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Yard Track Spacing and Radius...

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Posted by 7j43k on Wednesday, August 18, 2021 8:20 PM

Overmod

 

 
7j43k
And that is because........

 

1) They are too long;

They are aluminum, and can be cut to length in under a minute.  Filing the edges of the cut smooth might take weeks, of course.

2) they can't be subdivided to shorter segments;

See above.

3) they lack any transition from a 'regular' switch into the small curve segment; and 4) they likewise lack any transition from the short curve back to tangent.

Because these curves are so short, there is no room to have an easement (transition).  In addition, it would be wise to use a fairly wide radius curve, so as to lessen the stress on backing movements through the switches.  And this also lessens both the need for and the possibility to make an easement (transition).

The real problem with putting in these micro segments of curved track is to not have a kink at either end.  To that end, it would be wise to solder a length of flex to the diverging track, and bend it to shape in place.  That should eliminate the kinking possibility.

 

A gauge facilitating laying the small curves involved here would have to fulfill all four of these, whereas the ones pictured can't do any. 

 

Done.

 

Ed

 

 

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Posted by Overmod on Wednesday, August 18, 2021 7:36 PM

cuyama
One could do this for one specific combination of turnouts, radius, etc., but it's not something that is one-size-fits-all. 

Yes, and the current situation (involving the stock #6s rotated to a steeper angle but preserving a given track spacing) can be used as the example.

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Posted by cuyama on Wednesday, August 18, 2021 7:31 PM

Overmod
I suspect cuyama could produce a template comparable to the transition spiral in MR that could be printed off, cut in thin sheet or whatever, and used to set this track by track.

One could do this for one specific combination of turnouts, radius, etc., but it's not something that is one-size-fits-all. 

Of course, if one chooses not to go to the trouble of laying this out with flex, one could forgo the small increase in yard body track length and just use the stock turnout angles.

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Posted by Overmod on Wednesday, August 18, 2021 7:00 PM

7j43k
And that is because........

1) They are too long; 2) they can't be subdivided to shorter segments; 3) they lack any transition from a 'regular' switch into the small curve segment; and 4) they likewise lack any transition from the short curve back to tangent.

A gauge facilitating laying the small curves involved here would have to fulfill all four of these, whereas the ones pictured can't do any.

(If there's anyone who knows where to find a single gauge that does what's needed, I'd expect one of the Eds would be the one to know...)

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Posted by 7j43k on Wednesday, August 18, 2021 6:55 PM

Overmod

 

 
7j43k
Comes in an assortment of radii and lengths.

 

Ed, those are worthless for the short curves and their transitions that are being described here.  

 

 

And that is because........

 

Ed

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Posted by Overmod on Wednesday, August 18, 2021 6:46 PM

7j43k
Comes in an assortment of radii and lengths.

Ed, those are worthless for the short curves and their transitions that are being described here.  Does the company make a special short 'transition' gauge for these ladders?  They should...
I'm well aware of the theory; I just saw it taught again.  I'm also aware of the theory of the coaxial escapement.  In order to actually build either, it is helpful to have methods and dimensions, not advice to kinda-sorta curve stuff to fit and live with any glitches.

I suspect cuyama could produce a template comparable to the transition spiral in MR that could be printed off, cut in thin sheet or whatever, and used to set this track by track.

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Posted by 7j43k on Wednesday, August 18, 2021 6:29 PM

Overmod

is there a source for making up a template or gauge to form this curve in flextrack connected to each 'shortened' switch, which might make this simple ? 

 

 

 

Comes in an assortment of radii and lengths.

 

Ed

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Posted by richhotrain on Wednesday, August 18, 2021 5:49 PM

riogrande5761

One of the things I like about Peco turnouts is they are already very short, the likihood of needing to trim them is much lower.  But I've trimmed Atlas and other turnouts as needed to get them to fit. 

That is a distinct advantage of Peco over Atlas for a turnout - - 3". Peco is 9" in length whereas Atlas is 12" in length for a Code 83 #6 turnout. That can be crucial when space is at a premium.

