I’ve got some tank cars built in the 1950s which are probably 11,000 gallon. A consist of these cars, box, hoppers, and reefs (50-54 ft in real life) can successfully repeatedly go around a 13 in curve. Some of these cars are 7-7.5in. Could 33,000 gallon whale bellies can survive such a tight curve. What about 26,000 gallon? What is their length in inches?
TIA!
~Lee
Are you sure it is 13 inch curves and not 18 inch… 13 inch- that is super tight for HO…
3 X car length is a tight curve
4 X car length is a moderate curve
5 X car length is a broad curve
So for your 13" curve your and a tight curve, you would divide 13" by 3. SO you would be looking at a car length of 4…3 "… thats mpore of an N scale curve
There are several other post you can search for that can help you more
ratled
Yeah a 13" curve is much more appropriate for N-scale. I would say the longest HO cars I would realistically try to run on 13" curves would be the 26’ shorty and beer-can type cars.
However I would say more important than the car length is whether or not the couplers are body mounted or truck mounted. Lionel & LGB can get some huge cars around very tight curves because the couplers are mounted on the truck and follow the curvature of the rail. HO has many examples of this as well. Most of the old Tyco stuff was this way. They had a 62 foot whale belly tanker that could easily navigate 18" curves. It is a compromise of a “toy” look versus getting an operating layout into a given space.
The only place 13 inch would look appropriate would be in a siding, running very slow during switching ops. Other than that it’s way too tight for HO.
1950s cars? Maybe some old Mantua-Tyco with the Talgo, or truck mounted couplers, maybe even with the old loop and hook couplers. Some Mantua kits were assembled with the hook-loop couplers body mounted. Maybe Bakers? Yes, they could easily (scale 40’) go round 13" curves. Mantua and Flieschmann sometimes had 15" radius or even tighter curves in their sets.
13" appearance wise might only seem suitable for interurban railways, but perhaps the space limitations our available locations provides can force us to either use small radius curves and Snap Switches for a layout, or go to collecting stamps for a hobby.
Most - but not all - 40ft (6" in HO) cars can be made to go around 12" radius curves. They won’t do it at high speed, and very good trackwork is needed. It’s not a pretty sight, either. But it wasn’t unheard of for the prototype to force 40ft cars (but no larger) around 90ft radius curves at switching speeds. Of course, cars shorter than 40ft will work better. And the number of locomotive models that will work on that radius is pretty small.
In most known layouts using 12" curves, body mount couplers will work. However the underbody or center sill or body bolsters may need trimming to allow the trucks to rotate enough on the curves.
my thoughts, your choices
Fred W
Caveat: I model in HOj (1:80 scale) which has track geometry equivalent to North American HO.
I own several tank cars of various lengths. The only one that will track safely on a 330mm (13") radius curve is a standard JNR 4-wheeler, about 100mm over coupler faces. The longer bogie stock will clash end sills on anything much less than 450mm radius.
I don’t own any HO models of the humongous hotdogs on wheels that I see at local propane distributors’ sidings, but I doubt that one would make it around a 13 inch radius even uncoupled. The trucks would bind on the coupler pockets or center sills long before that.
IMHO, tight curves plus short cars is workable. Trying to run long cars on tight curves is an invitation to disaster. My 350mm radius coal hauling private railway is embargoed to anything bigger than an HO scale ore jimmy. That includes almost all my locomotives, all of my JNR bogie freight stock and all JNR passenger equipment. Six-wheel teakettles and four wheel cars are the limit. (I have 610mm radius curves on the JNR.)
Chuck (Modeling Central Japan in September, 1964)