starman If I use a turnout, I will have to switch the turnout each time the train comes out of the loop. I am hoping I won’t have to do that.
not sure why you question the use of a turnout? Of course you'll need one since the track loops back to itself. And you'll need to switch the turnout after the train enters the loop. Are you thinking the turnout can be switched automatically?
typical dogbone
greg - Philadelphia & Reading / Reading
Hello all,
the only way to avoid a turnout or switch is to create a dual track main between the two ends of the bone.
This will eliminate the need for an auto-reversing unit as the polarity remains the same through out the track loop.
Other than that, there is no way to avoid switches and an auto-reversing unit.
Don't forget the gaps for the AR unit.
You can automate the switching actions by using detection units but that will add cost and complexity to the wiring of your pike.
Also, you did not mention if you are using DC or DCC. With DC you can activate the switch and the polarity with a Double Pole Dual Throw switch.
Hope this helps.
"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"
gregc starman If I use a turnout, I will have to switch the turnout each time the train comes out of the loop. I am hoping I won’t have to do that. not sure why you question the use of a turnout? Of course you'll need one since the track loops back to itself. And you'll need to switch the turnout after the train enters the loop. Are you thinking the turnout can be switched automatically? typical dogbone
I was hoping I could switch the turnout automatically, but perhaps that is not possible.
Yes, you can switch the turnout and the polarity automatically.
Again, are you using DC or DCC?
If you are using DC Atlas makes units that will switch the turnout and the polarity automatically. Snap Relays.
As I said before this will add complexity and cost to your layout.
If you are using DCC automatic switching and polarity reversing can be accomplished. Again, with additional cost and complexity.
starman, my question to you is, why don't you just add a second mainline?
This will decrease complexity and cost no matter what system you use.
The cost of the extra track will be significantly less than adding automation to your pike.
Your choice.
The solution you are seeking can be done through automation and cost.
Post Script: I suggest you get the Atlas Complete Wiring Book. This primarily deals with DC wiring but has applications and concepts the are pertinent to DCC applications. Also, Kalmbach Publishing has several DCC specific books that can help you in your track plan and wiring decisions.
H.T.H.
The PSX-AR will handle your polarity reversing and automate the turnout for you.
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
carl425 The PSX-AR will handle your polarity reversing and automate the turnout for you.
If you are willing to jump onto the Arduino train, reversing loops (and most anything else) can be done quite easily and cheaply!
Please let us know which solution you decided on and keep us informed on your progress.
Thanks for sharing.
Link to PSX-AR.
I second the use of the PSX-AR. Very easy to use.
Neal
i'm curious, how does the PSX control the turnout?
The switch machine is wired directly to the PSX-AR. When the PSX-AR detects a short at one of the gaps at the end of the reverse loop, it throws the switch and reverses the track polarity. The engine just keeps moving through the switch like nothing happened.
PSX-AR instructions.
aren't the gaps on the diverging side (loop) side of the turnout. I can see how this works when the train is exiting the loop, if the turnout switches quickly.
But what about a train entering the loop. won't it be over the turnout? Or is it expected that the turnout is only controlled by the reverser? that a train will enter the loop through the same turnout position it last exited the loop?
gregca train will enter the loop through the same turnout position it last exited the loop?
Yes.
The polarity is always correct for the direction the turnout is aligned. Left alone, every other trip through the loop will be in the opposite direction.
There is also an option to manually reverse the loop. This will also throw the turnout so you can go around in the other direction.
There are gaps at the main route and diverging route. The polarity of the loop track is controlled by the PSX-AR.
You have not said how big the layout will be or the radius of the loops.
Is this a shelf layout?
A stand alone pike?
Will this be a walk around or against a wall?
Is this a display that is autonomous or will a person be operating the pike?
All good things to know.
One other thing to consider; with the single track main, is that the loops on the ends of the dog bone will determine the maximum length of the train.
Also, the radius of the track can also limit the type of motive power and rolling stock.
An 18-inch radius might limit you to 4-axle diesels, 0-4-0 and/or 0-6-0 steamers and a maximum of 50-foot rolling stock.
Please keep us in "the loop" so to speak!
For those who are interested, I have decided to simplify things by rearranging my pike so I can run a double main line. I actually have enough track on hand to do this and it will eliminate the need for me to have reversing loops, not to mention saving dollars!
My pike takes up a basement room that is 19' by 13'. I am attempting to model the Norfolk and Western coal operation of the 1950's from western Virginia to the Lambert's Point yard in Norfolk, Virginia. I have a 24" wide shelf on 3 walls and part of 1 wall. The ends of the shelves flair out to accommodate about a 30” radius track. I also have a 5' wide peninsula running down the center of the room. On the peninsula will be my interpretation of the Norfolk and Western Lambert's Point yard where coal from western Virginia is loaded onto colliers for sea transport to other ports. (I grew up just a few miles from the Lambert's Point yard.)
If all goes as planned, I should have about 130' of main line circling the entire pike. My smallest radius will be about 30”. I am using DigiTrax. We have an N&W J Class engine, 2 other steam engines, and several early diesel engines, plus an assortment of rolling stock. The J Class and the other steam engines have already been converted to DCC. Hopefully the diesels will be converted soon.
