# About Turnouts



## Bkubiak (Oct 20, 2013)

I have 5 turnouts, all brass and all made in Yugoslavia and all have switch motors and they all work.

That said here are some of my issues and questions.

Sometimes for no apparent reason cars and sometimes loco's will just derail going over them.

Once in a while a loco will just stop on them

The screw heads that attach the switch motor to the track sit higher up then the rail, some diesel plows strike them and some car truck spring bottom hits them.

I am thinking to replace them with Silver rail stuff, Don't wish to break the bank and will look to eBay, what brand or features shall I look for?


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## DonR (Oct 18, 2012)

I'm the Peco nut here. I have about 20 or so of them and
neither cars nor locos derail on them unless the switchman
was in his cups and failed to give a clear track.

Get the INSULFROG Pecos. They are very well made and
I have never had any trouble with them, NONE.

One word of caution tho. They will not be a direct
replacement for any other make. The dimensions
are slightly different. You would have to slightly
realign your tracks.

Another word: Insulfrog Pecos are power routing. That
means that if you have the points set for straight, the
power will be off to the diverting track. It may be necessary
to add a track drop or two depending on your layout.

Don


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## MtRR75 (Nov 27, 2013)

I started with in inherited layout that had brass track and turnouts on it -- and had the same problems. Some of the problems were the turnouts, and some were due to the locos. I eventually bit the bullet and ordered nickel silver turnouts. I found that what was more important than the rail material was that the new turnouts were better made. In particular, the points are sturdier and less likely to bend under the weight of the loco. Most of my locos now run fine. I have traced the few remaining problems to loco issues -- some I fixed; at least one is not fixable.

Steam locos are especially prone to problems on turnouts, because of the large drive wheels that don't pivot on curves (like diesels do). The "stopping" is usually due to a short because the steamer drive wheels hit both tracks at the frog momentarily. Sometimes this is just a jerk and the loco gets by it. At slow speeds, the loco is more likely to stop. To get around the problem of 3 to 4 pairs of drivers that are in a line trying to negotiate a curve or a turnout, some makers design the drivers so that some (or all) of the drivers have some left-right play in them -- which allows them to adjust to the curves. Unfortunately, this play also makes it more likely that a driver will sometimes catch both tracks at the frog and short out.

The general rule that some here quote is that 6-driver steamers are usually ok, but-8 driver steamers will be prone to problems on small-radius turnouts. I have found that it is the manufacturing of the specific loco that is more important. I have a Bachmann Spectrum 2-8-0 that runs fine on 18" curves and new Atlas snap switches (the turnouts that are most likely to have problems). The reason is that the driver wheels have modest left-right play and are pretty thin -- which avoids the problem of the wheels contacting both rails at the frog. I also have an IHC 4-6-0 which has too much left-right play in the driver wheels and the wheels are rather thick, both of which make it easier for a driver wheel to catch both rails at the frog. It shorts out about half of the time that I run it. There is nothing I can do about it.

One important thing to keep in mind when changing turnouts: If your nickel-silver turnouts are not the same style from the same maker as your brass turnouts, you will have to make major changes to the track that is attached to the turnouts.


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## Bkubiak (Oct 20, 2013)

MtRR75 said:


> I started with in inherited layout that had brass track and turnouts on it -- and had the same problems. Some of the problems were the turnouts, and some were due to the locos. I eventually bit the bullet and ordered nickel silver turnouts. I found that what was more important than the rail material was that the new turnouts were better made. In particular, the points are sturdier and less likely to bend under the weight of the loco. Most of my locos now run fine. I have traced the few remaining problems to loco issues -- some I fixed; at least one is not fixable.
> 
> Steam locos are especially prone to problems on turnouts, because of the large drive wheels that don't pivot on curves (like diesels do). The "stopping" is usually due to a short because the steamer drive wheels hit both tracks at the frog momentarily. Sometimes this is just a jerk and the loco gets by it. At slow speeds, the loco is more likely to stop. To get around the problem of 3 to 4 pairs of drivers that are in a line trying to negotiate a curve or a turnout, some makers design the drivers so that some (or all) of the drivers have some left-right play in them -- which allows them to adjust to the curves. Unfortunately, this play also makes it more likely that a driver will sometimes catch both tracks at the frog and short out.
> 
> ...


