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Understanding switches?

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Understanding switches?
Posted by krakow on Thursday, November 26, 2020 12:46 AM

I am planning my first real layout, the benchs framework is mostly complete. As of now I am going with Peco code 100 flex track, cork roadbed. 

My main line is a 26 radius and the inside line is 24. 

 

The biggest road block I have run into is simply trying to understand switches. I have gotten the Model railroader basic trackwork guidebook and it has been helpful but doesnt lead to all of my questions being answered. 

 

The yard is a planned expansion so the benchwork hasnt been started for that yet. 

 

I originally did the plans for PECO switches, but am considering Atlas. All the switches will be hooked up to the MTH AIU and I don't plan on making anything insulated. (I am going to be running all MTH DCS)

How havent been able to find what radius the PECO switches actually are, and what are the equvalents in Atlas or others? Are the switch radius the same as normal curves?

Layout plan

Tags: Atlas , beginner , Peco , Switches , Track
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Posted by gregc on Thursday, November 26, 2020 3:45 AM

a "standard" turnout has straight diverging rails and is not designed to replace a curved section of track at the beginning of a curve

however some turnouts are designed to replace a curved section of track.    since a turnout has a short straight section near the points, it can only replace the curved section where it starts

atlas "snap-switches" can fit in 18" and 22" curves.   peco switches may fit curves with metric dimensions.

greg - Philadelphia & Reading / Reading

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Posted by richhotrain on Thursday, November 26, 2020 5:43 AM

In looking at your track plan, there is a single crossover from the inner track to the outer track to reach the yard, but there is no provision to crossover back to the inner track. You ought to consider another single crossover from the outer track to the inner track, perhaps just down the mainline from the existing single crossover or somewhere on the right side of the layout.  

Rich

Alton Junction

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Posted by RR_Mel on Thursday, November 26, 2020 8:02 AM

Good catch Rich, it would be a bummer to have to backup that far to get to the mainline.  Also there is no way to reverse directions, one way layout counter clockwise.
 

Mel



 
My Model Railroad   
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Bakersfield, California
 
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Posted by SeeYou190 on Thursday, November 26, 2020 9:45 AM

krakow
All the switches will be hooked up to the MTH AIU and I don't plan on making anything insulated.

I have a question, why are you using the Accessory Interface Unit to control the turnouts (switches)?

This device adds another layer of difficulty in wiring, and makes control of individual turnouts a bit more fiddly.

What advantage is it offering over just attaching the turnout motors to toggle switches (or push buttons) on the control panel?

-Kevin

Living the dream.

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Posted by krakow on Thursday, November 26, 2020 10:17 AM

Going with something like this Atlas switch, where can I find out what the radius actually is? Since it being a straight turnout are there still  labeled with radius like curved switches are? What do #4 or #8 translate to?

https://www.trainworld.com/manufacturers/atlas/atlas-ho-scale/code-100-track-accessories/atlas-282-code-100-4-mark-iv-turnout-right/

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Posted by rrinker on Thursday, November 26, 2020 10:36 AM

 A numbered turnout has a stright frog that diverges at a set angle. That At;as #4 is actually a #4 1/2. That menas for every 4 1/2 units (inches, feet, miles, sheets of paper - it doesn;t matter), the diverging side will diverge 1 unit. A number 6, that takes 8 units of length to diverge 1 unit. There are measurements such as closure rail radius and substitution radius but subsitution radius is a bad term - it does not mean you can swap in the diverging side of the turnout for a curve of that radius, it doesn't just drop in like that.

 Peco Code 83 track uses bumbered turnouts. Peco Code 100 uses the "small, medium and large" names. Atlas Snap Track has a radius, 18" or 22", but it's still not an exact drop in replacement for a piece of curved track of that radius.

 Why MTH DCS for an HO scale layout? Especially sionce MTH has announced they are closing up shop. Their locos will run on DCC, but the DCS system won't run DCC locos without ALSO buying a DCC system. You're limiting yourself to a small subset of the possible loco types and road names out there with DCS.

 And as Sheldon mentioned - even most die hard DCC users don't bother controlling turnouts through the system, they are ALL equally awkward at switching between train control and accessory control and then back. If you're going to be following your trains around anyway, having buttons or toggles right on the fascia in front of the turnout it controls is a lot cheaper and more intuitive. And if you're doing this to allow fully automated operation - that brings me back to questioning the choice of DCS, because there are limited options. There are at least two major applications for setting up fully automated operation with DCC - JMRI and RR&CO. JMRI is even free.