My son and I are building this pike mainly for his children (7 & 5). My son remembers the simple pike my father had when my son was young and has always wanted his own pike. I have the room so we are building the pike in my basement. My son lives very close by.
starman For those who are interested, I have decided to simplify things by rearranging my pike so I can run a double main line. I actually have enough track on hand to do this and it will eliminate the need for me to have reversing loops, not to mention saving dollars! ...snip...
...snip...
Keep in mind that if you install any crossovers in your double track mainline you will create a 'reversing' section. It's not a problem, but you're back to needing a PSX-AR (or similar).
Modeling an HO gauge freelance version of the Union Pacific Oregon Short Line and the Utah Railway around 1957 in a world where Pirates from the Great Salt Lake founded Ogden, UT.
- Photo album of layout construction -
Onewolf starman For those who are interested, I have decided to simplify things by rearranging my pike so I can run a double main line. I actually have enough track on hand to do this and it will eliminate the need for me to have reversing loops, not to mention saving dollars! Keep in mind that if you install any crossovers in your double track mainline you will create a 'reversing' section. It's not a problem, but you're back to needing a PSX-AR (or similar).
starman For those who are interested, I have decided to simplify things by rearranging my pike so I can run a double main line. I actually have enough track on hand to do this and it will eliminate the need for me to have reversing loops, not to mention saving dollars!
In fact, that is exactly what he should do to increase the capacity for running more than one train at a time. My layout is a double mainline with crossovers at various points to enter/exit yards and spurs and sidings. No reverse loops on my double mainline.
Rich
Alton Junction
As for your automatic-switch question, spring switches could be an option. They're not electrically operated, so that would save you some of the headache in wiring your layout.
Just some thoughts.
richhotrain Not necessarily. If he turns his drawing into a double mainline dogbone, he can exit the end loops onto the other mainline and then add a crossover from one mainline to the other mainline mid way between the ends of the layout and wire everything including the crossover in phase - - no reverse loops. In fact, that is exactly what he should do to increase the capacity for running more than one train at a time. My layout is a double mainline with crossovers at various points to enter/exit yards and spurs and sidings. No reverse loops on my double mainline. Rich
Not necessarily. If he turns his drawing into a double mainline dogbone, he can exit the end loops onto the other mainline and then add a crossover from one mainline to the other mainline mid way between the ends of the layout and wire everything including the crossover in phase - - no reverse loops.
Hmmm. I'm no expert but it seems me that this crossover configuration produces the need for a reversing section (in the blue circle)? Are you referring to a different crossover configuration?
Onewolf Hmmm. I'm no expert but it seems me that this crossover configuration produces the need for a reversing section (in the blue circle)? Are you referring to a different crossover configuration?
Your drawing is not actually a double main line, but rather a continuous single mainline running around the entire layout. A true double main line provides all kinds of options for maintaining and/or changing the direction of multiple trains.
richhotrainA true double main line provides all kinds of options for maintaining and/or changing the direction of multiple trains. Rich So if I have a true double main line (after rearranging my pike I can have two main double lines), what would I need to do to be able to switch from one double main line to the other double main line and have trains on both lines going in the same or opposite directions?
So if I have a true double main line (after rearranging my pike I can have two main double lines), what would I need to do to be able to switch from one double main line to the other double main line and have trains on both lines going in the same or opposite directions?
Rich,
I'm pretty sure OP Starman is planning to have two return loops connected by a "double track" mainline (aka DogBone). It's a very popular configuration for good reason. I just wanted to point out that adding a crossover along the double track mainline introduces a reversing section (albeit with the addition of better operation potential).
Doug
This illustrates how hard it is to understand or solve track problems when the poster doesn't post a picture.
As noted model railroader Allen Greenspan said;
As long as a crossover doesn't go through the center of the circle (or dogbone), we don't have a reversing loop.
Henry
COB Potomac & Northern
Shenandoah Valley
Onewolf Rich, I'm pretty sure OP Starman is planning to have two return loops connected by a "double track" mainline (aka DogBone). It's a very popular configuration for good reason. I just wanted to point out that adding a crossover along the double track mainline introduces a reversing section (albeit with the addition of better operation potential). Doug
starman richhotrain A true double main line provides all kinds of options for maintaining and/or changing the direction of multiple trains. Rich So if I have a true double main line (after rearranging my pike I can have two main double lines), what would I need to do to be able to switch from one double main line to the other double main line and have trains on both lines going in the same or opposite directions?
richhotrain A true double main line provides all kinds of options for maintaining and/or changing the direction of multiple trains. Rich So if I have a true double main line (after rearranging my pike I can have two main double lines), what would I need to do to be able to switch from one double main line to the other double main line and have trains on both lines going in the same or opposite directions?
Thank you for the update with further details.
Sounds like you have a great project ahead with your son and grand kids.
Take a look at this track plan from Atlas. http://shop.atlasrr.com/p-44219-ho-21-the-waterwings-.aspx. You might be able to adapt it to your needs.
This track plan is intended for DC operation hence the Cab Selector.
If you decide to go with the crossover you will need an auto reverser and some form of switch control.
The switch controls can be automated; with detection circuits, it can be wired DCC; controlled through the DigiTrax controller, DC; with two remote switches, or can be manually thrown.
The manual throws would be the cheapest option but with little hands might not be the best option.
When I converted my pike from DC to DCC I kept the turnouts DC. I have a Wye in the center of my loop that requires the use of an AR unit.
This combination works well for me.
Again, thanks for the update and good luck with the project.