All my track is Atlas either flex or sections and code 100


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## MtRR75 (Nov 27, 2013)

I looked at your layout picture that you posted under the Spectacular 4 x 8 Layouts thread. I can only see two of your turnouts. They appear to be older Atlas Snap switches (like I had). I replaced mine with the newest versions because I did not want to alter my track plan. The new ones will fit in where the old ones are now. Besides changing from brass to nickel silver the newest versions have several other improvements over the older ones.

(1) The rivets at both ends of the points have been replaced with a more secure attachment mechanism. Strangely there was a time when this improvement was only made at the moving ends of the points. Later both ends were updated. The rivets would loosen over time, allowing the points to sag, increasing derailments.
(2) The points are made of a thicker metal -- so that they do not bend under the weight of the loco.
(3) The new turnouts have notches in the side rails where the points set into. This decreases derailments caused by incoming cars slicing in between the points and the rails.

These improvements were made some time after the switch from brass to nickel silver, which means that you want to be sure that you get the newest versions. Back in the 1990s when our kids were into trains, all of the turnouts that we got were nickel silver, but had none of the other improvements. When I started redoing all of the track in my inherited layout last year I got most of my turnouts on ebay, but I was careful to check the pictures to be sure that I could see that the rivets had been replaced at BOTH ends of the points. There are quite a few New Old Stock turnouts out there -- advertised as new (never opened), but which still have the rivets.

You can also save money by buying the manual snap switches instead of the powered ones. The switch machine from your old turnout will fit onto the new turnouts. All but one of the switch machines that came with my old brass layout still work.

As for the loco hitting the screws on that hold the switch machine in place, Atlas snap switches come with a small extender piece of plastic that you insert in between the switch machine and the turnout. This pushes the switch machine about a quarter of an inch farther away from the track to avoid that problem. (You insert the working part of the switch machine into the OTHER hole in the throw bar.) If you get new snap switches you will get that piece, too -- even with the manual turnouts. If you choose to stay with your current turnouts, I can send you a few of those adaptors. I have a pile of them -- more than I will ever need. Just PM me.

On the other hand, you could also solve the problem of the loco hitting the screws by simply removing the screws. The switch machine snaps into the turnout and should not move unless there is damage to the snapping mechanism or you bump into it fairly hard.


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## Bkubiak (Oct 20, 2013)

MtRR75 said:


> I looked at your layout picture that you posted under the Spectacular 4 x 8 Layouts thread. I can only see two of your turnouts. They appear to be older Atlas Snap switches (like I had). I replaced mine with the newest versions because I did not want to alter my track plan. The new ones will fit in where the old ones are now. Besides changing from brass to nickel silver the newest versions have several other improvements over the older ones.
> 
> (1) The rivets at both ends of the points have been replaced with a more secure attachment mechanism. Strangely there was a time when this improvement was only made at the moving ends of the points. Later both ends were updated. The rivets would loosen over time, allowing the points to sag, increasing derailments.
> (2) The points are made of a thicker metal -- so that they do not bend under the weight of the loco.
> ...


This is all great information, do the newer old stock turn outs that I see advertised on Ebay have a particular model number I should look for to be sure I get some with all the improvements?

Yes on the layout I only have two turnouts installed but I plan to install one on either end of the mainline that runs under the bridge, that will give me a siding on either side of that mainline to park rolling stock on, I already cut out the riser section while I was replacing some of the 18R curves with 22R, I will take and post some pictures of the construction tomorrow I have a few other areas I need construction advice on 

Funny thing happens once in a while on a straight section of 3ft flex track, in the middle of the track the engine just stops running as if the power was cut off, which it was, and a few seconds later when the red power light comes on and the power pro lights back up all I have to do is touch the button and the loco starts back up again, this is in DCC.


