A surprisingly basic N Scale question about curve radii

[wm3798]

The return loops behind the paper mill were both 15", as well as buried in a lift out mountain, both were on grades to enable one to cross over the other, c55 with a bit of superelevation.  The tunnels concealed the "model railroadiness" of the over/under tight curving tracks, and also masked the unpleasant aesthetics of longer cars white-knuckling their way through the turns.







Because I was fanatical about quality control during that part of the build, it was one of the most operationally reliable parts of the layout.

The Thomas Sub track had the steeper climb, but traffic was mostly hoppers and 4 axle power, with occasional 60' hi cubes for charcoal service.  The Connellsville line managed long cars jus fine, but only with truck mounted couplers to manage the wide swing.  Being 15 years ago, that was pretty much what was available, so the auto racks and 89' parts cars did fine.

So, as long as you're thoughtful at installation, and don't stretch the limits of your rolling stock, you should be fine.
Lee

[jagged ben]

The Atlas 89s are the constraining factor for me too, and that could probably be solved if you can figure out how to get a longer shank coupler into them. 

[randgust]

After a lot of testing, rerailing and head-banging in comparison to MT, Trainworx, N scale kits, BLI, all piggyback flats... Even old Con-Cor door stops and lightweight Trix....

I simply resold them on FeePay.   I never beat it.   By the time you'd grind off everything under there to put in a longer shank you've pretty much ruined a beautiful car.  It's probably the only 89' that actually couples TOO closely.   The reason for the stringline is the distance of the coupler mount pivot away from the bolster center and coupler shank side swing, not just body mount issue.  And it's the only car I've ever had like that.

The other comment is that 13-15" radius looks pretty reasonable if you are INSIDE the curve viewing it, and a whole lot less reasonable if you are OUTSIDE the curve viewing it.  It's also a factor of viewing height.   My viewing height is a pretty consistent 52".

[bman]

So on my old apt layout with Atlas code 55 13.75" and 12.5"  radius curves with a bit of super elevation I alternated truck mounted Microtrains 89' flats between Atlas, BLMA, and Athearn 89' flats with body mounted couplers. I beleive it was mostly the Atlas flats that caused problems though. This mostly fixed any issues due to the tight curves and body mounted couplers on longer cars. The only time issues arose is when I cranked up the throttle and "went plaid."  Did it look pretty? Nope! Was I able to run a 7-8' long TOFC train along one wall in my sleeping quarters? Yes. Yes I was.