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Turnout size

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Turnout size
Posted by Orangeman on Monday, October 14, 2019 6:13 PM

I'm a month or more away from actually building a layout, but was wondering what size turnout I should use in HO scale for modern era. Seems #8 is the best, but wondering if #6 would work well too or would it cause problems? 

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Posted by hon30critter on Monday, October 14, 2019 7:46 PM

Hi Orangeman,

Our club has close to 80 Atlas Code 83 Customline #6 turnouts installed and they work fine, but if you have the space why not use #8s?

Edit: I will offer one caveat about The Atlas Code 83 #8 turnouts. The #8s have cast point rails whereas the #6s and #4s have stamped point rails. In my limited experience with the #8s, I found the cast points to be very fragile. I made an attempt to slightly adjust the tab on the point rail where it attaches to the throw bar because the point rail wasn't matching up with the stock rail as well as it could. I applied very little force but the tab broke off. The cast point rails will not take solder so the turnout was toast.

Lots of people have used the Atlas #8s with great success. Just don't go mucking around with them and you should be fine.

Dave

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Posted by selector on Monday, October 14, 2019 10:18 PM

It might help to understand why a #12 would be a "better" turnout to use over a #10, or even a #5.  The truth is, in our confined spaces, most rolling stock will do very nicely on a #5...if that's all that will fit into the track plan.

The larger numbers mean longer turnouts, and those long turnouts, while looking nice 'n prototypical, take up a lot of room.  So, since most of us find that it takes some serious planning to get many track arrangements into a confined space, we opt to have the lower frog numbers if they'll work, and if they'll offer us more options for other track arrangements.

Really, it all begins with the concept, and those begin with a firm understanding of what we want out of our model trains in terms of operating.  We go from a simple oval that doesn't need a single turnout, thanks very much, to complicated yards on large layouts where several types of turnouts can often be found.  For example, the single and double slip turnouts are used in N. America, but not nearly as often as they are used in Europe, particularly in the Balkans and former Soviet Bloc countries. In Slovenia, Slovakia, The Czech Republic, and similar, they're litterally everywhere, and in numbers.

I would ask you, in return for your question, what is a #8 going to offer you that a much more common #6 does not?  If you have an informed response, you already have placed your own answer before you...kinda....no?

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Posted by RR_Mel on Tuesday, October 15, 2019 12:54 AM

I’ve had four layouts in my model railroading career and never used a turnout larger than a #6.  My current layout has #6 turnouts on the mainline and #4s in the yard, all Atlas code 83 with the exception of three Peco code 100 in my hidden areas.
 
My layout is small and using 85’ passenger cars looked out of place but they all went through all my turnouts with out any problems.  I cut back to 72' as my longest car. 
 
I’ve never used #8s but I have seen post on the MR Forum about the longer #8 and larger having electrical power pickup problems with short wheelbase locomotives with the longer frog turnouts.
 
I made provisions for powering all of my frogs because I have several 0-4-0, 0-6-0 and 4-4-0 locomotives.  I have not needed to power my #6 frogs as even the 0-4-0 doesn’t have any problems in my turnouts.
 
 
Mel
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
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Posted by SeeYou190 on Tuesday, October 15, 2019 6:00 AM

Basically, any commercially made, mass-produced model will pass through a #6 turnout with no problem. Everything I own must be able to pass through a crossover made of Kato Unitrack #6 crossovers.

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Some large brass models require #8 turnouts.

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Probably 90% of equipment will pass through a #5 and 80% through a #4.

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I use turnouts with all frog sizes. #4s are in switching areas where the big steamers and E units do not go.

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#8s on the outer mainline are required, but there are only two planned turnouts on the outer main. The inner mainline uses #6 turnouts into the yard.

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-Kevin

.

Wink Happily modeling my STRATTON & GILLETTE RAILROAD. A Class A line located in a personal fantasy world of semi-plausible nonsense on Tuesday, August 3rd, 1954.

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Posted by riogrande5761 on Tuesday, October 15, 2019 8:45 AM

I would recommend as a good compromise between performance and space to use #6 minimum turnouts in the main yard and #8 for passing sidings and/or crossovers.  In tight industrial areas, a #5 would be a good minimum.

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by rrinker on Tuesday, October 15, 2019 2:34 PM

riogrande5761

I would recommend as a good compromise between performance and space to use #6 minimum turnouts in the main yard and #8 for passing sidings and/or crossovers.  In tight industrial areas, a #5 would be a good minimum.

 

 That's pretty much my plan. Use an appropriate size in each position, not one size fits all.

