Longest rolling stock that I can use to make it around the curves before they derail or have major problems. I am not so familiar with the prototypical demensions on this, so I am asking the experts! Thanks to all in advance. Carl
Assuming you are modeling in HO scale, normally the longest rolling stock that will reliably function around 15" curves are 40-50 foot cars and smaller four-axle diesels, operating at low speeds. If you want to run modern equipment or passenger equipment, expect many derailments on 15" radius curves, if they will function at all.
Real-world railroad curves are much, much broader than what we deal with on model railroads. Even what model railroaders consider broad curves are very sharp by real-world standards. Something like a 15" curve would only be found in very tight industrial switching areas where trains have to go around existing buildings–and those areas would be inaccessible to most modern equipment.
Having run a test for my interurban conection, 40’ is the longest you can do in HO on a 15" R. You MIGHT get 1 50’ around the curve, but not a train. The problem is the coupler overhang, the limits of the couple swing, and 1 car pulling the other off the track.
I would not try to use a GP or RS. Just too long. See ‘coupler overhang’ above. Stick with S or SW types, 44T, 70T, or 6 driver steam (x-6-x).
FYI, I have run a 40’ box (and just 1 at a time) around a 9"R with a steeple cab for power. Very good track, well adjusted car, and very slow speed.
Phil
For general purposes an HO 18"R curve is considered sort of a bare minimum. Passenger cars like Walthers cars and some larger steam engines require 24"R to operate. At 15" you might be OK with short cars and truck-mounted “talgo” couplers (rather than body mounted ones) but you’re really limiting what you can do and what you can run by going with such sharp curves.
IIRC the sharpest US mainline curve works out to about 33"R in HO - and trains would be required to slow to 15-20 MPH to go thru that tight a curve. To go at 75 MPH a real train needs 6" of superelevation (the outide rail being higher than the inside rail in the curve by 6") and a 2-degree curvature minimum…which works out to about 30 FEET in HO scale !! [:O]
In 1923 Southern Pacific subsidiary Pacific Electric bought 300 40’10" flat cars capable of negotiating 46-foot radius curves (involving different linkage for the hand brakes). That’s just over 6 inches in HO scale.
Mark
Keep in mind too that if your tagline about modelling the 1970’s to the present is correct, the number of 40’ cars dropped off considerably during that time. Except for 40’ boxcars kept around for grain service into the ‘70’s, most cars would be 50’ or longer. Getting an SD-40-2 and a string of 55’ covered hoppers or 50-60’ boxcars to negotiate 15"R curves reliably might prove quite a challenge. If you were modelling 19th century railroading with small engines and 28-36’ long cars, or say a logging line with a two-truck Shay or Climax with short log cars, it might work a lot better.
[2c] Yep. Those two features don’t go well together unless you are using EMD SW-type switchers on a yard-work type of layout. However, you might have in mind modelling some old branch line of coal that was still operating a GP7 or something like this: http://www.railpictures.net/viewphoto.php?id=146348&nseq=13
Otherwise you may end up with a lot of this if you use late era hoppers/gondolas: http://www.railpictures.net/viewphoto.php?id=200275&nseq=10
Half a dozen answers saying the same thing. I will chime in for us small scalers. 15" R curves in N scale is pleeeeeeeeeeeeeenty. A consist of big 6 axles, SD70’s/90’s, Dash 9’s, well have no problem with 15 inch curve, nore any 73 foot center beam flats. I would imagine the 89 foot cars would work, but again like the other posts said it would look better on bigger curve. Just for comparisons, 15" R in HO is equivalant to about 109 foot curve, while N scale would be 200 foot curve. That post about working HO scale cars over 9 inch curve is amazing. Typically in N scale the minium radius curve for lokes is 9 3/4 inch curve. MR has had product reviews on an Atlas GP30 and Kato FP45, both worked 9 3/4 inch curve just fine. It all really comes down to what lokes you plan to use. I believe I read somewheres that a 50’ N scale car could go around 7inch rad curve, but I don’t see too many lokes going around that besides small thingers like MDT’s, 44 tonners, 0-4-0T and 0-6-0T switchers.
I think N scale is not the scale in this thread, but just what scale is the OP talking about has not yet been established unless I missed the detail somewhere above. It is assumed to be HO.
Thank you Everyone for your answers, and yes, I forgot to say that it is HO scale. I am going to be running 2 to 3 bay hoppers for “Sawdust and woodchip” operations, as well as some coal, a few gondolas and also some logging and materials made out of logs after processing. My short line is simple, just didn’t know what was the longest rolling stock I could run in case I started a “New business” on my RR. Thanks again for all of your assistance. All of my rolling stock right now is around the 40-50’ arena. Carl
If space is at a premium, you might consider doing a shelf layout. I have up and running right now the first stage of what will eventually be a fairly large layout. For now it’s an L-shaped along-the-wall layout using 16" shelving as ‘benchwork’. I’m using minumums of No.6 turnouts and 31"R curves (HO) so I can run pretty much anything…except around in circles !!
[swg]
Stix,Several years ago I was fooling around with some 15" curves(a real oddity-I was building a shay powered short line on a 4’x4’)…I manage to ease a Athearn SD40-2 around those curves but,it wasn’t a pretty sight…[tdn]
IF there were any cars behind that engine she would have derail 'em from the amount of overhang…[:O]
Stix makes a very good point. My final HO layout before going outside, “G” was an around the wall layout in our double car garage. One request of the major share holder was to park her car in the garage, “the rest of it’s yours,” she said. I traded in her Olds and bought her a Subaru and went to work.
I crossed the garage door with 1x4s bracketed to the door. I also designed an interlocking so the door couldn’t be opened while running trains; after a near catastrophe. The point is, with an around the walls layout you can have large curves and open space in the center.
Have fun, Rob