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## Bkubiak (Oct 20, 2013)

About the numbers of turnouts #4 # 6 etc hat does that mean, is it the radius of the turnout?

And what about turnouts on a bend, what issues do you encounter there????


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## Bkubiak (Oct 20, 2013)

Bkubiak said:


> About the numbers of turnouts #4 # 6 etc what does that mean, is it the radius of the turnout?
> 
> And what about turnouts on a bend, what issues do you encounter there????


there should be a glossary to help us newbies to all the slang and shortcuts to model railroading to help us understand the codes the numbers of rails turns the radius of rails etc etc and etc


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## Bkubiak (Oct 20, 2013)

Can anyone tell me what the code for this turnout is

ebay item 281668519213

http://rover.ebay.com/rover/0/e1105...em=281668519213&ssPageName=ADME:X:AAQ:US:1123


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## MtRR75 (Nov 27, 2013)

Bkubiak said:


> Can anyone tell me what the code for this turnout is
> 
> ebay item 281668519213
> 
> http://rover.ebay.com/rover/0/e1105...em=281668519213&ssPageName=ADME:X:AAQ:US:1123


Something is wrong with this link. Clicking on it sends me to the ebay home page.


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## Bkubiak (Oct 20, 2013)

MtRR75 said:


> Something is wrong with this link. Clicking on it sends me to the ebay home page.


HMMM Just get on eBay and type in that item number, that should work

When I increased the radius of the upper level to 22R I had to make a platform for the track that extends slightly out and over the lower track, as you can see I was thinking to make a sort of tunnel and put vegetation and what not on it but I think it looks weird and welcome suggestions from the experts

As far as the track that runs under the bridge I plan to install a turn out at either end so I can have side tracks to keep rolling stock on I took a few pictures to give an idea what I am thinking


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## MtRR75 (Nov 27, 2013)

Unfortunately, Atlas did not change the model numbers of the snap switch turnouts when they made the improvements. The numbers for all of the nickel silver versions are:

#850 = Left Powered
#851 = Right Powered
#860 = Left Manual
#861 = Right Manual

The brass turnouts may have had different numbers -- I inherited mine -- without packaging. They are, however, the same shape as the nickel silver ones.

Below are powered brass snap switches showing the rivets at both ends of the points (red circles). The early nickel silver turnouts were identical to these -- rivets at both ends, but I don't have a picture of them. 








Below are powered nickel silver snap switches showing SOME improvement. Note that the throwbar end of the points has an improved attachment. However, the pivot end of the points still has the rivets. Also the point rails are still very thin and easily bent. The yellow circle shows the brass fittings on the turnout motor -- where the screws and wires are attached. This indicates that these are powered turnouts.








Below is the newest version of the Atlas snap switch -- this is a right manual turnout. Note that the rivets have been replaced at BOTH ends of the points. Also, the points are thicker and less easily bent. If you look closely, you can also see that there are indentations in the side rails where the points fit in. The yellow circle shows that there are no brass fittings on the turnout machine. This means that this is a manual turnout. But there is no difference in the turnout itself. You can attach a motorized turnout machine from another turnout to this turnout, and it becomes a powered turnout.








Hope this helps/


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## CTValleyRR (Jul 26, 2014)

Bkubiak said:


> there should be a glossary to help us newbies to all the slang and shortcuts to model railroading to help us understand the codes the numbers of rails turns the radius of rails etc etc and etc


You can search any of those topics here, or any basic book on model railroading has this information.


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## MtRR75 (Nov 27, 2013)

Bkubiak said:


> About the numbers of turnouts #4 # 6 etc hat does that mean, is it the radius of the turnout?
> 
> And what about turnouts on a bend, what issues do you encounter there????