                            --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by NHTX on Tuesday, October 15, 2019 3:52 PM

     Prototype railroads used to roster a lot of four axle switchers due to curves in industrial areas that were laid when some car movements were made with horses or mules and we know what their minimum radii are.  When cars grew beyond 20-30 ton capacity and over 30 feet in length, teakettle switchers supplanted the livestock.  Up until recently, there were railroads that prohibited six axle power from entering any industrial track on the railroad.  What carload freight industrial track left is patrolled by 20+ year old four axles or, has been rebuilt to accommodate demoted SD40-2s.  In otherwords #8s at passing sidings and mainline crossovers, #6s in the yards and industrial areas--if you're not tight on space.  I've never used #5s, but if it were necessary, that would be forbidden trackage for the six axles, even the SD-9s. 

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Posted by Jwmutter on Tuesday, October 15, 2019 4:49 PM

Since you’re modeling modern era, you likely will be running longer cars and bigger motive power.  If that’s the case, the longer turnouts will perform better, but may restrict your track planning options, depending on the space you have available.  

I am modeling 1975, with lots of 89’pig flats and auto racks, plus 86-foot auto parts  cars, and I used #6s in my yards and #8s on the mainline — mostly for appearance.      Most of the longer cars will run on the shorter turnouts but don’t look very good doing it.  “S” curves introduced by successive #6s (like in a crossover) can be an operational headache, too.

My opinion is that you should use the largest turnouts you can fit in your space.

Jeff Mutter

Erie Lackawanna’s Scranton Division, 1975

http://elscrantondivision.railfan.net

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Posted by peahrens on Wednesday, October 16, 2019 9:57 AM

The two key issues are prototypical looks and equipment minimum radius.  We tend to fudge on the former significantly and still think it looks fine.

On equipment min radius requirements, most HO items are ok with 22".  Ensure you have or plan no exceptions to that, or accept some operating restrictions for a special item.  One example is the very long (4 axle trucks) Athearn UP diesel DDA40AX which has a rather large 28" radius recommended.  Maybe some many drivers brass steamers as well?

Regarding min radius, I believe even the #5 turnout has a much larger than 22" closure rail curve.  You can see the specs at the NMRA standards / recommended practices pages (RP-12).  EDIT:  RP 12.11 (HO) shows the closure curved track radius as (rounded) 24.2", 36.8" and 63.0" for turnouts #5, #6 and #8, respectively.

In my case on a smallish 5x9 layout, I used #6 on mainline takeoffs, #8 on one smoother mainline split and #5 in yards.  All good for 6-axle diesels and 4 driver axle steamers.  

I do not have any straight crossovers (do have two with curved turnouts) but there you have a bit of an "S" curve so consider that as a special case perhaps.  As an example, I would much prefer #6's over 5's in that case.

Also, in yards note that if you extend a diverging track to parallel the straight through route you are creating an "S" curve.  But if you curve the straight through route to parallel the diverging route there is no "S" curve.  So how you arrange your turnouts' track extensions is something to consider.

Paul

Modeling HO with a transition era UP bent

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Posted by Doughless on Wednesday, October 16, 2019 10:21 AM

I agree with JWMutter.  If you're doing modern era, go with #8's, as long as they work well.  Switcher locos might have difficulties traversing the long frogs.  But GP-type locos should be fine.

As others have mentioned, #6s look fine and work better for smaller locomotives.

- Douglas

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Posted by doctorwayne on Wednesday, October 16, 2019 11:53 AM

While I have some larger turnouts on my layout, they're there only because they were free (from a friend who didn't need them) and I had ample room for them.

My layout is almost entirely steam-powered, and even Consolidations, Mikados, and Mountains can negotiate #6 turnouts easily, with rigid wheel bases longer than those on most 6-axle diesels.  They also have no trouble with #2.5 wyes or #5 turnouts.
While #8s (and #10s and #12s and whatever other long turnouts you wish to scratchbuild) do look more prototypical, they eat-up a lot more space, too.  This comes at the expense of industrial siding-lengths, and the length of passing sidings, and in the wrong location, will also impinge on your curve radii, depending on their location relative to the curves.

Wayne

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Posted by BATMAN on Wednesday, October 16, 2019 11:59 AM

Don't forget to look at curved turnouts. They opened up much better possibilities for me on my little layout, I think I have seven curved turnouts all together.

Brent

It's not the age honey, it's the mileage.

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Posted by York1 on Wednesday, October 16, 2019 12:00 PM

I just started model railroading last year.  I am building in N Scale.

Not knowing all the ins and outs, I went with shorter turnouts on the entire layout.  Later, after I added a section, I am now running passenger cars through short turnouts.