                                  --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 gregc on Thursday, November 26, 2020 10:41 AM

krakow
What do #4 or #8 translate to?

see Turnouts .. what you need to know

greg - Philadelphia & Reading / Reading

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Posted by RR_Mel on Thursday, November 26, 2020 10:57 AM

krakow

Going with something like this Atlas switch, where can I find out what the radius actually is? Since it being a straight turnout are there still  labeled with radius like curved switches are? What do #4 or #8 translate to?

https://www.trainworld.com/manufacturers/atlas/atlas-ho-scale/code-100-track-accessories/atlas-282-code-100-4-mark-iv-turnout-right/

 

I inserted the picture of the #4 MarkII turnout in my CAD and it measures 22” radius.

 


Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

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Posted by krakow on Thursday, November 26, 2020 3:48 PM

Mostly because I already had the system with G scale, while I may branch out to other companies later. I had all MTH HO engines before I even started this layout. I had a Broadway Dreyfuss Hudson which didnt leave a great impression on me for DCC, it had trouble even making it around the circle where as MTH ran perfectly. While this may not be a good enough reason as to why, its what happened to me. I can always get a different DCC system later and still run all the MTH engines with them.

 

Having "DCC" switches was not really something I had any concerns with. Being able to change all the switches from my iPad with the MTH app or any of the other alternatives that work on computers or iOS appealed to me.

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Posted by MisterBeasley on Thursday, November 26, 2020 4:06 PM

I had a section of my layout in Code 100 made with Atlas track and Snap-switches, but I had a few places where I used Peco turnouts.  As I recall, they were very close to drop-ins.

Think about how you will drive the turnouts.  Atlas points flip over easily, but require constant pressure to keep them up against the stock rails.  A Peco turnout has a spring which holds the points in place, but they are harder to push over and need a stronger machine.  Atlas and Peco both make twin-coil machines for their turnouts, and they are NOT interchangeable without some effort.  You could remove the Peco spring and then drive either turnout with a Tortoise or other stall motor machine.

I have not heard otherwise, so it appears that MTH will not be around this time next year, so you may have trouble getting MTH locomotives or electronics.  Unless you have a lot invested in MTH items, you might want to consider moving entirely to DCC.

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

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Posted by rrinker on Thursday, November 26, 2020 6:44 PM

 As can generic servos, or Tortoise machines. 

It's not a matter of overcoming the spring - it's more of a "do you want slow motion operation" because if you leave the spring in place and use a servo or a Tortoise, the points will snap over just like with a solenoid motor thanks to the spring. For the slow motion machine to move them smoothly and slowly, they have to be free, like Atlas points. The Peco ones are easily removable - on the Code 83 stuff at least, they are removable and replaceable from the top, so if you change your mind you don't have to rip up the turnout to take the spring out or put it back in. 

                               --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 richhotrain on Thursday, November 26, 2020 6:52 PM

Lastspikemike

Walthers layout system switch motors can also overcome the springs in Peco or ME turnouts. 

rrinker

 As can generic servos, or Tortoise machines. 

Yep, if your finger can flip the spring loaded points, then so can servos and Tortoises.

Rich

Alton Junction

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Posted by SeeYou190 on Friday, November 27, 2020 10:19 AM

What would be the purpose of using a stall-motor switch machine and leaving the Peco throwbar spring in place?

It seems unnecessary, would eliminate the slow-motio action of the switch machine, and introduce another possible cause of failure.

-Kevin

Living the dream.

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Posted by rrinker on Friday, November 27, 2020 12:40 PM

 Some people don't like to alter their turnouts. It's not going to hurt anything, it just turns a slow motion stall motor into a stall motor solenoid - the points will snap like they do with a solenoid machine but you still have the ease of wiring the stall motor (simple toggle, no pushbuttons, and no chance to burn it out if the button should stick, and extra contacts for signals and/or frog power).

                                  --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 SeeYou190 on Friday, November 27, 2020 1:43 PM

rrinker
It's not going to hurt anything, it just turns a slow motion stall motor into a stall motor solenoid - the points will snap like they do with a solenoid machine

I guess. It just seems silly to defeat the smooth operation of a Tortoise point motor.

-Kevin

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Posted by jjdamnit on Friday, November 27, 2020 2:58 PM

Hello All,

If you are going to use PECO side mounted solenoid turnout motor (PL-11) keep in mind the color coding on the PECOs differ from the Atlas solenoid motors. 

The Atlas color coding is the poles are Red & Green and the neutral is Black. 

PECO color coding is the poles are Red & Black and the neutral is GREEN!

