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#1, 2, 3, 4, large, medium, small? WHICH SWITCH?

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#1, 2, 3, 4, large, medium, small? WHICH SWITCH?
Posted by Anonymous on Saturday, March 3, 2007 1:08 AM
I think I have decided to go N guage and use Atlas switches and track. But which switch. What do the #1 etc mean. Do I try and match diameter of track to diameter of switch? Peco seems to have large medium and small? What is all this? Somewhere that explains it?
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Posted by Jacktal on Saturday, March 3, 2007 8:01 AM

To me,choosing Peco turnouts is a no contest.They are the best design I know of with their track position holding spring meaning that they can be thrown by twincoil motors.If you choose to power them with slow motion types machines (Tortoise),you then remove the spring and that's all there is to it.Peco also offers a wider selection of turnouts like slips,double crossovers,curved TO's,etc.Their small TO's are 12 in. radius,medium are 18 in. and their large are 36 in. while their curved TO's combine 36 and 18 in. radiuses.And if you go with code 80,Peco TO's can be used with Atlas without any modification.

Their drawback,minor to my mind,is that tie spacing is based on British prototype so many don't like them for that reason.If you want the american prototype look,there are a few other brands,some pricey though,that offer these .But since I haven't had any experience with them,I can't tell you more.

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Posted by Anonymous on Saturday, March 3, 2007 8:19 AM

The reason I am going Atlas is I do not want to install the undertable motors. So it is above table motor. Sorry, I dont want to crawl around under there.

But, what I need to know, is what do the 1, 2..8, or small medium large mean?

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Posted by NevinW on Saturday, March 3, 2007 8:48 AM

The numbers refer to the angle that the curved side of the turnout diverges from the straight side.  In HO, a #4 means the diverges 1 inch (unit length) in 4 inches (unit length).  A #6: 1 inch in 6 inches, an #8: 1 inch in 8 inches.  I have attempted to illustrate it below.  Maybe someone can paste a drawing that better shows the concept.  A #4 is a sharper angle than a 6 or 8 and will not handle longer engines or cars as well.  Real railroads use 12, 18, 24 angle switches.  

|                     |

|                     | 

|                     |

|_                   | 

#4                   |

                      |_

                      #6

each | = 1 inch 

 

Hope this helps.   -Nevin  

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Posted by ericboone on Saturday, March 3, 2007 8:58 AM
 pilot wrote:

The reason I am going Atlas is I do not want to install the undertable motors. So it is above table motor. Sorry, I dont want to crawl around under there.

But, what I need to know, is what do the 1, 2..8, or small medium large mean?

Small, medium , and large simply refer the the radius of the diverging track as previously stated.  I think that is typically only used with European manufacturers such as Peco.

Most other manufacturers use the frog number.  It is a way to define the angle of the frog and diverging track.  With a #4 turnout, if you travel 4 units of measure down the straight or normal route, the diverging route will be 1 unit of measure over from the straight track.  Basically, the higher the number, the longer the turnout and the less sharp the diverging angle and radius is.  Most model railroaders try to use a #6 as their minimum, although you could use a #4 if you absolutely needed.

Note that with wye turnouts, because both routes diverge, a #2 wye will have the same size diverging route radius as a standard #4 turnout.

Frog Angle = arctan ( 1 / Frog Number )

Arctan is also labelled as tan-1 on many calculators.

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Posted by tomikawaTT on Saturday, March 3, 2007 8:58 AM

The question is not quality or brand loyalty, the question is turnout geometry.  (Strictly speaking, the 'switch' identifies the moveable points and whatever holds them together and in position.)  In North American practice, the number specifies the distance (in specified units - inches, scale feet, centimeters or whatever) traveled along the running rail from the frog point to achieve a one specified unit separation between the flange sides of the diverging railheads.

 The larger the number:

  • The longer the turnout.
  • The longer the radius of the curved closure rail between points and frog.
  • The more space it takes to put together a specified track arrangement.
  • The easier it is to run long-wheelbase locomotives, passenger cars and 89 foot humonguboxcars.

Peco is different in that the rails through the frog are curved.  Their terms; small, medium and large, refer to the curve radius (which I do not know off-hand.)

As for which is the best commercial turnout, I don't even want to open that can of slithery, slimy critters!  (I, personally, build all of my specialwork from raw rail, track gauge in one hand and soldering gun in the other.)

Chuck (modeling Central Japan in September, 1964)

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Posted by Anonymous on Saturday, March 3, 2007 9:29 AM
OK, thanks. So if I the smallest Nscale radius is 12" and the largest I have is 22", and I have plenty of room, which number Atlas switches should I use? #5 or #6 or ???
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Posted by SpaceMouse on Saturday, March 3, 2007 11:25 AM

 pilot wrote:
OK, thanks. So if I the smallest Nscale radius is 12" and the largest I have is 22", and I have plenty of room, which number Atlas switches should I use? #5 or #6 or ???

IT depends on what you run. I run small steam and my engines are smaller than my S1 switcher so I can get away with #4 turnouts. If you are running Geeps or other 4 wheel trucked engines, think #5 or #6. For 6 wheel trucked engines think #8 or more. Also, consider the rolling stock. The longer the rolling stock, the higher number turnout.

What era are you modeling? What types of engines are you planning on using?

Chip

Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.

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Posted by selector on Saturday, March 3, 2007 11:43 AM

Pilot, generally, the #6 turnout is a good all-round choice for an entire layout if you want to keep things simple.  A #6 diverging route substitution or real radius relates to medium to broad curves, while the #8 turnout and higher numbers fall into the broad range of curves entirely.

As Space Mouse has said, you can get away with #6 turnouts if they are what you can get cheaply and easily...they will suffice.  However, if you want to keep your larger curves on your high-speed areas moving smoothly, #8 turnouts are a better idea; keep the #6 turnouts to slower track and to your yard.  Turnouts sharper than #6, such as the #4-5 range, are really quite abrupt and limited to smaller stock and engines that might be used in confined spaces such as an alley between buildings where there is a team track or some other industrial siding.

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Posted by Anonymous on Saturday, March 3, 2007 12:50 PM

Right now my Nscale layout design has three loops. An outside, highspeed loop 22" radius with minimal turnouts. An 20" innerloop with more turnouts and sidings. And an inner figure 8 with 12" radius and steep grades. I plan to run ALL N guage equipment I can, realizing I will be limited on the inner figure 8. I am modeling 1950's Denver on the outer runs (both steam and diesel) and a tourist train and old time stuff on the figure 8 (which goes up to the mountains).

Perhaps #8's on the outer and intermediate loop and #5's or #4's? on the inner figure 8???

Are the meaning of the numbers the same for HO?

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Posted by galaxy on Saturday, March 3, 2007 3:53 PM

With which witch's sandwich will we switch which witch's switch to Ipswhich?

 

Does that cover it, or have I got the wrong thread?

Speaking of threads....The wellbred read the dreaded red thread with dread.

Ok, so I'm not Dr. Suess (or am I?)..hope I made you laugh!

I'll bet you can't say the first on 5 times fast!

-G .

Just my thoughts, ideas, opinions and experiences. Others may vary.

 HO and N Scale.

After long and careful thought, they have convinced me. I have come to the conclusion that they are right. The aliens did it.

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Posted by ericboone on Saturday, March 3, 2007 5:01 PM
 pilot wrote:

Are the meaning of the numbers the same for HO?

 

Yes.

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