Working on a 2x8ft layout design that features one track crossing over another. The outer loop rises 20mm (0.75in) while the inner loop falls 20mm. This allows 40mm (1.5in) of clearance where the two tracks cross. The track length is about 3ft / 1m, giving about 2% grade up and 2% down, but it's almost all on a curve. Any problems with this arrangement? Will be running Marklin steamers on this layout with say, 10 two axle cars, or 4-6 four axle passenger cars. Here's the left end of the layout: The squares are 12", total width 24". Seems like this should be gentle enough for the trains I'm planning, but just wanted to check here. Thanks, Mike
Mike, 2% grade is about as steep as I would go (I've personally done 3% and been "disappointed"). Running through the rise in a curve will probably be a hard pull with the trains you're interested in as you'll be pulling trains that will wrap through most of the curve. My 2 cents, Mark
Worse?! I thought the Noch premade layouts had like, 5% grades to make their loop. Is the 2% grade that bad around a 10" radius curve? The only way to lower the grade is to lengthen the layout. How much more trouble is 2x5' modules than 2x4'?
Shorter cars will have a much better center of gravity and less likely to derail on a curve while being pulled up hill. Long passenger cars and long freight cars have terrible center of gravity going around tight radius corners... So the bigger the radius you can make, the better for keeping long rail cars on the track. -Jon
Mike, You can get the over and under on a 2x4' layout, and what you posted will work. Typically 2% is the maximum grade for a no holds barred layout. Yeah Noch and others will use 4%, but then you have to start limiting the length and type of trains as Jon pointed out. Typically curves are derated to 1.5% max due to lateral loading. It would help to try to get as much as possible of the grade on the straight sections of track. Personally, I found a 3x4' worked better than 2x4'. The extra space allowed flexibility for the grades I couldn't get with the 2' depth. Mark
Well, enlarging the layout will fix the problem, but I'm trying to resist the urge to make it bigger. 3x4' is 50% more area than 2x4', a significant increase. I can easily move a 2x4 module up and down my stairs - a 3' wide module takes a lot more effort. And so on. I'll set up some test ovals to see how well things work on a 2% gradient. Then see if I can add a little more elevation before the curve, or lengthen the run to reduce the grade to 1.5%. I'd probably choose 2x5' before 3x4', just to keep things a bit more manageable. Can I get away with < 40mm vertical separation? Mike
Mike, "<40mm" are you on the N scale line? NMRA standard for clearance from the top of rail is 30 and 32mm depending on era. In the past I've added 4 mm for bridge structure, roadbed, etc. I'm thinking this just got a bit easier. You're right about a 3' wide. I'm using 30" wide for my new layout as it's the largest size that will fit through all my doors. Mark
Okay, I made a test loop of Microtrains sectional track, using 220mm radius curves, which roughly match my track plan. I elevated the curves with 2% Woodland Scenics ramps, and ran some of my trains around the loop. A Marklin 4-6-2 steam locomotive could pull 6 passenger coaches up the grade, but not 7. If stopped mid-curve, it could not start pulling up again. Smaller steam locomotives could pull 5 coaches, but not 6. Longer coaches were harder to pull up than shorter ones. Smaller cars were easier to pull up the curve. The sectional track had a definite negative camber when set up on the Woodland Scenics ramps (do doubt due to the temporary nature of the test). On an actual layout, I would be sure to super-elevate the curves so the trains would lean in towards the center of the curve. All things considered, I was disappointed with the performance around the curve, and will go back to redesign the layout to reduce the gradient. This will probably be done by extending the layout and widening the radius of the curve. Goodbye to the 24" layout width. Thanks to all for your inputs. Mike
Rokuhan does make curved track that is super elevated in four radii or you can place a small bare wire under one edge of your track when you are laying it down on your layout. ruling grades on your layout, it is suggested it should be 2% or less on main lines and never more than 4%, and as you have demonstrated you loose tractive effort on a grade so pull less cars and adding a curve to the climb further reduces the number of cars that an engine can handle, on the grade.
