# REVERSING LOOP vs CROSSOVER "X"



## gregg k (Dec 27, 2007)

Please excuse what I think is a dumb question. I was trying to stay away from a automatic reversing loop in the garden because of the electronics, so I though about a 22 or 30 degree CROSSOVER to solve the problem of a small-thin area i have for the dogbone shape loop. What I cant figure out is how the crossover works, it appears the inside rail becomes the outside rail after it passes thru the crossover? So it seems like a similar "problem" to the reversing loop which needs the polarity changed?? So are there any special electronics needed or its just a figure "8"?? I AM USING standard DC TRACK POWER!!
Thanks for your help?


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## kormsen (Oct 27, 2009)

no, if you make an "eight" with a crossing in the middle, your electrics stay just straight. you would need additional electronics just in the case, that you want to have two trains running at the same time. (to evade them crashing each other at the crossing) 
in a loop you bring back the track onto itself. then the right rail becomes the left. but not at an crossover. 

if you are relatively new to all this, you might want to take a look at this: http://kormsen.info/lgb-manual.pdf 
specially the chapter about taking control.


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## DKRickman (Mar 25, 2008)

Simple way to know if you have a problem: Follow both rails as far as you can. If one ever becomes the other (in other words, if you can start on one rail and end up on the other), then you have a potential short. In the case of the figure 8, the inside rail of one loop becomes the outside rail oft he other, but the two rails always remain separate. There's no way for a wheel to roll from one rail to the other. As it rolls along the 8, it goes from the inside to the outside and back, but there's always that other rail that it can never touch. By comparison, on a reverse loop, the wheel on one rail rolls along, goes through the loop, and finds itself on the opposite rail from where it started. NOW you have a short. 

Another method is to think about a locomotive. Can it reverse direction and come back the way it came on the same piece of track? If so, you have a problem. If not, you're fine.


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## Gary Armitstead (Jan 2, 2008)

Posted By DKRickman on 19 Nov 2012 08:28 AM 
Simple way to know if you have a problem: Follow both rails as far as you can. If one ever becomes the other (in other words, if you can start on one rail and end up on the other), then you have a potential short. In the case of the figure 8, the inside rail of one loop becomes the outside rail oft he other, but the two rails always remain separate. There's no way for a wheel to roll from one rail to the other. As it rolls along the 8, it goes from the inside to the outside and back, but there's always that other rail that it can never touch. By comparison, on a reverse loop, the wheel on one rail rolls along, goes through the loop, and finds itself on the opposite rail from where it started. NOW you have a short. 

Another method is to think about a locomotive. Can it reverse direction and come back the way it came on the same piece of track? If so, you have a problem. If not, you're fine. I remember the old model railroad books on wiring your railroad back in the fiftie's, where they made one rail NORTH and the other rail SOUTH. You just followed one rail around and if you had a N rail going into a S rail, you had a problem. Fifty plus years later, it is still in my mind! Battery...problem solved.


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## Paul Burch (Jan 2, 2008)

If you place a crossover on a dogbone it is the same as a reverse loop.


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## Greg Elmassian (Jan 3, 2008)

Just a bit of track terminology here: 

A "diamond" or "crossing" is two tracks intersecting at an angle, no switching is involved. 










A "crossover" is most often 2 switches that connect 2 parallel tracks. 











A "double crossover" is 4 switches and then you normally have a "diamond" in the center. 











What we are discussing here appears to be a diamond or crossing. 


(of course you can find these definitions completely messed up in lots of places, where a crossing is called a crossover, but you can see that the words themselves have meaning... crossing, you "cross" another track, you don't get on the other track, and crossover, you cross over to the other track... )

Greg


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## Totalwrecker (Feb 26, 2009)

Well since the old fig 8 didn't get a good feeling I suspect the problem is a reverse loop with in the dogbone. 
If you insist on track power you will need to isolate the cross over track (at both ends, both rails) and when your train is on that section, reverse the polarity of the dogbone loop and your train can proceed. Or buy a fancy electronic part that does the polarity change for you. DIY a DPDT center off switch (electrical switch). There are 6 poles on the wire side, incoming power is shaped like an X and attached to the 4 outer poles, track power comes from the 2 inner poles. 

I went to battery, it's easier for me to take the loco to the work bench rather than crawling around the layout. 

Happy Rails 

John


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## Greg Elmassian (Jan 3, 2008)

Or run DCC ha ha! 