Atlas makes two types of turnouts = Snap Switchers and Custom Line Turnouts. Snap switches are the easiest for beginners to use and they are best for tighter curves (i.e. fitting more track into a small place). They come with a switch machine (manual or powered). The turned-out branch of the turnout is approximately 2/3 of an 18" radius curve section. They come with an additional 1/3 curve to allow you to complete the curve section, but this is optional.

On custom Line turnouts, the turned-out branch becomes straight track, once the diversion is completed. This means they take more space to use, but they also will accommodate larger locos and are less prone to derailments. The numbers (#4, #6, etc.) indicate the angle between the two branches of the turnout. #4 is the widest angle (but still less than the Snap Switch), #6 is narrower, etc. (The number indicates a specific geometric arrangement, but I can't remember exactly what it is -- perhaps someone else will provide that info.) Custom Line turnouts do not come with a switch machine. You have to buy them separately (or use your fingers to flip the turnouts).

The ebay link you posted is an older Custom Line turnout -- note the rivets at both ends of the points. I would avoid that.

If you are going to switch out turnouts, you first need to be sure of exactly what you have, so that you can match the shape, if possible. All of my turnouts (brass and nickel silver) say Atlas Snap Switch on the bottom.  The brass ones do not say where they were made. Some of the older nickel silver ones say made in China. None say made in Yugoslavia. Are you sure that yours are Atlas?

Some have suggested that you use Peco turnouts. I have no personal experience with them, but they do get universally great reviews, so they are worth considering. They are more expensive than Atlas turnouts. But I have been told (by a company rep.) that Peco makes footprint diagrams of their turnouts available on their website, so you can print them out, cut them out, and try them for size in our layout.


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## CTValleyRR (Jul 26, 2014)

Bkubiak said:


> About the numbers of turnouts #4 # 6 etc hat does that mean, is it the radius of the turnout?
> 
> And what about turnouts on a bend, what issues do you encounter there????


It's not the radius of the turnout. Atlas Snap Switches, which are designed to be used with an oval of track, have a diverging leg which is a 20 degree arc of 18" or 22" curve (the turnouts are marked which is which).

Most other brands of turnout use the standard terminology where the number is linear units over diverging units. In normal speak, a #4 turnout diverges one unit of length for every 4 it goes forward (so if the leg is 2" long, it diverges 1/2"), but it's a straight leg, not an arc.

One problem you will have is that every turnout model, just about, has a different geometry. Even two #4 turnouts are not the same, unless they are the exact same model. Even if you buy new Snap Switches, they may not be exactly the same as your old ones.

For turnouts on a curve (I assume that's what you mean by bend), a curved turnout is usually your best bet. While these are often identified by number, the manufacturer will usually also identify the inside and outside radii. Unless you can put in a length of straight track longer than your locos between the curve and the turnout, it's basically like having a kink in your track.


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## CTValleyRR (Jul 26, 2014)

And that stall on straight track? Is it one spot in the track where everything stalls, or one loco that stalls on straight track? Clean your rails carefully and make sure you don't have a spot of something on your rails, and check for anything which may be sticking up and shorting across the rails when the train goes by (foam pins are notorious culprits).


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## MtRR75 (Nov 27, 2013)

Bkubiak said:


> And what about turnouts on a bend, what issues do you encounter there????


No problem having curved track attached to either or both ends of a turnout. But the curve must be in the same direction as the turnout curve. If you switch curve direction, you get an S curve -- and more derailments (this applies for ordinary track too). You need a straight section between changes in curve direction -- about the length of your longest car or loco.

If you mean substituting a turnout for a curved section of track on an existing layout, you can do that, too. But you will have to change the position of the adjacent track, because almost all turnouts have a straight section at one end. Peco does make a double curved turnout that can be substituted for a curved section, but I think the radii are pretty large.


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## CTValleyRR (Jul 26, 2014)

MtRR75 said:


> No problem having curved track attached to either or both ends of a turnout. But the curve must be in the same direction as the turnout curve. If you switch curve direction, you get an S curve -- and more derailments (this applies for ordinary track too). You need a straight section between changes in curve direction -- about the length of your longest car or loco.
> 
> If you mean substituting a turnout for a curved section of track on an existing layout, you can do that, too. But you will have to change the position of the adjacent track, because almost all turnouts have a straight section at one end. Peco does make a double curved turnout that can be substituted for a curved section, but I think the radii are pretty large.


