I have read all of the information I could find about prototype grades and model grades. I have read that 2% would be more than maximum for prototypes, and modelers can get away possibly with 3% and 4% grades (Hence Woodland Scenics making money on their grade kits.) My question here, is: Is there anyone out there who has any experiences with a 4% grade? Good or Bad. I understand that more than a 2% grade is sacrelig for prototype modelers, but I intend to use a 4% grade in my layout if I end up feeling I can get away with it, and my trains will likely all be less than 10 cars or so. Any success or disaster stories are very welcome. Thanks, Scott
Prototype railroads usually max out at 2.2%, but this is really steep and often requires helper service to make it over. My advice for you is this: unless track at different levels must be connected or crossed over, avoid steep grades of ANY type. They are often too much of a hassle, especially in small scales like n. Here's a tip I heard somewhere; don't know if it's 100% true, but here goes: Let's say a loco pulls 20 cars. for every 1% of grade, it loses 50% of its pulling power. so at 1%, it pulls 10. At 2% it pulls 5. At 3% it pulls about 2 or 3, and at 4% it will result in a struggle for any more than 1 car. However, some engines ( some with traction tires) are better at hauling up grades, so I guess it all depends on what locos you use. But if you can, try to reduce it to a 2% grade.
Scott, it all depends on what type of trains you plan on running. An ABBA lash-up of F7s probably would be fine with 20-30 cars on a 4% grade. However, a Bachmann Spectrum 2-8-0 might have a problem with 8-10 cars on 4%. A Mogul with 5 Athearn Overland passenger cars would be straining, especially if the grade is curved. However, if you like running double-headed steam, maybe with one or two pushers at the rear, I'd say go for it. I have a tape showing the Maine Central running a combination of four Mikados and Consolidations, two pulling and two pushing, a string of 24 cars in the late 40s, up a 3.8% grade on the Mountain Division through Crawford Notch, New Hampshire. So there usually is a prototype for whatever you want to run.
As of right now, I have an HO Con-Cor Aerotrain with 3 cars. Also, I am awaiting an F7 ABA locomotive setup with Freight cars to be determined. I still have a 4-4-0 engine with 4 cars and a caboose that I may run as a tourist railroad also. It just seems very difficult even in my proposed around the room layout (12'x10' room) to do much with a 2% grade. Of course I'm sure you have all heard this before and I apologize for being the uber noob about this. I was just trying to see if there were any 4% grade success stories out there.
Scott, what you list should have no problem with a 4% grade. Just don't expect to run 30-40 car freights behind the F7s without some hesitation or stalling.
Scott, could you share your layout design with us? Maybe 9 times out of 10, there's usually a solution that eliminates steep grades and sharp curves, it's just not always easy to see. Also, if calculating tractive effort is of interest, here's a formula posted a while back by member rtroop.
Thanks guys. Right now, I have my benchwork pretty much designed, but I have about 3 or 4 track layouts I have drawn in RTS, but I really don't like any of them. I have attached the last layout I was playing around with. I am not really completely attached to anything I have done here, and I know I need a yard, but have no idea where to start one. I want to add some grade to it and perhaps a tunnel through a mountain somewhere, but I am stuck at this point. I have not built this benchwork as of yet, that will be next weekend or the weekend after. The benchwork will be plywood covered in 2" "pink stuff" foam board. P.S. I will try to do the math when I'm not as tired as I am right now, lol. Thanks, Scott
On the vakues, does the efforts change at all if a loco is pushing?Trainweight is still the same, but the effort is being applied in a different place.
