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Reverse Loop Question

georgebriscoe10 All Messages By This Member #14271 Greetings All. I have been a member of this group for many years and have found the information provided very helpful. I think I have made some contributions in the past. I now need a little help with a reverse loop I have created on my new layout. I have wired simple reverse loops previously but only in DC. My situation. I have a length of track leading into a revere loop but it doesn't join the incoming track directly when it exits the loop. It exits onto a track parallel to the incoming track. This is is fine but just outside of the loop I have a crossover that joins the inbound and outbound tracks. Not surprisingly I get a short if I try to go through this crossover. There are gaps in the crossover track but they are staggered. They are the gaps that isolate the frog of each switch. My question/s are do I use an auto reverser on the loop and, if so, do the gaps at the crossover need to be adjacent? Will this work? Or is there an alternate solution? Can I connect the auto reverser to the 2 parallel tracks leading into the reverse loop. I have seen this solution used to simplify certain situations. I am hoping somebody can provide a solution so that I don't have to go through a lot of experimentation. For you info, I use a Digitax command station with input via DCC Specialities PSX CB's. I have a couple of DCC Specialities Frog/AR's for the reverse loop. Thanks in advance for any suggestions you can provide...........................George.
Tim All Messages By This Member #14272 George; The simplest solution is to make the crossover the end of the reversing section. In this case you would gap both tracks on the crossover track and at the frog end of both turnouts. Just don't try to run two trains across the gaps on both tracks at the same time. Tim Rumph Lancaster, SC
[email protected] All Messages By This Member #14273 George, Tim's answer is correct, but without a picture, it seems a little confusing. I would answer your question this way - Make the loop the reversing track, and double-gap the rails at each end of the loop before the crossover. In addition to making sure you don't run two trains across both gaps at the same time, you also want to make sure the loop is long enough to hold any train that draws power along the length of the train; for example, a passenger train with coaches that are all lit (which wil lresult in the same effect as 2 trains crossing the gaps at the same time). David
Jerry Michels All Messages By This Member #14274 George, You already have two good responses, but I wanted to mention that I think we have the same situation on our layout. We use a BXPA1 to control the reverse loop, and it works well. I agree with the previous posters. Jerry Michels Amarillo Railroad Museum
georgebriscoe10 All Messages By This Member #14275 开云体育 Thanks to all who responded to my question. It basically confirmed what I had thought. I do have a follow up question. It is to do with which option is better. Gap before the exit crossover or Gap between the crossover. To explain. My situation is that as I enter the loop on the left hand track, I cross the trailing point switch of the crossover. As I exit the loop I cross the other trailing point switch of the crossover. Following this switch I have about 2 metres of straight track before it meets another crossover. My thoughts are that if I gap between the 2 switches of the crossover it would allow me to extend the length of the reverse loop until that next crossover further down the line. I could gap the rails before that subsequent crossover. I think this would work and would allow me to extend the length of the reversing section considerably, which is desirable. My question regards the gaps between the said crossover. Must they be adjacent? I suspect they must but those that have had more experience may be able to confirm this so I don't go off cutting unnecessary gaps.? As I mentioned in my original post, there are gaps between the crossover switches but they are not adjacent. They are simply the gaps that isolate the Frog in each switch. They are about 40mm or so apart. From what I have read about reverse loops, the gaps need to be adjacent. It makes sense. Thanks for any information you can provide...........George.? ??
[email protected] All Messages By This Member #14276 Hi Goerge, I must apologize for my previous answer as it is not totally correct. Something didn't seem right in my mind, so I drew the picture. It really helps if you draw the picture. What you need to do is install 3 sets of double gaps. (When I say "double gaps" I assume that is the same as what you are calling "adjacent gaps" - a gap in each rail of the track at the same spot.)? The problem is that the conflict in polarity occurs at the crossover nearest the loop, so to solve that you have to include half of that crossover inside the reversing section.?So install 3 sets of double gaps: one pair of gaps at the end of one side of the loop before the crossover nearest the loop (as described previously), one set between the crossover turnouts, and then one on the other parallel track beyond that same crossover. Your idea that you can move the gaps further toward the next crossover is also correct.?And yes, your thought about the gaps being adjacent within the crossover is correct. The gaps for the frogs simply isolate the frog where the opposite-polarity rails cross each other.? Again, sorry for the confusion in my responses.? David
Don Weigt All Messages By This Member #14277 George, I think what you are saying is correct. You can extend either end of the reversing loop through one turnout in your nearest crossover.? What isn't allowed is to do that with both turnouts of that crossover. Doing that would cause shorts every time a loco or lighted car's connected, powered wheels bridged the gaps between the two turnouts of the crossover. Also, any trains taking the crossover would have to be clear of the reversing section on the other side. You probably would find that still limits you to shorter trains than you want. Don W -- Don Weigt Connecticut
georgebriscoe10 All Messages By This Member #14282 开云体育 No need for apologies David. It can be difficult picturing a situation without a diagram.? Thanks for confirming what I had suspected. The parallel tracks exiting the loop does complicate the situation a little. After some experimentation I also realised I made an error in how I wired the parallel tracks exiting the reverse loop. My initial thought was maintain the polarity of the track into an out of the loop. This means the two parallel tracks had the opposite polarity. This worked okay until I installed the crossover. This caused a conflict which took some time to work through. I think the correct approach is to consider the parallel tracks as one, same polarity, and let the auto reverser do it's job. I will find out if this is true in the next few days. It's been a long time since my first, and only, reverse loop. In DC and a simple DPDT switch. But I am enjoying the challenge................George.??
Tim All Messages By This Member #14283 If you want to extend the reversing section onto the double track portion I would recommend using relays driven by switch machine contacts rather than an automatic reverer. I'm not going to claim that would be simple, but it's much more practical. Tim Rumph Lancaster, SC
georgebriscoe10 All Messages By This Member #14288 开云体育 Thanks Don. Understood......George.
georgebriscoe10 All Messages By This Member #14292 开云体育 Dear All, For those that responded and are interested, I solved the scenario. All works well. It did take some experimentation with wiring connections but after a "process of elimination", I solved the problem.? As for looking at files before posing a question, I thought this is what the forum was for. If nobody replies to my question I have to go it alone. Thankfully, some people did reply and confirmed what I had thought. The situation was a little different from normal. If it had been a single track entering and exiting a reverse loop I would not have needed any help. The fact that the reverse loop entered and exited on different, parallel tracks, with a crossover, was very different. In the end, my initial thoughts were confirmed by some responders and saved me cutting any unnecessary gaps. It has been a very interesting and enjoyable journey. That I solved the issue, with some welcome help, is most satisfying. Now onto the rest of the layout and one other reversing loop. This one should be a little easier. Thanks again...............George.? ??

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