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Wye Turnouts

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  • Member since
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  • From: Pacific Northwest
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Wye Turnouts
Posted by corsiar on Tuesday, June 11, 2019 8:52 PM

Is it a bad idea to have main lines run through wye turnouts and or the diverging track of standard turnouts?

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Posted by Outsailing86 on Tuesday, June 11, 2019 9:02 PM

Sometimes you see it, but in the real world it means both routes have to slow down, but a turnout lets a train run full speed on the main

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Posted by MisterBeasley on Tuesday, June 11, 2019 9:14 PM

I have main lines running through the diverging paths of turnouts, and seldom have issues.  Of course, I run a model railroad, not a real one, and I am faced with spatial limits that real railroads would avoid.

I don't run my trains very fast, either, and I'm fussy about my trackwork.

It takes an iron man to play with a toy iron horse. 

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Posted by hon30critter on Tuesday, June 11, 2019 11:57 PM

corsiar
Is it a bad idea to have main lines run through wye turnouts and or the diverging track of standard turnouts?

Hi corsiar,

Unless you have unlimited space (and funds) modelling requires compromises. Do what you have to do to get the track plan that you want!

Having said that, sometimes sober second thought will reveal better alternatives. Play around with your track plan. Just don't do it forever. At some point you have to start laying track.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by snjroy on Wednesday, June 12, 2019 8:23 AM

Here are some things to consider: your rolling stock, speed, and turnout length. I run a lot of steam, with short turnouts, so I avoided wyes and turnouts for the main to minimize derailments and interuptions. I also avoided magnetic uncouplers for unwanted uncoupling (i used electromagnetic ones).

Simon

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Posted by BroadwayLion on Wednesday, June 12, 2019 8:40 AM

NYCT has many places where the main line takes what would otherwise appear to be the diverging route.

 

Take South Ferry for example. The Mane Lion used to run on the straight leg of the turnout into the old South Ferry Station.

NOW they built the new South Ferry Station and access to it is on what would appear to be a diverging route. Of course subway trains headding into the terminal are not moving very quickly so speed is not an issue.

 

What is at issue is the HOME SIGNAL. Green over Green is the expected main-line route, in this case the diverging route when looking at the switch poiunts, where as green over yellow indicated the route into the old station which would have been on the straight leg of the turnout.

 

Between Jay Street and Bergen Street, the Green over Green indication would send a train to the lower level of the Bergen Street station and on to the express tracks.

But the express tracks are no longer used, the (F) train must take Yellow over Yellow to access the ramp up to the upper level of the Bergen Street Station. Even though all trains take the ramp going up, it still remains the diverging route and not the main routing of this signal.

 

Yor timetable will tell you what is expected at each location.

On the Route of the Broadway LION, the number one track receives a Green over Yellow signal as it moves across the crossover to the number two track for its trip south.

On the NYCT the same Home Signal indicates Green over Green for the same movement.

Either way the train is moving across the diverging points of the switch.

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by floridaflyer on Wednesday, June 12, 2019 8:41 AM

I have an Atlas #6 with the divergent being the main. Have run 4-8-4's and 2-10-2s over it for 13 years, not one problem. 

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Posted by BroadwayLion on Wednesday, June 12, 2019 8:52 AM

 

Here is a "Y" switch on the main line of the IRT.

Green over Green moves the train to the left placing it on the express track.

 

The Yellow over Yellow moves the train to the right placing it on the local tracks.

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by NittanyLion on Wednesday, June 12, 2019 8:58 AM

There's also the matter of "why."

I mean, up in Point of Rocks MD, anything coming off/heading to the Metropolitan Sub from/to the Old Main Line must go through one to three divergent tracks.  Just the nature of a junction.

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Posted by RR_Mel on Wednesday, June 12, 2019 9:06 AM

I have a wye on my mainline and haven’t had any problems since the track was laid in 1990.  All my mainline turnouts are minimum Atlas Custom Line #6.
 
 
 
 
Mel
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
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Posted by corsiar on Wednesday, June 12, 2019 11:17 AM

Trying to duplicate this used on Sherman hill before the west side of the tunnel. Top track is main line 1. Middle track is main line 2. Bottom track is the diverging track. On my layout I am using the bottom track as a siding/access to the yard.

I will be running 6 axle diesels, 4-8-4 (844), and a big boy (4014) through.

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Posted by snjroy on Wednesday, June 12, 2019 3:29 PM

floridaflyer

I have an Atlas #6 with the divergent being the main. Have run 4-8-4's and 2-10-2s over it for 13 years, not one problem. 

 

Yes, I can see how that can work. I have quite a few Peco no. 4s on my layout, due to space limitations. The large steam will take them, but at low speeds only, including a brass Mikado. But based on experience from my previous layout, no. 4s will cause periodical derailments on high speeds with steam when taking the turn. Too often to my taste anyway.

Simon

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Posted by corsiar on Wednesday, June 12, 2019 5:34 PM
I would be using PECO code 55 #8 with their wye which they claim is a 24" radius and the #8 is a 36" radius.
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Posted by cuyama on Wednesday, June 12, 2019 5:48 PM

PECO N scale Code 55 turnouts are referred to by the manufacturer as Small, Medium, and Large because all have the same frog, about a #6. The difference is in the diverging curve: 12", 18", and 36" respectively. The C55 wye is also a #6 frog and about a 24" diverging radius.

There's no such thing as a PECO C55 "#8" or "#4"

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Posted by BroadwayLion on Thursday, June 13, 2019 9:25 AM

snjroy
But based on experience from my previous layout, no. 4s will cause periodical derailments on high speeds

 

RULE OF FUMB

Speed = 2x the number of the turn-out

Ergo a #4 turnout is limited to 8 mph.

#6 to 12 mph

#8 to 16 mph

#10 to 20 mph, which is standard for yards on a 1:1

#20 to 40 mph, which is a very fast switch. Faster than that and you will need moving frog points as well. as switch points.

 

As it is on the 1:1 so it is on the 1:87

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by SPSOT fan on Thursday, June 13, 2019 2:45 PM

If you talk to guys who work in 1:1 they will say they hate it when mains take the diverging route, because they have to slow down to avoid derailments. For that reason the real railroads don't often put the main through a diverging track.

I hae riden extensively on a 1:8 scale railroad were the main often goes through a diverging route and people don't slow down, and they don't have any issues from it. Based on that I would think the effects would be even more negligible on a 1:87 (or 1:160, etc) layout.

So the answer to the OPs question is if the OP want's to be super prototypical, installing wyes or routing mains through diverging routes may not be the best choice, but if the OP doesn't mind a minor inaccuracy (accually I'd say it's more of a compression) they will be able to fit much more sidings on their layout.

As a final side note, if you do put the main through a diverging route, requiring operators to slow down through such switches would certainly add some interest (and time) to operations!

Regards, Isaac

I model my railroad and you model yours! I model my way and you model yours!

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Posted by SeeYou190 on Thursday, June 13, 2019 4:12 PM

Model trains look great running through curves, so I use WYE turnouts anywhere I can, just because trains look better when they go through them.

.

-Kevin

.

Living the dream.

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