Rich

Alton Junction

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Posted by cuyama on Wednesday, August 18, 2021 5:39 PM

Overmod
I seem to have missed this, but what's then length, nominal radius, and 'source' of the little pieces of curve inserted to make the trick work? is there a source for making up a template or gauge to form this curve in flextrack connected to each 'shortened' switch, which might make this simple ? 

In the past I have just made it with flextrack in N scale, it would also work for other scales. I use the minimum radius I have chosen for the yard (which might be different from the rest of layout). How much curve depends on the length and frog number of the turnouts that you choose as well as track spacing of the yard tracks – to me it’s a little bit of trial-and-error.

About 2-3 degrees of curvature added to the diverging leg of the first turnout has often worked well for me in designs for others – and then the corresponding curve on each yard track.

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Posted by Overmod on Wednesday, August 18, 2021 5:32 PM

I seem to have missed this, but what's then length, nominal radius, and 'source' of the little pieces of curve inserted to make the trick work?

is there a source for making up a template or gauge to form this curve in flextrack connected to each 'shortened' switch, which might make this simple ? 

 

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Posted by riogrande5761 on Wednesday, August 18, 2021 5:22 PM

One of the things I like about Peco turnouts is they are already very short, the likihood of needing to trim them is much lower.  But I've trimmed Atlas and other turnouts as needed to get them to fit.

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by 7j43k on Wednesday, August 18, 2021 4:49 PM

cuyama

I made the graphic a long time ago, so I don't remember why. But you're right, apples-to-apples would have been better – and one would probably need to trim the Walthers to use them with curves as shown with 2" spacing. 

 

It's a terrific graphic, and I'm glad you posted it.  It does give a very good sense of how it works.

I did a bit of calculating, and came up with shortening the Walthers switch by about 2.1" to keep the 2" spacing.  There's about 3.6" available for removal in the Walthers turnout, so should be no problem.

 

Ed

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Posted by cuyama on Wednesday, August 18, 2021 3:22 PM

7j43k
Why the change from the Walthers #6 to the "NMRA" #6? My guess would be that the "NMRA" are shorter, so as to maintain the 2" spacing.

I made the graphic a long time ago, so I don't remember why. But you're right, apples-to-apples would have been better – and one would probably need to trim the Walthers to use them with curves as shown with 2" spacing. But since folks (OK, one folk) expressed confusion about how it worked, I just posted what I had on-line already.

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Posted by Doughless on Wednesday, August 18, 2021 3:19 PM

Lastspikemike
It's how you also shorten the whole ladder without also narrowing the track centres closer together.

If you look at real railroads, in tight spaces they try to put the points of the next turnout as close to the closure rail of the previous turnout as possible.

Our model track components can't do that, they need lots of track in between to maintain structure, but ME tries to as much as is feasible by making some of the components as stumpy as possible.

If you could stack the points one after the other, you could have broader radius closure rails (and the same radius beyond the frog) and an upright ladder that doesn't take up a lot of linear inches.  Those are the real goals here, broad radius with little length.

As long as the closure rail radius is broad enough (as well as the embedded radius of the whole shmear including point rails), what the resulting frog number happens to be is tertiary.

- Douglas

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Posted by 7j43k on Wednesday, August 18, 2021 2:39 PM

cuyama

 

 

Why the change from the Walthers #6 to the "NMRA" #6?

My guess would be that the "NMRA" are shorter, so as to maintain the 2" spacing.

It looks like, very roughly, one picks up 11" more yard capacity with the lower design--a nominal two cars.

 

Ed

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Posted by cuyama on Wednesday, August 18, 2021 12:19 PM

--
One puzzle is how the yard ladder system can yield more siding length in the same space while using the 2"+ track centres.

As others have said, this is a well-established idea. Adding a slight curve to the diverging leg of the first turnout increases the angle a bit, increasing (slightly) the length of the body tracks. One can do this with any turnouts, the ME system just includes the curves as part of the pre-fab turnouts. In the example below, the added curves are in red.

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Posted by 7j43k on Wednesday, August 18, 2021 11:49 AM

By rotating the spine of the stack of switches more to the vertical (compared to the incoming yard lead), the tracks at the "top" of the yard can be a bit longer.  There has to be a slight curve to bring the diverging tracks back to parallel with the yard lead.

