bagal richhotrain Oops, sorry about that. How about this? Rich Isn't there a risk of two trains in the reversing section at once with this arrangement? Bill
richhotrain Oops, sorry about that. How about this? Rich
Oops, sorry about that. How about this?
Rich
Isn't there a risk of two trains in the reversing section at once with this arrangement?
Bill
There is a risk. There is a risk in any reversing section, but the problem with this configuration is that two passing trains on the mainline tracks would cause issues as they enter and exit the reversing section even though they are not using the divergent routes on the crossovers. For that reason, I really prefer the 4-track configuration as opposed to the 3-track configuration. That way, no train would enter the reversing section unless it planned to use the divergent routes on the crossovers to reach the other mainline. In that case, I would consider the outer two tracks as the mainlines and those two inner tracks as the reversing section.
Alton Junction
Keep us posted on your progress. What is your timetable for laying track and wiring the layout?
The thing that intrigues me about the third track is the ability to keep trains moving even when two trains are traveling toward each other on the same track. For that reason, the longer you can make that third track, the better. Here is another thought. Add a fourth track on the right side. Oh yeah! With three operators, this just adds to the fun.
That looks great!
Yes! That is what I was thinking too! That way the entire gapped middle section of the centre and the right track become the reversing section.
Just curious is there a reason that you changed the wiring from red (positive) outside on the mainline? I know that the middle gapped section needs to be wired in phase but can I still keep my red outside/black inside convention for the rest of the mainline?
Well, then, we are back to wiring the reversing section in phase so you don't have to gap the centers of the crossovers. Now, you only need 5 feet up and down the mainlines.
Below the crossovers I have a clear 20-30 feet. Above it's a max of 5 feet.
It seems that you surely have at least 10 feet of track below the bottom crossover on the left side mainline, correct?
How many feet of track above the upper crossover on that left side track before you reach that turnout to the siding (Middlesex Mfg.)?
That original idea still anticipated 10 feet, not 5 feet.
Imagine a 10 foot long train crossing over from one mainline to the other mainline.
First, consider a northbound train on the right mainine crossing over to the left mainline. As it crosses the center of the upper crossover, it flips the AR-1. Now when it reaches those upper gaps on the left mainline, the trailing car has to clear the crossover gaps. So there needs to be a length of 10 feet.
Next, consider a southbound train on the right mainine crossing over to the left mainline. As it crosses the center of the lower crossover, it flips the AR-1. Now when it reaches those lower gaps on the left mainline, the trailing car has to clear the crossover gaps. So there needs to be a length of 10 feet there too.
No I do not have that space available. Would your original idea still work?
Yes, but recall that it has to be as long as the longest train. So, not only 10 feet in length on that middle track, but also 10 feet from the top gaps to the crossover gaps and 10 feet from the crossover gaps to the bottom gaps on the middle track. You need to account for the possibility of a train crossing from one mainline to the other mainline. Do you have enough space to do that?
OK. Is this where I put the 10 foot reversing section in this diagram?
Yes, my latest wiring diagram is different than that first one that I posted. In that first one, I was showing the wiring done in phase. In this current one, I stuck with your wiring protocol.
Is this different than what you indicated before? I thought that if I was adding the third passing mainline section that you didn't gap the turnouts and wired the middle section "in phase" to generate the reverse section.
No reason to be more confused than ever.
Go with #4, you and your sons will love it. The beauty of that arrangement is the simplicity of the wiring. Just wire it as you first drew it at the beginning of this thread. The diagram below shows the wiring and the gapping. The reversing section is easily identifiable, as it is that middle section of track.
I am back (sorry for the delay) and thanks for all of your excellent thoughts and comments! Hovever, I more confused than ever! Let me respond to some of your thoughts and questions in hope that I can achieve some clarity.
