ok, I plan making a climb of 2.5" (N scale) over about 2.5 meters (confused? thats 8 and a bit feet) at 2%, but I need to come DOWN that 2.5 inches MUCH faster than that to make my layout work. How steep is 'too' steep? 2', 3', 4'??? What are the consequences of bringing, say, a 4 carriage passenger consist behing a steam loco and tender down that grade in say 3'? I would expect that to be the longest consist on the layout, with most being 4-5 freight cars.
mate, a climb always is a descend as well. just depending on the way you look. however I won't go beyond 3%. when descending your trains will speed up. maybe too much for the next curve or switch. if you're running conventional dc you could divide that descending track into multiple section. add a small resistor to the first section (where the descend starts) to reducce voltage. add a bigger one to the second section to further reduce voltage and so on. that's one way to keep speed at a constant level unless you're correcting it on your power pack constantly. it's even easier with dcc. lot's of the newer decoders feature speed stabilization. whatever you decide to do always remember that one day you'll run your trains the other way round. then a 4% decend becomes a 4% climb.
I know more than one layout owner who designed 'one way' tracks that ended up being bi-directional in the end. I would work really hard to keep that 2% grade both ways.
Disisme - I suggest that you set up a length of track with the percentage of grade, both similar to what you think you might need on your layout and put a train on it to see how it handles. That way you can make adjustment(s) as you find needed without having to change everything on your pike! All it takes is a 100 inch, (8 ft. 4 in.) length of board and raise it up 2 to 2.5 inches on one end and you got it! Good luck! [ 10 May 2002, 14:43: Message edited by: Ironhorseman ]
along this subject, on my layout that I am planning I have a point to point line that is separate from the main line. I wanted to do a 4% incline, the length approaching 20 feet of run. I was going to run my new Kato NP RDC cars on it, as if it was a line to reach a mountain resort. I am doing a G shape layout, with a couple of 'tonsils'. This line would run against the wall to the top of the G which would be my "wow factor" mountain that people would see when they enter the room. Comments?
Well, you've conviced me, so I've done a bit of a redesign based upon keeping the descent within limits for a single engine loco and 5-6 freight cars (I like box cars!). I've hand drawn a prelim layout of the top deck, but it shows the through line on the bottom deck as well. The curve radius has been kept to 14", except 2 turns on the lower deck that are at 11". Its primarily a doulbe mainline with 2 dogbones (so 3 times around) with, obviously, a lot of up and down (think I stay at baseboard level for maybe 8' throughout!). Basically, the entry and egress from staging consists of a single line that runs right around the extemity of the layout, with the line only ever being 'flat' while it is on the lower level, The rest of that line (4' up each side and 8' along the front) is climbing or descending. This give me about 8' in each direction to get down and back up again with a small section where it is at the same level as the double mainline and transfers can take place. This will look like the express line for through traffic while 2 trains work the double mainline. I anticipate there being access on the lower layout, eventually, for around 70 full consists (all short, remember), so to add 'feeling' for anyone visitors watching, you can run a consist around that line, and stragiht back into staging, then run another, then another, etc, so it LOOKS like its a busy route. Now, all this is possible without DCC, of course, but it will make switching a LOT easier if I have it :>)
