track main line, and so him pulled this out and built a four track helix.
And as long as him build SUBWAY TRAINS, and helix *is* a tunnel, him also decorated the inside of it.
There. Now you know all you knead to know about grades,
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
Jim, your system seems rather imprecise to me. A level is really only a tool for determining if a surface is level; or, plum. It won't tell you what your grade is; or, if the grade increases; or, decreases over it's length; however the fact that it is a short length of straight edge will help determine the later.
In the end, the fact that you are happy with how your trains operate over the grade is what is important! Determining grade is easy as per Ride on Road's post in this thread.
I have 2% grades almost continuously throughout my layout. As a check on the rise over run, it's 1/4" rise every 2 feet as a memory jogger as you go along. I have open grid construction with the crossbeams on 24" centers. I built risers to support the subroadbed. This made it easy to mark the risers and keep track of where I was in the slope. I used 1/2" ply because any thing less thick you'll possibly get some flexing of your subroadbed. If you use thinner plywood, you will need more cross supports (say at 16"o/c). But with 24" centers, you just mark your risers 1/2" higher or lower as you go along. Definitely have an easement as your operations will run better and it'll look nicer.
NP2626 gondola1988 I used a 4 foot level and a 1/2 piece of plywood on top of my plywood and made mine that way. I also made sure it was level in between the four foot section so there was no dips to cause the usual uncoupling. I used spring clamps to adjust the risers and screwed them in place as I moved up the grade. Two Kato locos can pull about 60 weighted cars up mine with no trouble. I've been running trains for 6 years and haven't had any problems as of yet. Jim. Jim, your system seems rather imprecise to me. A level is really only a tool for determining if a surface is level; or, plum. It won't tell you what your grade is; or, if the grade increases; or, decreases over it's length; however the fact that it is a short length of straight edge will help determine the later. In the end, the fact that you are happy with how your trains operate over the grade is what is important! Determining grade is easy as per Ride on Road's post in this thread.
You seem to have missed the point of utilizing a small 1/2" block with the 4ft level. 1/2" @ 48" is rather close to a 1% grade. A 1" block w/ the 4ft level = 2%. The poster uses a separate block then places the level, I will tape the sized block on the end of the level to check grade anywhere along the run. To be more accurate you need a transit and calculate the grade. This is done at my club to layout the grades across many lineal ft of straight and/ or curved track. for setting the roadbed on risers.
Just a comment on tolerances when laying out grades based on personal experience...
Anytime you're at 2% grade and above per your plan, it's actually more important to verify the grade works by operating on it than in relying on the tolerances of wood, cork, and whatever else you lay track on UNLESS you prototype just keeps adding multiple units until the train makes it up the hill or the grade is nothing but a tangent.
If you're anticipating or desiring operation with single locomotives on grades of 2% or more with curves, then best get out your equipment and run on it with the track down before you get it all scenicked, dirted-in, etc. You might find out there are small imperfections that can stall that locomotive every time.
I recently ran into that myself in a rather dicey way, despite years of experience laying track, digital level, rechecking my work, knew the equipment i was using, etc. Those little Blackstone C-19s have a very short wheelbase and you need every tire on the rail, especially when your two sets of center drivers are blind. I was right at 2.5% on a 20" r curve. I knew it was right at the limits of adhesion to try to run 2 car passenger trains or 4 car freights, but the first efforts after track was down were truly pitiful. I had room to "stretch" the grade, in fact knew to leave some slack, but my easement at the bottom turned into a particular challenge before it was all over.
I bring this up not to discourage precision in "civil engineering" -- no, you still start with that -- but to ensure against a common "model engineering" tendency - to squeeze in the min. curvature and max grade we possibly believe might operate. Well, that's all cool on paper, but until you engage in real world testing, operating at the limits of performance takes knowing exactly what you're doing -- or you go splat like those wingsuit flyers have been doing lately. Close isn't good enough in challenging gravity with a train.
And there's really no exact science to ensuring what you design will work when it's at the limits of adhesion anyway, as many home layout design all too frequently are. The ONLY way to be certain, if the grades are substantial and the curves anything less than very generous, is to operate it as you envisioned and designed is to test it in action with the equipment you'll be using.
After several lengthy tunning sessions, my ruling grade is what I designed it to be: difficult to get right the first time, but relaibly doable, especially with practice. And the sound is great! Which is a lot of the point when you get the DDE dialed in on these little sweethearts. Lots of stack bark.
Mike Lehman
Urbana, IL
tallcapt, I believe 1/4" over 2 feet is about a 1 percent grade, perhaps it was a typo.
floridaflyer tallcapt, I believe 1/4" over 2 feet is about a 1 percent grade, perhaps it was a typo.
Yeah, floridaflyer is right.
Maybe tallcapt meant 1/4" rise every 1 foot which would be a 2 percent grade.
Yep I did...needed more coffee before doing that math in public.
I figured the same thing, when the poster had that 1/2" "ply" and a 48" level (only 1%) , that could have messed us up. We were talking about 2% to begin with.