Ooops. That's what I meant. I was THINKING "opposite direction", but it didn't come out of my fingers....


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## MtRR75 (Nov 27, 2013)

CTValleyRR said:


> And that stall on straight track? Is it one spot in the track where everything stalls, or one loco that stalls on straight track? Clean your rails carefully and make sure you don't have a spot of something on your rails, and check for anything which may be sticking up and shorting across the rails when the train goes by (foam pins are notorious culprits).


One other possibility. Look at the track from the side. Is it absolutely flat? It can be sloped for an incline, but you can NOT have a sudden transition between horizontal and sloped -- especially with steamers. You need a very gradual transition from level to a slope. If the change is too abrupt, and if the steamer's electrical pickup is one of the middle drivers, it is possible that that driver winds up suspended in air momentarily, leading to a loss of power.


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## MtRR75 (Nov 27, 2013)

One more comment about your turnouts and Atlas Snap Switch turnouts.

I noticed in your most recent photos that the switch machine that you have is not the same as the Atlas ones that I have (which are almost identical to those in the photos that I posted). I also noticed that one of the photos the I put up (harvested from ebay) shows one turnout with an Atlas switch machine and the other with the same switch machine that you have.

This means that either:
(1) You have an older style of Atlas switch machine that I have never seen before, or
(2) Your switch machines (and perhaps your turnouts) are imitations of Atlas products produced by another company a long time ago.

This means that:
(1) My earlier suggestion about moving switch machines to newer turnouts may or may not work for you -- depending on the mounting mechanism, and
(2) If your turnouts are not by Atlas, you may have adjustment issues even with new Atlas snap switches.

P.S. I like the idea of the tunnel to fix your "stacked track" problem.


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## Bkubiak (Oct 20, 2013)

I re-read the eBay ad very carefully for that turnout and realized that the seller said everything he had was pre year 2000, he was asking 10.00 each for those turnouts I found another ad by typing in switch track instead of turnout track which has Brand new Atlas turnouts with a switch motor, they said, and it even has the notch you said to look for that the points will rest into for 10,00 each. I just wrote and asked if they offered a deal on 4 pieces, waiting to hear back right now

Their item number on eBay is 311351034511 I want to be sure it is the correct one..

All my track is Atlas code 100 snap track both flex and sections, I have no idea what snap track means, nothing snaps together the brass turn out's just say Yugoslavia on the bottom


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## MtRR75 (Nov 27, 2013)

Bkubiak said:


> Yes on the layout I only have two turnouts installed but I plan to install one on either end of the mainline that runs under the bridge, that will give me a siding on either side of that mainline to park rolling stock on,


One more thought (I keep thinking of things)...

I went back and looked at your layout picture that showed the two installed turnouts. Since they are on the same straight section of track and link to a short parallel siding, you could use almost any pair of code 100 nickel-silver turnouts. (But I still recommend getting the newest version of Atlas turnouts or Peco for all of the reasons discussed earlier.) The only adjustments that you would have to make would be (1) to shorten or lengthen straight sections on either end of both turnouts, and (2) adjust the length of the siding and its distance from the main line.

But because the additional, planned turnouts would be on a curve, you would need to address the geometry similarity issue for those turnouts. So you could buy two new turnouts, try them on the curved track. If you can't make them work there, you could use them to replace the two that are already installed, This assumes that you need 1 left and 1 right in both places. If not, buy just one and try it first on the curve.