Thanks for sharing the plan Scott. What I see, the direction you're going right now you dont really have the need for a practical grade, so throwing in a 4%er some where, just to have a grade is something I would highly re-consider. Something you might be able to do is a twice around over-under. I assume the blue section is the lift out, or duck under access point, so let's keep that at zero elevation. We start going to the right, counter clockwise, and we climb ever so gradually until we reach about 3" in elevation at the 12 o'clock position of the room. At that point, we start to come back down, until we cross the access point again at zero elevation. But we dont connect back up with the starting point yet, instead we continue to descend until we're back at the 12 o'clock position, only this time we're at something like negative 3" elevation. At this point, we'll pass under the first track, which will give you a great opportunity for a mountain bridge and/or tunnel scene. It's now that we begin to climb again until we reach the access point for the second time, finally reconnecting with our starting point. Raising to 3" and back in one loop of this size will put your grade under 2%. This would require a little wider benchwork than you have shown. I'd probably make it 2-2.5 feet deep all the way around and extend your major scenes (large town, maybe the mountains) out to 3 or 3.5 if you keep the tracks toward the front for easy reaching. You could also then include some hidden staging under the mountains as well.
I had a 3% grade along a winding curve, and could get about 5 cars max. behind a gp38 in N Scale. I have since torn that layout out and am starting fresh with much less grades. You may have some trouble pulling those 10 cars, unless you have an MU pulling the train.
The ONLY place I have trouble with my trackwork is on curves on a grade! Best to keep grades as small a possible and curves as wide as possible.
Mark, I may be missing something, but on your plan would the City, with its passing siding and team track, be on a grade? If so, this would put it above, yet close to the Industry yard, which might cause a crowding problem with building placement and scenery on both levels.
First let me say.... WOW!!!!!!!!. and Thank You!!!!! Mark, that is the most amazing thing I have ever seen. You just took my layout and incorporated everything I have ever imagined for it. I did not have the forethought or the design skill to do that. I do actually have some benchwork drawings that are closer to that than what I posted, so it should be no issue for me to do that. You were right on point about my liftout section, that is the section. If I may ask, what did you use to draw that layout? It looks much more detailed than RTS software I was using. I'll tell you one thing. I'm pretty sure that my layout will look very close to that and not much like I have drawn out, lol. Very good work. Thanks, Scott
Your welcome Scott. I used XtrkCad for all my layout designing. The rendering may appear more detailed than what RTS renders, but really as far as laying track, most planning software is in the same ballpark. Some more things about the design, I designed it with N Scale track in 1/2 the space. The minimum radius I put is 13.75" for N Scale, so that makes it about 25" for HO scale. Also, as Hytec pointed out, there will be little room for anything larger than maybe a signal tower between the two mainlines through the City/Industrial district, however you can place building flats against the wall and maybe have room for 2-3 buildings in the corner as well as one or two industries between the yard and edge of the benchwork. I would only raise the bridge line half of the absolute minimum height required to clear a train on the tunnel line, and respectively lower the tunnel line the other half of that height. I'd also keep all stubs level from the point of diverging off the mainline.
Mark, What type of track pieces would make up that crossover area at the bottom? Would it be 4 turnouts and a x type piece, or do they make a piece like that in atlas track? Thanks, Scott
That's called a double crossover, or more specifically a scissors double crossover. A quick Google search shows that Walthers makes one in HO Scale, but you can probably find a few different brands as well.
This is my best effort to plagiarize and copy what Mark drew out for me. I haven't had time to figure out how to use XtrkCad yet, so I did it in RTS 10. I haven't figured out the elevation part of the program yet. I figured out a double crossover with some #6 turnouts and a 19 degree crossover piece.
Flash Wave, there is no practical difference between pushing a train and towing it, but I did find that my smallish Proto 2000 USRA 0-6-0 was better shoving cars up my substantial first layout grade than pulling. Not sure why, but perhaps weight distribution had something to do with it. Maybe the first set of drivers had a bit more weight on them than the last...dunno. However, let's assume there is no difference in any one locomotive of any type. What you are likely to experience by shoving, especially if the loco turns out to be able to shove 10 or more cars up a 3% grade, is that the limiting factor becomes the couplers. They may deflect and uncouple and/or cause one or more cars to jump out of the rails, especially nearest the engine.
It's interesting you mention couplers, I had forgotten, but the same physics are used in 1:1 Trackmobiles to increase tractive effor. I believe they lift the knuckle to push down on the front of the TM and get more bite into the rail for their weight. On track plans: Good job on dumping the Double Slip/scisor. I'll vouch for them as they're needed,but fotr crossovers, 4 6s and a diamond is all one needs.