The spacing of the switches in the stack has to lessen, too (along the length of the stack); so that you can maintain your track spacing (which otherwise spreads out a bit).

This clever trick ends when you have shoved the stack of switches together enough so that the points of one are just after the frog of another.

 

ME does it with special switches.  It would work with regular ones, too.  Maybe not as well/smoothly, though.

 

Here's an example using Atlas Customline #6's:

 

For the straight part of the switch, there are 4 ties beyond the points, and 12 ties beyond the frog.  Let's remove all but two at each location.  The switch is now 71% as long as a stock switch.

Recall that it's been said that the stock switch gives you 2" yard track spacing.  If that's the case, a ladder built of the modified switches would give you a spacing of 1.42".  

Assuming you want to stick with the 2" spacing, you could regain that by putting a bit of curved track in, after the frog, on the diverging track.  Yes, I can prove it.

This brings the yard tracks "down" at an angle.  If you rotate the spine of switches (and the associated yard tracks) into a more "vertical" position, the yard tracks can again be parallel to the yard lead.

And in doing this, you get progressively longer yard tracks as you go "up".

 

 

Ed

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Posted by Doughless on Wednesday, August 18, 2021 9:28 AM

Lastspikemike
One puzzle is how the yard ladder system can yield more siding length in the same space while using the 2"+ track centres. That seems impossible geometrically.

I have not seen the system so I am speaking from what I read about it.  I think the goal is to make the ladder track more upright rather than stretched out to save length, which one of the main problems with yards and model railroads.  I think they stack them together to keep the geometry of the closure and diverging tracks as gentle as possible while still saving length. 

And just a guess:  The result is a ladder that has as much linear length as a ladder built with a traditional #4 frogged ladder, but able to use a #5.

I'll let you figure out if that's the case and how effective that is.

- Douglas

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Posted by maxman on Wednesday, August 18, 2021 9:08 AM

ATLANTIC CENTRAL

 

 
maxman

An innocent comment based on an observation and more froth gets spewed.

gg.  you guys need to get a life.

 

 

 

It is interesting how "facts" are so bothersome to some people.........

Just another reason I spend way less time here.

Sheldon

 

Facts?  Facts?  What "facts"?  I said nothing that required a "fact" check.  I only passed along someone else's statement.  Sorry that you find that bothersome.

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Posted by Overmod on Wednesday, August 18, 2021 6:28 AM

Colorado Ray
if you want more information than you'll ever need on yard design, check out the FRA Yard Design Manual. https://rosap.ntl.bts.gov/view/dot/32572/dot_32572_DS1.pdf?

 Be sure to read and comprehend Chapter 2 first.  

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Posted by ATLANTIC CENTRAL on Wednesday, August 18, 2021 5:56 AM

maxman

An innocent comment based on an observation and more froth gets spewed.

gg.  you guys need to get a life.

 

It is interesting how "facts" are so bothersome to some people.........

Just another reason I spend way less time here.

Sheldon

    

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Posted by Colorado Ray on Tuesday, August 17, 2021 9:35 PM

One thing to consider is different spacing for the receiving and departure yards from the classification tracks.  Modern practice would use 20 ft spacing for the R/D tracks to provide a safe environment for car inspectors.

if you want more information than you'll ever need on yard design, check out the FRA Yard Design Manual.

https://rosap.ntl.bts.gov/view/dot/32572/dot_32572_DS1.pdf?

Ray

 

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Posted by maxman on Tuesday, August 17, 2021 9:34 PM

An innocent comment based on an observation and more froth gets spewed.

gg.  you guys need to get a life.

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Posted by ATLANTIC CENTRAL on Tuesday, August 17, 2021 5:07 PM

maxman

I don't know if this was mentioned above or not.  However, I was looking at the literature for the MicroEngineering Ladder Track System and they say that their system results in a "minimum track spacing of 2-1/16 inch (the NMRA standard) between body tracks".

