Although some people have done it, I haven't been able to get my Walthers / Rivarossi 60' cars with body mounted couplers to go around a 22" radius curve (which was the tightest curve on my last layout) when coupled to other cars, but IHC/Athearn/Rivarossi 70'-80' cars with talgo trucks did it with no problem, as did the old MDC 60' Harriman cars with talgos. In fact IIRC, Athearn, IHC, MDC and Rivarossi cars with talgo's are all designed to take 18" radius curves, but of course the larger the radius curve, the better they'll look.
If you're looking for heavyweight era cars, I would to with Athearn or MDC Harrimans. Both are easy to build and result in a good reliable car. Athearn fluted-side or Con-Cor smooth side 72' cars would work for streamliner era trains.
I dont do less than 28" for reliable. I had a AHM Obsveration that was like a foot long, weighed lighter than the paint used to color it and looked terrible on the sub 18" radiius at the time.
Here I am playing with big Heavyweights and thinking 31" is too small.
Nevin,
Are you looking for a minimum that's merely functional or do you want it to be functional AND look good doing it? R19" curves will work okay on 60'-70' passenger cars. However, it won't look very pretty doing it. The tighter the turn, the more you'll have to compensate track centers to avoid side swiping other cars and structures. Go with the largest curved radii that you can get away with.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
There is a just-issued Model Railroader "online-extra download" by Andy Sperando, "Track and coupler standards for passenger operations."
http://www.trains.com/mrr/default.aspx?c=a&id=1965
Andy's article packs a lot of wallop into 4-pages including prototype passenger facility track photos, suggested curvature standards, avoiding S-curves, using double-slip turnouts, proper use of magnetic couplers, and thorough instructions for the bent-stick curve easement technique.
Conemaugh Road & Traction circa 1956
Nevin, I have the Bachmann Spectrum passenger cars and they'll handle 22 inch curves all day long, but in your hidden staging yard I'd be more concerned with the turnouts. Ya know, come to think of it, I've never tried to run mine through my yard area which as the Peco medium (I think that equates to about a #4 turnout). I'll have to try that but I'll bet they'll derail. On my mainline the siding they usually sit on has Peco large radius turnouts.
Good luck!
JaRRell
Although I think 19 inches is pushing it for a full sized passenger car, it can be done with proper weighting and perfect track. Since this is a staging yard, I assume you have switches to deal with. As long as they are all # 5 or better and not located on those sharp curves, it should work. If the switch is coming out of the curve, I think you're going to spend a lot of time rerailing.
ndbprr wrote:This discussion keeps taking a turn that the originator did not ask about. He is interested in knowing of 60-70' passenger cars will negotiate a 19" radius and the answer is yes. That's why they are shorter as they date to an era when 18" was considered a mainline radius in HO. Results with 85' cars are irreleavent to the answer and confuse the issue. Done my rant now!
I disagree. The question was passenger cars negotiating curves in a hidden staging yard. A staging yard indicates turnouts to me and that throws a whole new problem into equation. If the question was just curves on a layout, that's different. A 70 foot car coming off a 19 inch curve into a number 4 turnout is problematic at best.
UP2CSX wrote:A staging yard indicates turnouts to me and that throws a whole new problem into equation. If the question was just curves on a layout, that's different. A 70 foot car coming off a 19 inch curve into a number 4 turnout is problematic at best.
A staging yard indicates turnouts to me and that throws a whole new problem into equation. If the question was just curves on a layout, that's different. A 70 foot car coming off a 19 inch curve into a number 4 turnout is problematic at best.
The combination of staging tracks, car length, turnout size, and curve radius is why I found the article referenced above to be useful. There are also two overhead photos of 80' passenger cars negotiating a 22" radius curve and a 32" radius curve.
A 70' car should be able to negotiate a 19" radius curve with #4 turnouts, but the overall track staging design will factor in, and; a 70' passenger car with a 19" curve radius may render the same scenario as illustrated in the article's two pictures.
What would be the minimum radius that 60 or 70 foot passenger car with kaddie couplers and 3 axle trucks could reliably go around without derailing
There is the original quote. Now continue your discussion about 85 footers if you want but it is irrelevant.
I offer this idea.
Buy several curves.. 90 degrees or flex track and create the radius you want to test your passenger car (WHATEVER LENGTH they are). Go smaller in that radius until you hit the point of not being able to stay on the track. You just found the minimum for that car.
Repeat the exercise with a engine coupled to your passenger car (Your longest one) and go smaller in radius until you find the failure.
Whatever the failure radius you have, add two inches to it and you should have a radius that will handle that passenger car.
What we really should do is plan for the really BIG equiptment and go large radius as possible. THAT is the key to reliable operation. Sometimes you just cannot have both the cake and icing.