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## MtRR75 (Nov 27, 2013)

Bkubiak said:


> I re-read the eBay ad very carefully for that turnout and realized that the seller said everything he had was pre year 2000, he was asking 10.00 each for those turnouts I found another ad by typing in switch track instead of turnout track which has Brand new Atlas turnouts with a switch motor, they said, and it even has the notch you said to look for that the points will rest into for 10,00 each. I just wrote and asked if they offered a deal on 4 pieces, waiting to hear back right now
> 
> Their item number on eBay is 311351034511 I want to be sure it is the correct one..
> 
> All my track is Atlas code 100 snap track both flex and sections, I have no idea what snap track means, nothing snaps together the brass turn out's just say Yugoslavia on the bottom


The turnouts in the above ebay reference are the newest style. They are MANUAL -- no electrical hookup. You will have to use your existing switch machines or move them manually. The ebay auction is only for the RIGHT snap switch. Make sure that you get the correct number of right and left switches for your needs.

The term Snap Track is what Atlas uses for their sectional track. Their Snap Switch is the turnout designed to go with their Snap Track. As explained earlier, it has a different geometry than Atlas's other turnouts. Originally. Atlas sold some black plastic links that could be snapped onto the ties at the ends of snap track sections and turnouts -- a quick way to hold track together for temporary layouts and for kids that have no patience for roadbed and track nails. (The rail joiners would still hold the track in alignment; the plastic links kept it from coming apart.)

We tried those links when the kids were young. Sometimes they worked, sometimes they required excessive pressure to get them to lock in and forced the track to kink up or down and not lay flat. We gave up and just kept tightening the rail jointers and using small twist ties to keep troublesome junctions together.

P.S. That is a good price for those turnouts


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## Bkubiak (Oct 20, 2013)

MtRR75 said:


> One more thought (I keep thinking of things)...
> 
> I went back and looked at your layout picture that showed the two installed turnouts. Since they are on the same straight section of track and link to a short parallel siding, you could use almost any pair of code 100 nickel-silver turnouts. (But I still recommend getting the newest version of Atlas turnouts or Peco for all of the reasons discussed earlier.) The only adjustments that you would have to make would be (1) to shorten or lengthen straight sections on either end of both turnouts, and (2) adjust the length of the siding and its distance from the main line.
> 
> But because the additional, planned turnouts would be on a curve, you would need to address the geometry similarity issue for those turnouts. So you could buy two new turnouts, try them on the curved track. If you can't make them work there, you could use them to replace the two that are already installed, This assumes that you need 1 left and 1 right in both places. If not, buy just one and try it first on the curve.


I don't think I will get those curved turnouts I will just splice the #4 ones you saw advertised where the track straightens out, that will give almost a 5 ft long siding on other side of that mainline
and
I will replace those two that you currently see on the layout and I'll bet I can sell off the 5 brass turnouts I have on eBay for 3 or 4 bucks each

Snap track is kinda misleading to a newbie, made me think that they somehow snapped together

Ok I ordered the Atlas snap track turnouts, now all my track is Atlas code 100 nickle silver


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## CTValleyRR (Jul 26, 2014)

Interesting. I always thought the term Snap Track derived from users snapping their fingers and saying, "Gee, I wish I'd used flextrack instead." 

Any progress on that dead spot on the straightaway?


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## Bkubiak (Oct 20, 2013)

CTValleyRR said:


> Interesting. I always thought the term Snap Track derived from users snapping their fingers and saying, "Gee, I wish I'd used flextrack instead."
> 
> Any progress on that dead spot on the straightaway?


No Did not get a chance to fool with it today, But I got a clean bill of health from my Cardiologist once they got done trying to kill me today. I was told my shortness of breath when doing anything and my general feeling of tiredness is due to me being out of shape and she actually 
emailed me a Px for a workout on my wife's Treadmill

She said my diet is fine just keep doing what I have been doing, she said she could not believe she was looking at a 76 years old heart, and that I had the heart of a 50 year old, How bout dat?

Spent the afternoon with the Echo Model train club setting up their modular display at the Gold Coast Railroad Museum for tomorrows big National Train Day. I will be running trains and keeping little fingers off things they should not be on.

Here are a few more pictures of that small General Live Steam Loco that they are going to restore, seems my thumb got in the way of most of the pictures, these are the good ones.