I went to track power, it's easier for me to just put the trains on the track and run rather than fiddle with batteries and chargers. 

Touchè 

Greg


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## Totalwrecker (Feb 26, 2009)

Gee whiz Greg I woulda thunk you could have figured out batteries. 

The op wanted a plain DC solution, with wires on the ground kinda thing. You know, where stuff corrodes.... 
My comment got me off the ground, yours puts me back down there... I'll pass, thanks. 

Don't be so touchy! ha ha 

Happy Thanksgiving 

John


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## Greg Elmassian (Jan 3, 2008)

Sure I figured it out and it's not for me. 

But you are the guy who brought up batteries on a dc track power thread 

You can't blame me for your battery comment which was really not helpful, not needed and not on topic. 

Trying to lob it back to me is not going to work... and the decision is not as simple as just saying negative things about track power, I see you even added another comment about corrosion, though fee people have that problem, and you especially would never have it living in the arid desert. 

I'll stand by my retort. This stuff has no place on a beginners thread. 

Greg


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## Totalwrecker (Feb 26, 2009)

Au contraire, mon homme, 
After I told him how to wire for his situation... concrete help not an off hand comment on DCC. 

It helped me, there are pros and cons either way. 

It has every right on a beginners Forum thread and absolutely none on a track power Forum thread. 
Ignorance, you want to keep newcomers in your corner at any cost? 

I think it's more helpful to give newcomers all the facts and let them decide... I have 2 reverse loops and absolutely no wiring problems nor switches to throw automaically or manually. I sweep the dirt off and go. Recharge after a run and it's the same as yours, put it on the track and run. I park cars outside, not locos, so no matter the power source that job remains. Well almost the same I have way fewer options on control, but my trains get around fine for me. KISS works for me. 
When I ran track power I had many times on my knees trying to figure out what was wrong. All I know about corroding stuff in Aristo products came from you, so I thought that was a valid point... 

Lighten up and enjoy life, please. 

Happy Rails to All y'all. 

John


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## Greg Elmassian (Jan 3, 2008)

I will agree that helpful information to newcomers is good. 

Biased or one sided comments, i.e. the pros without the cons, or in this case, 2 cons on track power with no pro's, I maintain it is not helpful. 

I'm as light as can be by the way. Just expressing my opinion. 

Greg


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## Totalwrecker (Feb 26, 2009)

That's your job (the pros of DCC) I know not enuf to talk about it other than the inconvenience of track power for ME. 
I can only speak from experience. 
On a friendly board; I throw out what I know, you add your positive info and the OP makes up his own mind. 

I feel that your policing of the thread was way out of line, I used to ike you, then I tolerated, now I try to avoid you and beinng talked down to. 
I love the knowledge you share, that's wonderful. 
I can do without your Opinions, 'cause they seem as fair and balanced as Fox News.... 

What really irks me is you could have let my post slip by and we would have avoided all this brouhahahah 
but no, you had to let me know that my post wasn't up to your standards, thanks for nothing. 

John


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## Greg Elmassian (Jan 3, 2008)

Aside:
Sorry that you feel you have to keep "upping the ante" and make it personal and inducing politics as well. [/b]

*The OP put " I AM USING standard DC TRACK POWER!!" in his first post.*

*Why do you think he put it in caps?*

*Most likely to avoid a "battery guy" to tell him about the foibles of track power and the benefits of battery power.*

*But you insisted to put in not only one "dig" but two in 2 separate posts against track power.*
[/b]
*Yet you defend this as helpful? Courteous? Respectful of the OP?
*

*Yeah, it's all my fault and Fox News too.*

Anyway, back on topic: Gregg, If you wanted a crossing for some added interest, no sweat in the wiring, nothing to change, you are just making a long figure 8 and no electrical issues, the crossing will "carry" power through the "straight paths".

Now if you wanted to reverse direction you will effectively make a reversing loop. There are several products on the market which will automatically switch the polarity of the track when you "take" the reversing loop. Unfortunately in DC, probably the best choice off the shelf is the Massoth, which is close to $200.

It can also be done with contacts and relays in the switches themselves, and a bit cheaper I believe, using LGB components, and there's lots of people that can and will help you with the wiring diagrams.

Finally Todd Allen (I may have spelled his name wrong) can do basically anything with relays and has helped many a person. This is not really a complex circuit.

Greg


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