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 --- In [email protected], "raisinone" <raisinone@...> wrote: > > Rhett: > I think there are two separate issues here: technical and visual. On the > technical side, using spiral easements will ease cars through tight radius > curves: 30 - 33 - 36". They will run fine but visually they will still look > like they are going around a tight radius curve. What I have done is tried > to balance the two elements by using 48" radius curves with spiral easements > and going larger wherever possible. The only place I might shave on that is > on a (hopefully) somewhat hidden, very slow speed track for turning around > trains. > > I was taught years ago that every layout should have a "photo curve". The > gentleman who told me had a 70+" curve on a layout of minimum 42" radius > eased curves, but the views and photos in that spot were stunning. Again it > relates to technical what works reliably with full length passenger cars > versus visual - what has "the look" you are trying to capture. Generally > bigger is better, but that is something for you to decide, I've never found a > magic formula just opinions (like my own... <G>). > > As model railroaders, we are reminded over and over of the places we make > both small and large concessions to 12" to the foot railroads. Track > curvature certainly ranks right up there! > > Jim Kindraka > Plymouth, WI > > > --- In [email protected], "rhettgraves" <rcandamoonpie@> wrote: > > > > I'm trying to design a layout for a 14' wide room and I'd like to be able > > to operate 85' passenger cars. I know from my HO experience that 85' cars > > will go around a 30" radius curve. They don't look good doing it, but > > they'll go and go reliably. When I look at the NMRA RP-11, you technically > > need 40" radius curves in HO for 85' passenger cars. > > > > So my question is this: Do I really need the RP-11 54" radius curves for > > full-length S scale passenger cars? Or will a minimum radius of 42" > > (corresponding to my 30" HO experience) radius work? > > > > I'm trying to keep my minimum radius at 48" and go larger where I can, but > > with only 14' room width, it's hard... > > > > Thanks, > > Rhett Graves > > > ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/S-Scale/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/S-Scale/join (Yahoo! ID required) <*> To change settings via email: [email protected] [email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