A volunteer at the museum told me today that all operable equipment at the museum is run by volunteers, no park or museum employees are allowed to run the real trains, the trams, the small scale railroad, or anything that has anything to do with operations like throwing a switch, something about insurance. I do not understand?????


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## traction fan (Oct 5, 2014)

*Turnout (frog) numbers*



Bkubiak said:


> About the numbers of turnouts #4 # 6 etc hat does that mean, is it the radius of the turnout?
> 
> And what about turnouts on a bend, what issues do you encounter there????


Bkubiak:

The numbers you're referring to are called "frog numbers". The frog is the place where four rails of a turnout come very close to each other and the straight and curved routes cross each other. The frog is usually located pretty close to the center of a model turnout. If you stare straight down at it, a rail frog looks a little bit like the green, amphibious animal in mid-jump.
Perhaps that's where the name came from, I'm not sure. 
The frog number is an indication of how sharply one route of the turnout diverges from the other. The number is calculated somewhat like a gradient's percentage (another term you will encounter in this hobby.) A frog number states, how many units of length it takes to diverge one unit sideways. The smaller the frog# the sharper the "turn" away from the straight route. Thus, the #4 turnout diverges more sharply from the main line onto the siding than a #6 turnout does. 
Prototype turnouts don't usually have curved routes. They also use much bigger frog numbers than model ones. A prototype frog might be a #22, or bigger. That means the divergence is much gentler and can be traversed at higher speed, with greater reliability.
Turnouts on a bend, AKA. in the middle of a curve, can be a source of frustration unless
done properly. The curve built into the turnout,(typically 18" radius in an Atlas "snap track"
HO scale turnout.) should match (ideally) or be slightly tighter than the curve it's cut into.
Anytime you change curve radii, or from curved to straight track sharply; you are more likely to have derailments. Changing directly from a right curve to a left curve is the worst.
This is the infamous "reverse curve". Good track planning should locate these nastys, and avoid them wherever possible.
There is an excellent book available from kalmbach.com that explains all this,including railroad terminology, a lot better Than I can online. It' titled "track planning for realistic operation" by John Armstrong. I highly recommend it.

Hope that helps you more than it bores, or confuses you! 

Traction Fan


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## mykfyll (Jun 13, 2015)

I just checked that turnout. Thats a #4 which is basically 18".


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## CTValleyRR (Jul 26, 2014)

mykfyll said:


> I just checked that turnout. Thats a #4 which is basically 18".


Not exactly. Atlas Snap Swiches incorporate a 1/3 length of either 18" or 22" curve on the diverging leg.

True #4 turnouts (any numbered turnout, for that matter) has a straight diverging leg which diverges 1 unit of distance for every x (where x is the turnout number) units of distance forward.

With that clarified, a #4 turnout does impose approximately the same limits on equipment / truck length and operating speeds as an 18" radius curve. I just don't want newcomers thinking that a #4 turnout incorporates a segment of 18" radius.


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## JNXT 7707 (May 5, 2013)

Where does the name "snap switch" come from anyway?

And it's that 1/3 segment of 18" R track that compounds the confusion. When I first saw them I made the assumption it was the equivalent of a section of 18"R track with that added.


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## MtRR75 (Nov 27, 2013)

JNXT 7707 said:


> Where does the name "snap switch" come from anyway?
> 
> And it's that 1/3 segment of 18" R track that compounds the confusion. When I first saw them I made the assumption it was the equivalent of a section of 18"R track with that added.


The Atlas snap switches with the 1/3 segment of 18" radius added, accomplish approximately (but not exactly) a 30° turn which is what an 18" radius piece of sectional track accomplishes. However, the snap switch has a short straight segment (about 1.5") before the curved part begins to diverge from the straight part. So the snap switch can not be substituted for an 18" curved piece of sectional track without making other adjustments to the layout.