I have never had an issue with them working, or with derailments.

But they do not look good with the cars making sharp turns.

If I were to start over, I would use the longest turnouts I could fit.

Saints Fan John

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Posted by ATLANTIC CENTRAL on Wednesday, October 16, 2019 12:31 PM

Taking into account our already selectively compressed curves, #8 turnouts seen to be more than large enough to convey that sense of gracefulness on a high speed class one line.

After that, #6 turnouts are large enough for nearly all equipment. 

The Atlas custom line #4 is really a #4.5, so it is pretty comfortable for all smaller equipment, industrial trackage etc.

I have found that my Spectrum USRA Heavy Mountians do not really like the #4.5, and don't like some other manufacturers #5, but are more than comfortable thru any #6, even at a pretty good speed.

So I use all #8 and #6 turnouts except for true "industrial" area trackage, where I do use the Atlas #4.5

Even with a mainline of #6 and #8 turnouts, and minimum curves of 36" radius, I restrict my locomotive purchases to locos of about a scale 21' rigid wheel base. My largest rigid wheel base loco are several USRA light 2-10-2's, and they are the only five coupled locos I have. 

Sheldon

    

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Posted by ATLANTIC CENTRAL on Wednesday, October 16, 2019 12:47 PM

Additionally, I do use curved turnouts to great advantage in saving space and allowing the use of larger turnouts.

I have developed methods for actually bending Atlas #6 and #8 turnouts into very gentle large radius curved turnouts. Additionally I simply hand lay other curved turnouts I made need, as none of the commercial  ones are up in the large radius range of my curves.

Sheldon

    

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Posted by mobilman44 on Wednesday, October 16, 2019 1:37 PM

I used Atlas 8s for the mains, 6s for submains, and 4s for most sidings (others 6s).

The 8s do take up more room, but look so much better in operation - especially with long cars.

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, modeling the "postwar" Santa Fe and Illinois Central 

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Posted by jjdamnit on Wednesday, October 16, 2019 2:41 PM

Hello All,

Turnout size is more a product of space over preference, as is curve radius.

You did not mention the size and configuration of your pike. Around the walls, island, walk-in?

What type of motive power are you running? Six-axle diesels, 4-8-4 steamers or larger?

I would love to use #6 or #8 turnouts, but on a 4'x8' pike it is not practical.

The turnouts I use are Atlas Snap Switches and PECO #2s.

I have managed to incorporate a single Atlas Mark IV #6 and a PECO curved turnout but I had to modify the curved turnout to fit the space.

Because of the limitations of the turnouts and curves the bulk of my motive power is 4-axle diesels and 0-6-0 steamers. 

For the mainline coal drag I run a four-unit GP40 MU. The coal loading siding uses #2 PECO turnouts so there is a speed limit as this consist passed through the tight turnouts.

For switching purposes I do have a cow and calf SW 1200 MU along with a consist of two GP30s with a GP30-B unit.

Yes, larger numbered frogs are always preferred but if you don't have the space #6 will do the trick.

Hope this helps.

 

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by Orangeman on Wednesday, October 16, 2019 10:06 PM
Thanks for all the info. I would like to have a double main so I will use #8s for the crossovers. I think #6s for the sidings. I'll admit I have no idea what I'm doing, but everyone has given some great input. Thanks.
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Posted by riogrande5761 on Thursday, October 17, 2019 7:20 AM

Orangeman
I think #6s for the sidings.  

You could use #6 turnouts for sidings but if you run long equipment, such as 89' autoracks and/or flat cars, or passenger cars, then #8 would be MUCH better and not take up that much more space.

Keep in mind that there can be S curves where the turnouts go into a siding.  I am going with #8 turnouts at those locations to minimize the negative effects of the S curves.

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by Orangeman on Saturday, October 19, 2019 10:09 PM
Thanks Rio, I will keep that in mind. I just picked up some #6s on Ebay, but will still consider the #8s as I do have some auto racks and 89' flats.
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Posted by SeeYou190 on Saturday, October 19, 2019 11:43 PM

You will probably be happy with the #6s.

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You might like #8s better for crossovers with the long cars.

.

-Kevin

.

Wink Happily modeling my STRATTON & GILLETTE RAILROAD. A Class A line located in a personal fantasy world of semi-plausible nonsense on Tuesday, August 3rd, 1954.

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Posted by riogrande5761 on Sunday, October 20, 2019 2:00 PM

Sidings can be geometrically like crossovers which is why it may be better for longer cars.  Of course #6 turnouts in yards will have A curves but operations are much slower in yards.

Rio Grande.  The Action Road  - Focus 1977-1983

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