Rhett, Our, (Danny and myself), experience is that 45" minimum mainline radius with 42" for passing siding is a good compromise. Allow about a physical 1/2" for on each side of the curve for the easement using the bent stick method as described by Dick Karnes and you will have few problems except for long wheelbase steam locomotives.
Bob Werre may correct me, but I believe that the Houston S Gaugers modules use either 42" and 45" or 45" and 48" radius and we have run all kinds of equipment on them. Billy Click On Nov 25, 2012, at 11:24 AM, rhettgraves wrote: > Jim, > > I agree. My question was aimed at the technical issue. I've always thought > the NMRA Recommended Practices were aimed at the technical minimum, but my HO > experience is different than the RP suggestion. With a 14' wide room and > wanting to leave about a foot behind the track for scenery, I've got about > three options: > > 1. One big 72" radius curve. With easements, this would push slightly past > the 12' diameter. I really don't like this, though. It'll look too much like > an oval. > > 2. Two similar curves connected by a straight. I feel like I'd need at least > 6' between the curves, so two 48" radius curves would be required. On one end > of the room I'll be forced to do this since the stairwell comes into the room > at the corner. The limiting factor here is not the appearance, but the > distance between the curve and the corner of the room (which comes out to > about 1/2 the radius). The less the distance here, the better. > > 3. Two dissimilar curves. As you suggest, I could connect something like a > 96" radius curve to a 48" curve. This would give me the one "photo curve", > but I need to know the technical minimum for the connecting curve. If the > NMRA RP is truly a minimum, a 90" curve connected to a 54" curve will work. > > I'll be employing #3 for one end of the room, but the technical minimum will > be employed on the end with the stairwell. > > My trains will be the Illinois Central's City of New Orleans and Panama > Limited. They won't pass through at track speed, but we're talking at least > 12 85' passenger cars... > > Thanks to all, > Rhett Graves >