One extra tidbit that I figured out. With brass track and the older nickel silver track the snap switches were closer to 27° than to 30°. Also if you put three of the 1/3 curves together, they were 3/4" longer than a standard 18" curve. At some point, somebody at Atlas decided to fix these problems. So the newer snap switch comes with a 1/3 curve that is about 1/4" shorter than the old one, so that three of them do exactly equal an 18" curve. The newer, shorter curve has the same number of ties as the older one. But, they are a little closer together and the 1/3 curve it is curved tighter so that the newer snap switch comes closer to accomplishing a 30° curve. I measured it at about 28.5° to 29°. (But there still is the 1.5" long straight section at the beginning of the turnout.)

Why do I know all of this? I inherited a brass layout that i liked, but had problems with the turnouts and started changing them out to newer ones. When the new turnout did not exactly line up to the track where the old turnout had been removed, I started measuring the pieces carefully.


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## JNXT 7707 (May 5, 2013)

Thanks for the info MtRR75. Interesting stuff. Honestly I was never aware that there was so much variation among manufacturers, or even between old and new.

Still haven't heard why it's called a "snap switch" hwell:


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## Magic (Jan 28, 2014)

I would assume that is because they "snap" into position when you activate the switch. 

Magic


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## highvoltage (Apr 6, 2014)

JNXT 7707 said:


> Where does the name "snap switch" come from anyway?......


Atlas copyrighted the name for some of their products. _"These starter sets are a snap for beginners to assemble. Each contains enough Snap-Track®, Snap-Switches® and components to assemble a 38” x 56” oval layout..."_


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## JNXT 7707 (May 5, 2013)

highvoltage said:


> Atlas copyrighted the name for some of their products. _"These starter sets are a snap for beginners to assemble. Each contains enough Snap-Track®, Snap-Switches® and components to assemble a 38” x 56” oval layout..."_


I knew it had to be marketing


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## Mr. SP (Jan 7, 2015)

*Turnouts*

My railroad is built with Atlas code 100 N/S track and turnouts. The Atlas turnouts require some work to get them to not derail trains. 
Usually it's the points that have to be filed down so the wheel flanges don't pick them and derail the train.
I reworked all my turnouts and now have no derailment problems.


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## tr1 (Mar 9, 2013)

*Snap switch*

It is my opinion the word "snap" either refers to how the motor is connected to the turnout
or the sound the electric motor makes when the dual solenoids are activated.:dunno:
tr1


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## CTValleyRR (Jul 26, 2014)

tr1 said:


> It is my opinion the word "snap" either refers to how the motor is connected to the turnout
> or the sound the electric motor makes when the dual solenoids are activated.:dunno:
> tr1


I doubt it. If you look above, you'll notice that the whole line is named "snap", not just the turnouts. plus the original ones were hand thrown.

It is much more likely thst the name originates from the American slang "snap", meaning easy or rapidly accomplished. See highvoltage's post above.


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## tr1 (Mar 9, 2013)

*derails at turnouts*

I stand corrected, Thank you!
I remember some of those Atlas turnouts had to be slightly modified. This was accomplished by filing the corner down slightly on the pivoting rails that direct the rolling
stock. What railway(path) to take. Straight or diverging on the turnout? This way the truck 's wheels would not derail.I don't know if that was faulty rivets or the very thin metal,that caused the derailment?
Here.the sharp right angels of the dual rail some how, some way, was tripping the wheels on some of the rolling stock trucks. This was filed flater__L =/| no sharp corner
points formed from the 90 degree thinner rail stock.:hah:/ = |_ this right angle here point was filed flatter. I hope I got my point across. Some time I'll add pictures too.
Thank you, tr1


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## tr1 (Mar 9, 2013)

*I'm not an expert,although I may provide some helpful suggestions?*

It's a good idea to always have access to a tunnel area. Because derails do happen, which is also what murphy's law is all about. You can make a plaster mountain in this area, with a
temporary removable plaster cover. The "zip texturing technique" can be used here.
some type of bush lichen could hide the seems that may occur, when you have a temporary
removable cover.in case of a derail. Again......Good luck!


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