You aren't going to like this. Wider curves are the best curves. Body mounted couplers are the best mount. Purchasing top of the line train equipment in any scale is the best option. With all that said. I use, disclaimer and I don't expect you to. 15" radius curves as a minimum for my N scale yard tracks. 20" radius curves as the minimum for my main lines. I have one 24" radius curve on my mainline that trains run through and look amazing. Minimal overhang. I use #6 switches as my minimum. You won't find #4 switches on my main lines. Industrial switching...maybe. As far as what is the tightest radius curve you can use. Wrap a pieced of flex track around your little finger. What the heck!! I said gritting and clinching my teeth. I can only hope that helps. Take what you will from here and discard the rest. See signature.
Not sure body mount is best as body mounts swing the coupler farther from the center of the track on tight turns. I think the key is to have only truck mount or only body mount, but with truck mount you have an issue right behind the body-mounted loco. So it would be interesting to test the problematic locos with both a body-mounted car right behind the loco and compare that to a truck-mounted car.
Yes, body mount can be problematic for tight radius. Try running a SD90MAC on 9-3/4 pulling a truck mounted coupler. But, some like the prototypical look so damned if you do and damned if you don't.
There's no question the broader the curve, the better. This started out as a curiosity from building a T Trak module. Remembering how locomotives would not work on the train set track from Bachmann starters of the 80s [9" radius] to see which of my locomotives would behave on such a tight radius.
I'm with you 100% George. Having used the imperial system of measurement since first grade (wow that was 55 years ago) millimeters are as useless to me as kelvins. I always have to use the Convert program as well. So once I've run the numbers through convert, I can say I prefer to use a radius of 254 mm or larger
Having a pretty large layout and a pretty large assortment of locomotives and cars, I have 40"min curves on the mains and 18 in the yards, I do go as low as 15" on industry tracks, and there may be an occasional 12 inch radius here and there in the hidden staging area. That is for the S2's pulling a string of 40 foot box cars out into the yard.
For those that have the space, of course the twenty inch or better curves are grand. The best that I can manage are seventeen inch on the main line of one part of the pike, This is equivalent to just over a thirty one inch radius curve in HO. From my HO days, all of the books indicated that you could run almost anything on a thirty inch or greater curve. The books classified anything over thirty inch radius in HO as "broad" Despite that, I am not running anything larger than a Pacific or Mikado on those curves. The only six axle diesel that appears is an SD-7. All of the other diesels that I run are four axle. Everything tracks well on the seventeen inch curves. The full length passenger cars look tolerable. There is another part of the pike with thirteen and three quarters "main line" curves. That is the equivalent of just over twenty five inches in HO, which puts it into the "conventional" category (at least twenty four inch up to but not including thirty inches). It is in a back part of the pike, so I can get away with full length passenger cars as the overhang is not noticeable. Only one steam locomotive operates on it, a 2-8-0. Only one six axle diesel, a PA, operates on it and that occasionally. The usual is four axle diesels. Due to the location of the curves, you really do not see too much overhang on the full length passenger cars. The remaining part of the pike has thirteen and three quarter main line curves. The first iteration of it had nine and three quarter main line curves. I was running shorty passenger cars on it as well as freight cars fifty feet or less. The diesel power was four axle. The steam power was USRA 0-6-0 at the smallest and USRA heavy 2-8-2 at the largest. Those curves presented problems for the Mikados and Consolidateds. I went to eleven inch main line curves. That was better, but there were still enough derailments with the Mikados and Consolidateds to make it annoying. The final iteration with the thirteen and three quarter fixed everything. Oddly enough, eventually, I got rid of the Mikados and Consolidateds (with one exception) so likely I could go back to eleven inches as I am running mostly four axle diesels (except for two RSC-2s, which I switch into the roster only on occasion) and nothing larger than a ten-wheeler for steam. It seems that for an eight drivered steam locomotive, you should have at least a thirteen and one half inch radius curve. The one exception might be the MDC/Athearn 2-8-0 (I still have one of those) as both middle drivers are blind. Some of the curves on the industrial trackage is nine and three quarters with one seven inch. The RSC-2s actually will run on the seven inch curves. The trackage with the seven inch curve sees no cars longer than forty feet. When I was in high school and doing HO, the best that I could do was twenty four inches on the main line, which was classified as "conventional". I ran nothing larger than Pacifics and Mikados or four axle diesels. At the time, there were many shorty passenger cars out there, so I could run those. Yes, the broader, the better, but you can get away with less to accommodate your available space.