1. I am using Digitrax DCC so the AR1 shouldn't be an issue.
2. Each of the end loops have 24 inch radii so diameter should be approx. 150 inches or 12.5 feet which is more than enough to hold my max, train length of 10 cars and 2 engines.
3. I do indeed have a short at the crossovers involved as I have wired a continous loop as in the first diagram above, as the wiring follows the rails.
4. I was planning on using richhotrain's EXCELLENT idea of adding a additional left side mainline that could bypass the crossovers altogether, and the gaps in the middle of the two crossovers could be eliminated by wiring the middle track inside the gaps in phase with the right side mainline.
5. haven't figured out operations completely yet, however I have 2 young boys aged 5 and 8 and each are going to want to run a train so I guess that there will be 3 operators to start!
Wiring a continous loop poses a different issue, especially with crossovers involved. In the first diagram below, the OP's initial diagram on this thread, the wiring follows the rails. Then, the crossovers are gapped in the centers, and the one mainline is gapped to completely isolate the reversing section.
In the second diagram below, the two sides of the mainline are wired the same way, in phase, so there is no points of reverse polarity at the center of the crossovers. Then, the wiring of the end loops can be either way because the entry and exit points of the end loops are gapped to create two reversing loops.
It just seemed more logical to me on a shelf type layout to keep the bus wires in the same order. That also avoids wiring a simple passing siding backwards.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I guess that it is a matter of semantics, the use of the word "easier". It all comes down to how you think about how you wire your layout.
We haven't heard back from the OP in a few days. I wonder where he is in his thinking and what he may be planning to do regarding the location and installation of reversing section(s).
Easier? Wiring it like I do, regardless of the schematic location of the track, ie, say there are 5 tracks going across a section of the tables, the rail to the front of every track would be the white wire, and the rail towards the wall side would always be red (Red Rear). Crossovers would be the same phase throughout, and only the loops on the ends would need gaps and reversers.
Maybe different for an island layout, but for a shelf layout, this way just seemed more obvious to me when I built my first DCC layout.
mlehman richhotrain The actual operation of the layout will play an important role as well in terms of the number of operators and the number of trains running at one time. Since the end loops are at least 30 feet long, I can imagine a situation where one train is exiting the loop as another train is entering the loop, casuing the AR-1 to go nuts. 30 feet? Aw, but there's the rub. To use the end loops for reversing sections, they still only need a reversing section within them that is as long as the longest train. What's good about using them is they are not constrained by trackwork. Any section within each one that's long enough can be chosen. All the track leading up to and out of that section that's physically part of it need not be electrically included in the reversing section. That's a big reason why I favor using part of the loops, rather than the center section. If the reversing section length later needs adjusted, it's a matter of cutting a new pair of gaps and adjusting the feeders. There's no need to feel constrained by trackwork like turnouts, etc
richhotrain The actual operation of the layout will play an important role as well in terms of the number of operators and the number of trains running at one time. Since the end loops are at least 30 feet long, I can imagine a situation where one train is exiting the loop as another train is entering the loop, casuing the AR-1 to go nuts.
30 feet? Aw, but there's the rub. To use the end loops for reversing sections, they still only need a reversing section within them that is as long as the longest train. What's good about using them is they are not constrained by trackwork.
Any section within each one that's long enough can be chosen. All the track leading up to and out of that section that's physically part of it need not be electrically included in the reversing section. That's a big reason why I favor using part of the loops, rather than the center section. If the reversing section length later needs adjusted, it's a matter of cutting a new pair of gaps and adjusting the feeders. There's no need to feel constrained by trackwork like turnouts, etc
"ADJUSTING THE FEEDERS" - - - the operative words, and that is true throughout the rest of the layout.
I would find it easier to do as the OP has done, and that is to wire the layout as continuous loop, red feeder wires to outside rails and blue feeder wires to inside rails. Then, just cut the gaps between the connecting turnouts on the two crossovers and up and down the left side mainline, eight feet apart.