Because of the high tension of the spring on the PECO turnouts, if the turnout and PL-11 turnout motor are both not securely attached to a solid base, the throwbar on the turnout motor will jump off the pin on the throwbar of the turout because the pin has a rounded top.

To secure this connection I tapped a 0-80 hole in the pin of the throwbar on the turnout.

I then used a 0-80 nut, bolt, and washer to fasten the pin to the throwbar of the turnout motor.

Hope this helps.

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

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Posted by richhotrain on Friday, November 27, 2020 5:05 PM

Lastspikemike
 
richhotrain 
Lastspikemike

Walthers layout system switch motors can also overcome the springs in Peco or ME turnouts.  

rrinker

 As can generic servos, or Tortoise machines.  

Yep, if your finger can flip the spring loaded points, then so can servos and Tortoises. 

Rich 

Or maybe not. Possibly depends on the length of the operating wire? 

https://tonystrains.com/news/using-the-tortoise-with-peco-turnouts/

Length? Do you mean the diameter of the wire on the Tortoise. I use 0.039" piano wire. Plenty strong enough.

Rich 

 

 

 

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Posted by SeeYou190 on Friday, November 27, 2020 5:47 PM

jjdamnit
The Atlas color coding is the poles are Red & Green and the neutral is Black.  PECO color coding is the poles are Red & Black and the neutral is GREEN!

That is an important point.

When we were building Randy's N scale NORFOLK SOUHERN layout with some Atlas and many Peco switch machines, the confusion was real.

-Kevin

Living the dream.

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Posted by rrinker on Friday, November 27, 2020 10:27 PM

 Peco Code 83 springs come out and go back in intact, there's no snipping anything. And I've done it to one of mine, completely fromt he top side, not lifting the turnout off the workbench, as if it were actually installed on a layout. It's not as easy to put back in as it is if you cna pick the whole turnout up, but it can be done. And no snipping off - just save the old spring and put it back.

 Maybe the Code 100 ones are different.

                           --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 richhotrain on Saturday, November 28, 2020 1:06 AM

rrinker

 Peco Code 83 springs come out and go back in intact, there's no snipping anything. And I've done it to one of mine, completely fromt he top side, not lifting the turnout off the workbench, as if it were actually installed on a layout. It's not as easy to put back in as it is if you cna pick the whole turnout up, but it can be done. And no snipping off - just save the old spring and put it back.        

Agreed. No snipping, at least on Peco Code 83 springs. One bit of advice. Whether you are removing springs from the turnout or putting them back on, only do it an enclosed room with no carpeting, just a bare wood or stone floor. Smile, Wink & Grin

Rich

Alton Junction

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Posted by MisterBeasley on Saturday, November 28, 2020 10:20 AM

richhotrain

Agreed. No snipping, at least on Peco Code 83 springs. One bit of advice. Whether you are removing springs from the turnout or putting them back on, only do it an enclosed room with no carpeting, just a bare wood or stone floor. Smile, Wink & Grin

 

Rich

Would the same trick used with Kadee coupler springs work?  Run a piece of thread through the spring to retain it, and then remove the thread once the spring is in place.

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

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Posted by rrinker on Saturday, November 28, 2020 2:07 PM

 I've heard of that one before. SHould work. I just use the blade of a #2 knife to fit in the knuckle springs. Once both ends are hooked over the pegs, the blade can be withdrawn without popping the spring back off.

                                --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 SeeYou190 on Sunday, November 29, 2020 11:28 AM

MisterBeasley
Would the same trick used with Kadee coupler springs work?  Run a piece of thread through the spring to retain it, and then remove the thread once the spring is in place.

When I moved my workbench out of the spare bedroom a few weeks ago, there was a spot behind the leg in the corner where I could never reach with a broom.

I inspected what had collected there hoping for some long lost treasures.

There were about 30 Kadee knuckle springs. Now I know where they all went.

-Kevin

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Posted by richhotrain on Sunday, November 29, 2020 5:33 PM

MisterBeasley
 
richhotrain

Agreed. No snipping, at least on Peco Code 83 springs. One bit of advice. Whether you are removing springs from the turnout or putting them back on, only do it an enclosed room with no carpeting, just a bare wood or stone floor. Smile, Wink & Grin

Rich 

Would the same trick used with Kadee coupler springs work?  Run a piece of thread through the spring to retain it, and then remove the thread once the spring is in place.

Dunno, maybe, but I prefer a "panic room" with nothing in it, nothing, so I can find those darn runaway springs.

Rich

Alton Junction

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