I'm not the only one here that can write an epistle. Well played Brokemoto. May I add? I guess I should start with "Know your limitations". To continue with if you want to "Play with trains" and we all do. Then tight radius curves and truck mounted couplers will be your cup of Tea. Well not mine but might be yours. I have a friend who operates an HO layout with the same radius curves I operate with in N Scale. He once said of mine, "I could switch the track over and run my HO trains on "More Track Rick's" railroad." He's right you know. May he Rest In Peace. Which leads me to the point of the day. Having started out in HO, myself, like others here. I switched over to N scale because the "Conventional" curves in HO were way to tight. In N Scale there are advantages that become obvious. Which isn't Metric!! I won't use metric, not going to happen. One of my pet peeves regarding Kato, anything and everything. I do like their products. You'll find them on my current mess of a layout. In N scale a 24" radius curve is the equivalent (not 100 percent accurate but works here) of a 48" radius curve in HO scale. 15" is 30" and so on. One of those advantages that become obvious. Know your limitations. What Rick, you didn't already cover this? One more thought. If you are going to run with the tighter radius curves then don't purchase a SD90Mac and expect it to look pretty going around the 9 3/4 radius curves. Same with a 4-8-4. Aiiyiiyii!! Not pretty. Not going to happen. Stick with the four (4) axle diesels and the 0-6-0's smoke belching, steam spewing stoves. Short 40 foot or even shorter versions of freight cars and those shrunk down passenger cars. In other words get real. Did I say that? That should cover it. If you get my drift.
I agree with what you said with the exception of the body mount couplers. My beef with them is that they increase the coupling distance between cars. I don't run my MT heavyweight passenger cars for that very reason. An N scale person would need to practice the sport of broad jumping to go from one car to the next. I am in favor of broad curves. In fact I am trying to get our Ntrak club to change from three foot corners (radii of 27, 25.5 and 24 inches) to four foot corners (radii of 39, 37.5 and 36 inches). If you think long passenger cars on 24 inch radius look amazing then the larger radii will knock your socks off. As for switches, Peco C55 large radius is my preferred with their medium switch used for industrial. I do have some Peco set track switches that appear to be and probably are, smaller than a #4. These I have saved for a trolley/traction line. The larger curves eat up space both in layout length as well as width. That may not be a biggie with Ntrak or a club layout but for the majority of home layouts, it can be a deal breaker.
I actually have no problem with the metric system and probably use it as much or more than I do the traditional system, in modeling. It's just that, once you get past 50, or so, millimeters, it's almost impossible to visualize that given length whereas it's easy to visualize the same length in inches. I know the metric system is theoretically marvy but it has its chinks, too. And yes, I know all about conversions and have for almost 60 years but it's a pain doing them while on a forum. The celsius temperature scale is another pet peeve of mine. Doug
The key to avoiding conversions, is to adopt the metric system already! Aren't we the last major industrialized nation still on the Imperial system? At least we have great company among the only other nations on the Imperial system: Myanmar and Liberia! And since most things in the US are dual-labeled, it would sure be simpler to go ahead and switch. Our military already has. We already purchase liters of many beverages. But it is interesting that the entire world is on a decidedly non-metric system for measuring time. We all agree that the standard unit of time is a second. While sub-second times are measured in milli-, micro- or nanoseconds, a minute is 6 decaseconds, and an hour is 3.6 kiloseconds. That makes a day 86.4 kiloseconds (or 89.401 ks if they insert a leap-second.) FYI, a kilosecond is 16.667 minutes (or 3 kS is 50 minutes.) And let's not even get into weeks, months or years (leap or not)! Even metric countries measure automobile speeds (or highway speed limits) in km/h, when 30 meters per second is 67.1 mph. I think I could (approximately) convert to meters per second more readily than to km/hr. And once you get off the earth, meters per second is already the standard unit of velocity. We'll leave nautical miles per hour (knots) out of it for now...
I can see it now.... Highway Patrol Officer: "Do you know how fast you where going?" Me: "76 sir" Highway Patrol Officer: "No sir you where going 122.3101 !!" Me "Say what ???? Highway Patrol Officer:"That's 122.3101 kph sir!"
I am 73 years old. With health conditions and age I figure I have maybe 7 years left on this planet. After that you all can do WTH ya want...
But it is broke! Our products have to be labeled in both imperial and metric if we want to be able to export them. Or we have to build two differing products (e.g. automobiles) for export and domestic markets, which diminishes economy of scale in production. Things we import are labelled in both, or custom labelled (at additional cost we pay for.) That is, unless we are importing/exporting from/to Myanmar or Liberia... Like I said, our military (and its suppliers) are already working in metric (all requirements and specifications are in metric.) Believe me, metric is much easier to use. We should have changed a long time ago, but the same, old, tired argument still keeps us at a disadvantage to 99% of the industrial world. Like that scene from On Golden Pond, keeping an (anatomical) foot in both worlds is all wet.
