I am designing a passenger yard and wondered what everyone thought of the diiference in operation for the #8 vs. #6 turnout. I plan to use all sizes of locomotived and passenger cars and was curious whether the operational performance is worth the additonal room required for the larger turnout.
The Issue is Normally the Space Used...BUT Hi: The issue comparitively is the amount of linear space occuppied by larger numbered turnouts than those that diverge more sharply. Yards, having multiple concentrations of diverging routings, are where this is most apparent. Unfortunately, model railroaders, as you are aware, are not making an economic profit out going railroading. Hence, our space is more limited than the real RR. The result is that model pikes tend to concentrate small numbered (i.e. relatively more rapidly diverging) turnouts in yards that are never found in a real world passenger car terminal area. That's because the relatively long passenger cars with tight lock couplings, are more likely to derail on this sharply diverging trackage. In the process they will close down other busy operations since trackage being used to switch cars, receive incoming trains, and dispatch outbound trains will be effected. From a modelers point of view, most make trade offs on our pikes in order to deal with our lack of space. We can live with quick "five finger" cleanups of derailments, not available to the Erie, NYC, et al. Now from an appearance point of view, the bigger the switch number , and the less sharp the diverging angle through the frog, the better the whole thing looks. By now you must have noticed how unreal the overhang of passenger cars and locomotives operating on 2 feet or so radius, track curvature appears. If you wish to have better looking terminals, and all things are equal with regard to switch quality, then the #8s are the way to go. IF, that is, you have the layout pike mileage to spare for them. Good-Luck, PJB
As PJB indicated, space considerations will play a major roll in whether you opt for #6s or #8s...not just their operational differences (which will lean in a barely noticeable and often debated way toward the larger turnouts). If you plan to run passenger trains that are X number of cars long and can comfortably park all the cars in a single train on yard tracks accessed through #8 turnouts, then by all means, stick with the larger turnouts because of their better appearance. If, however, you need every inch you can manage to squeeze in the bare minimum of cars you want to run in a passenger train, then opt for the #6s, because the difference in operational reliability, while present, is miniscule. Sometimes, a workable compromise is to place #8s at either end of the arrival-departure track, but use space saving #6s for accessing the various boarding, maintenance, or storage tracks where passenger cars might be spotted. When moving through #6 turnouts for those secondary tracks, the cars are being pushed/pulled more slowly than through the #8s off the mainline on to an arrival-departure track, so the operational reliability issue becomes a little less critical. Additionally, it may be helpful to make all tracks for passenger car spotting single ended except the arrival departure track which would have turnouts at both ends.
The geometry of turnout construction, and the rail size, is another factor. In N scale I had no problems with Peco No. 6's. No. 8's made it look better, but I had some space constraints on that layout, now gone. Off-brand No.6's marketed by many companies were a disaster. These were the type with the solenoid mounted on the side of the tracks--cheap, and a disaster for passenger cars. Of course, my track-laying back then was probably a disaster by itself. I've had very few problems with Atlas C55 No. 7s on the present road. Longer turnouts look better. As Dave pointed out, I've seen very little operational difference with good quality turnouts.
My first layout was all built with snap switches and #4's when I was in my teens. They limited me from using longer cars and loco's. I remember having a crossover made of 2ea #4's, and my roundhouse bulkhead flatcars would pick up their outside wheels crossing over it. Since then I have used #6's everywhere except on some short industrial spurs. For the re-do I am planning, I may go with some #8's for mainline passing sidings. Larger raduis's and turnouts will always look better IMO, just if you have the space....
Thanks everyone I have about 15-17 feet available for the passenger yard and terminal so I think I will use 8s on the passenger rail and 6s for mail and express lanes.
