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Minimum radius (not the same old question)

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Minimum radius (not the same old question)
Posted by carl425 on Monday, September 1, 2014 2:11 PM

I am including a wye on the layout to represent a junction with another railroad.  Trains will never run on this track.  Because of space constraints I'd like to use as tight a radius on the legs of the wye as possible.  We always talk about the radius at which trains won't operate properly or they look toy like.  How tight can a curve be before the track itself without a train looks bad?  I'm in HO and minimum running radius is 24".

A related question, anybody do anything special for a turnout that will never be thrown?

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Posted by ndbprr on Monday, September 1, 2014 2:46 PM
Why do you need to model the whole wye? What if the two leads disappeared behind buildings or scenery?
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Posted by angelob6660 on Monday, September 1, 2014 3:03 PM

Wouldn't running a 24" radius curve to tight, to run your equipment? I would prefer 28 or 30 on active track. 

I believe a 24" track will be fine on an inactive track.

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Posted by carl425 on Monday, September 1, 2014 3:41 PM

angelob6660
Wouldn't running a 24" radius curve to tight, to run your equipment?

My equipment runs fine on 24".  If I had the space, I also would prefer 30".

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Posted by skagitrailbird on Monday, September 1, 2014 3:52 PM

For the turnout that will never be thrown I would spike it in position.  Drill a small hole in the throwbar and insert a track nail or spike.

As for the radius I am only guessing but I think 15" is as far as I would go in that situation.  even better is the idea of having the legs hidden by buildings, etc.

Good luck!

Roger Johnson
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Posted by carl425 on Monday, September 1, 2014 4:01 PM

ndbprr
Why do you need to model the whole wye? What if the two leads disappeared behind buildings or scenery?

That's the plan.  The prototype wye I'm trying to represent goes off into the trees shortly after leaving the main.

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Posted by richhotrain on Monday, September 1, 2014 4:11 PM

I think that it is hard to make a wye give a toy-like appearance, especially if you are not running trains through it.

I have used #2 1/2 wyes on a 24" radius layout and #3 wyes on a 30" radius layout.

I don't know if there even is anything out there less than a #2 wye.

I agree with Roger that driving a spike through the throwbar to hold the wye in a fixed position is the way to go.

Rich 

Alton Junction

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Posted by ednadolski on Monday, September 1, 2014 4:48 PM

This is a very subjective question.  Best recommendation I have is, to build a quick mockup from some flextrack, put your rolling stock on it, and decide how it looks to you.

Another thought, sometimes you can use trees, structures, etc. as a bit of a viewblock to partially hide a very sharp-looking curve, and reduce the visual impact.

 

 

HTH,

Ed

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Posted by cowman on Monday, September 1, 2014 8:31 PM

If you can  hide the tail, you could do a scissors wye, which would put your two turnouts much closer together.

Just a thought.

Good luck,

Richard

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Posted by wabash2800 on Monday, September 1, 2014 8:47 PM

I like your thinking! Take a look at photos of real railroad track. Notice that the switches, and sometimes curves look much sharper than they are?  The prototype might be  No. 15 but it looks like a No. 6 to us. And if we scale out curves on the prototype, even though they look sharp to us, they would be way too big for our layout space. Yes, there is no need to make a wye take a lot of space if it's not going to be used. I'd say you could get by with 15" radius in HO. Now, here is something to know: curves look sharper when viewed from the outside. Consider that in what you are going to show of the wye. For example, when I look from the inside of a circle of track it doesn't look as sharp at it does from the outside looking in. This is something I remember from an NMRA Clinic.

Victor A. Baird

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Posted by carl425 on Tuesday, September 2, 2014 7:32 AM

wabash2800
Now, here is something to know: curves look sharper when viewed from the outside.

I'm pretty sure the effect you describe only applies to the trains, not the track.  When you view a train on too sharp of a curve from the outside, you see the outside rail sticking out from under the cars.  You also see the space between cars (which is already too large) being exaggerated.

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Posted by ACY Tom on Tuesday, September 2, 2014 10:47 PM

I have seen this done on a model layout.  The prototype location had a connecting track with a very sharp curve.  On the prototype, this curved track was regularly used; but for the modeler's purposes it was not really essential because it was just a connection to another carrier.  He laid out the track on a tight radius (18", I think) and banned steam locos and 6-motor diesels from this track.  Result:  The scene looks good and is easy for visitors to identify.  It's probably true that a broader curve would be preferable, but it simply wouldn't fit.

We do what we can do.  We come as close as possible to our goals.  We compromise where we must.

Tom   

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Posted by norpacguy on Wednesday, September 3, 2014 2:44 PM

If you are not using the wye in any way, why bother and use the space for something else.  As a minimum, I would think only one leg would do.  You could use your minimum radius and have a place to store cars.  Space permitting, use two legs and not the tail; you wouldn't even need the third turnout.

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Posted by Kyle on Wednesday, September 3, 2014 7:03 PM

You probably should solder the switch point to the rail to insure electrical reliability in addition to staking the switch in place with a track nail.  (see "Model a bulk transfer facility" on page 51 in the June 2014 issue of MRR).

As for an answer to "what radius looks to sharp" that is up to you and your situation. My suggestion is take a piece  of flex track and bend it until it looks good.  As long as it looks good, it will be fine.

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Posted by rrinker on Wednesday, September 3, 2014 7:19 PM

Take a look at what Tony Koester and Bill Darnaby have done with simulated interchanges. Rather than use abnormally tight radius curves (even though nothing will run on it) and having the wye meet within the confines of the layout, you have the main cut across your line's main, and you have, some distance away, one leg of the wye joining your main, using standard radius curves - the difference being the leg of the wye never joins the straight part of the main within your visible area - instad, it just heads that way, with th meeting point way beyond your backdrop and not visible. If you actually penetrate the backdrop you can stage cars on the wye lead and have a workign interchange.

                --Randy

 


Modeling the Reading Railroad in the 1950's

 

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Posted by wabash2800 on Friday, September 5, 2014 6:21 PM

carl425
 
No, the clinic and a resulting article were refering to the track which inluded an illustration. But yes, it would be noticable with a train also
 
 
wabash2800
Now, here is something to know: curves look sharper when viewed from the outside.

 

I'm pretty sure the effect you describe only applies to the trains, not the track.  When you view a train on too sharp of a curve from the outside, you see the outside rail sticking out from under the cars.  You also see the space between cars (which is already too large) being exaggerated.

 

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