 

Well, I'm not trying to make this thread any more crazy than it already is, but I did mention the NMRA Recommended Practice for tangent track a while back, and it is not 2-1/16".

First, the NMRA no longer has track centers as a "Standard" but rather as a "Recommended Practice". A trip to their web site will help explain that difference.

RP 7.1 says that the recommended track centers for tangent track can/should be based on prototype dimensions based on era.

MODELING ERA                PERIOD            CENTERS

Old-Time/Narrow Gauge    Before 1920      12 feet

Classic                               1920 to 1969     13 feet

Early Modern                     1969 to 1983     14 feet

Modern                               After 1983         14 feet

 

If we just go with the 14 foot number, that translates to 1.931", or, a bit under 1-15/16".

2" track centers are 14'-6"

2-1/16" track centers are just under 15'

The ME yard ladder is an interesting product, but not one I'm interested in. It uses #5 turnouts, it stacks them in very tight and adds a curve after the frog. This is common on ther prototype, but they are using larger turnouts.....

I have built yards with Atlas #4 Custom Line turnouts (which are really #4.5), but will never do that again, at least not on a steam era layout.

So I have little confidence that a yard built with #5's, and with a sharper ladder angle, would be satisfactory for my needs. 

Still happy to be using Atlas Custom Line designed completely around 2" track centers, making 2" track center yard ladders, and 2" crossovers with no cutting or filling, and who's #6 is the most gentle curve #6 on the market.

Sheldon

    

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Posted by Doughless on Tuesday, August 17, 2021 3:58 PM

maxman

I don't know if this was mentioned above or not.  However, I was looking at the literature for the MicroEngineering Ladder Track System and they say that their system results in a "minimum track spacing of 2-1/16 inch (the NMRA standard) between body tracks".

 

Well, they've got the word ENGINEERING right in their name, so they have to pretend that the 1/16th inch matters. Big Smile

- Douglas

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Posted by maxman on Tuesday, August 17, 2021 3:16 PM

I don't know if this was mentioned above or not.  However, I was looking at the literature for the MicroEngineering Ladder Track System and they say that their system results in a "minimum track spacing of 2-1/16 inch (the NMRA standard) between body tracks".

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Posted by 7j43k on Monday, August 16, 2021 3:45 PM

mikeGTW

 

 
7j43k
Lastspikemike Straight yard tracks can be down to 1.5" easily.  7j43k Hey, Mike. Still waiting for your working example of 1.5" track spacing.   Ed

 

 

Ed I have four different wide vision caboose's  so that 1.5" or even the 1 3/4" is not good for me  

Mike 1 1/2 will probably tell you to pull your cabooses off in your arrival/departure tracks, and you won't have any trouble in the yard itself.

Besides I use #6 atlas swiiches and they are 2"  on center for ladder tracks

Rail nippers and files can shrink that distance right down.  Should you care to.

Sometimes I wonder does someone even have anything to photograph maybe that's why no posting of pictures

It's a LOT of work, unless you're set up to do it regularly.  In my opinion.  Still, I'm inching (millimetering?) towards it.  I've got a nice Flikr account somewhere that I paid real money for.  Someday......

Or.  I could just play with my trains, instead.  And yack with my n'er-do-well pals online.

 

Ed

 

 

 

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Posted by mikeGTW on Monday, August 16, 2021 3:12 PM

7j43k
Lastspikemike Straight yard tracks can be down to 1.5" easily.  7j43k Hey, Mike. Still waiting for your working example of 1.5" track spacing.   Ed

 

Ed I have four different wide vision caboose's  so that 1.5" or even the 1 3/4" is not good for me  

Besides I use #6 atlas swiiches and they are 2"  on center for ladder tracks

Sometimes I wonder does someone even have anything to photograph maybe that's why no posting of pictures

 

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Posted by 7j43k on Monday, August 16, 2021 2:16 PM

Lastspikemike

Straight yard tracks can be down to 1.5" easily. 

7j43k

Hey, Mike.

Still waiting for your working example of 1.5" track spacing.

 

Ed

 

We had to take it apart to move the layout. Sorry, a never to be repeated situation.

 

 

Ed

 

 

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