My layout is still under construction and I'm using #4 and #5 Walthers code 83 turnouts plus some of the #7 curved ones. My minimum radius is 24". My freight cars are mostly 40 footers with a few 50 footers. Passenger cars are shorter in the 60-70' range. I use only steam engines and have several Spectrum 2-10-0's and 2-8-0's plus several brass 2-8-0's and 4-6-0's of various importers and prototypes. I run a Western Maryland 4-6-2 once in a while too. So far I've had no problems with anything on these small-frog turnouts.
Roger
Like you I've installed a bunch of curved turnouts. The number I've used is based strictly on the curve radius needed. #7's and #7.5's on my main line. I've laid the track so you can't even see a wiggle as the train cruises the main line.
#5's in my yard do not get along well with my multi-modal cars, they tend to scrape over the manual throws on one switch.
Now if I could just get back to the layout and finish the last few turnouts, switch machines, and controls around the passenger station!
Mark in Utah
Everyone, those are all good points. Thanks
Insofar as I have a standard frog number, #5 fills the bill. HOj cars up to 20 meters (250 actual mm long over end sills) and all the standard JNR steam locos (largest are 2-8-2's with geometry similar to HO USRA mikes) handle #5 turnouts without complaint.
One caveat - I hand-build my own specialwork, including short, curved switch points and very short straight sections at the frogs, so my included radii are almost certainly larger than standard.
I don't think hi-cubes, 85 foot passenger cars or ten-coupled steamers would be comfortable with #5 frogs, but I don't own any such and can't say for certain.
Chuck (modeling Central Japan in September, 1964 - on handbuilt specialwork)
Mark, the substitution radius for N. American #6 turnouts is just over 40", so they are good for curves in the higher ranges, say above, 36". That is why they work so darned well in yards...they allow a lot of movement of the bigger stuff. The #5.5 turnouts that EZ-Track and others offer are good for between 22" and 36"ish.
Like you, I elected to have only #8's on the main, although I had to massage some Shinohara #7.5 curved turnouts to get them to conform on my main...it was all I could get. Can't beat them #8's for smooooooth running, eh?
#5 turnouts are suitable for a switchyard, knowing that you'll get a fair amount of overhang as you go though it. You have to be careful using manual controls, as many cars will drag over the controls.
I use #6's on my "local" track, which is designed for 22" curves and shorter trains.
I use #8's on my "main line", which is designed for 26" or larger curves and long trains.
Tortoise switch machies used almost everywhere except in the yard.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
I apologize right away for declining to answer you directly, but I have no experience of the type you describe. However, if I may, could I ask why you don't just go with the #6 turnouts where you can. It may mean some juggling or re-design, but they will permit you to operate just about anything you can buy in HO. IOW, you will have leg room for future needs, and not be constrained by your vision today.
I know that the curves generally sold with EZ-Track of the 18" radius type are really 4.5ish, and they handle a lot of items that a simple #4 will not. So, you should anticipate that a true #5, especially of the non-European/British type curved divergent, will let you run much more, and even heavyweight passenger cars at yard speeds.
Does anybody here use #5 turnouts in HO scale? If you do how well do they perform? Do you have any problems switching long cars?