What could be easier?
richhotrainThe actual operation of the layout will play an important role as well in terms of the number of operators and the number of trains running at one time. Since the end loops are at least 30 feet long, I can imagine a situation where one train is exiting the loop as another train is entering the loop, casuing the AR-1 to go nuts.
Mike Lehman
Urbana, IL
bagal Did the OP say what DCC system he has? The AR1 doesn't work with some DCC systems. It is OK with NCE but doesn't work with the Bachmann Dynamis (not that one would want that system anyway), not sure about other systems. The Dynamis will trip out before the AR1 can reverse the polarity.
Did the OP say what DCC system he has? The AR1 doesn't work with some DCC systems. It is OK with NCE but doesn't work with the Bachmann Dynamis (not that one would want that system anyway), not sure about other systems. The Dynamis will trip out before the AR1 can reverse the polarity.
The OP did not mention the type of DCC system that he uses to power his layout. I have an NCE system with five AR-1 units on my layout, so I can vouch for the AR-1 with NCE. Obviously, the AR-1 will work with Digitrax systems as well.
I was not aware that the AR-1 will not work with certain DCC systems. From time to time, threads pop up on this forum comparing and debating various auto-reverse units. The PSX-AR is preferred by many, but I have no problems with the AR-1, and it is half the cost of the PSX-AR.
bagal Hi Rich I understand what you are saying now. If the OP has wired as a contious loop, yes the wiring would be out of phase. In any case the reversing section has to be completely isolated. I would use the loops because I think it allows longer trains but one would need a closer look at the layout dimensions to confirm.
Hi Rich
I understand what you are saying now. If the OP has wired as a contious loop, yes the wiring would be out of phase. In any case the reversing section has to be completely isolated. I would use the loops because I think it allows longer trains but one would need a closer look at the layout dimensions to confirm.
Bill, thanks for your comments on the reverse section and your reason for preferring the end loop as the reversing section.
I agree with you that the actual dimensions of the layout and the length of various sections of track including the end loops would help considerably. The OP did mention that the end loops are at least30 feet long.
The actual operation of the layout will play an important role as well in terms of the number of operators and the number of trains running at one time. Since the end loops are at least 30 feet long, I can imagine a situation where one train is exiting the loop as another train is entering the loop, casuing the AR-1 to go nuts.
rrinker I say use the loops because a) they are more then long enough and b) the are not close to the crossover - especially the top left one. Just the straight between the crossovers is too short for an entire train. A more common track arrangment for the dogbone with crossovers is that the crossovers are each near one of the loops - then it's probably easiest to make one of the straight sections the reverse section. --Randy
I say use the loops because a) they are more then long enough and b) the are not close to the crossover - especially the top left one. Just the straight between the crossovers is too short for an entire train. A more common track arrangment for the dogbone with crossovers is that the crossovers are each near one of the loops - then it's probably easiest to make one of the straight sections the reverse section.
Randy, while I agree that the crossover itself is obviously too short to accommodate the entire train, the proposed reversing section includes a length of track up and down the left side mainline, long enough to accommodate the longest train.
One complication with making both end loops into reversing sections is that all of the remaining track outside of the loops must be wired the same way, in phase. Of course, with care, this can be done, but that differs from the OP's initial track plan which is wired like a continuous loop. And, that is what causes the crossovers to have mismatched polarities where the turnouts connect together to form the crossovers.
bagal richhotrain but the problem remains that the crossovers each represent a point of reverse polarity that still has to be dealt with. This doesn't seem to be correct, or perhaps I don't quite undersatnd what you mean. The crossover doesn't create any reverse polarity in itself and no gaps are required. I agree that the crossover section could be the reversing section only requiring one auto reverser but if this was my layout I would be making the loops the reversing section. The cost of a second auto reverser is a small proportion of the total cost of this layout. Bill
richhotrain but the problem remains that the crossovers each represent a point of reverse polarity that still has to be dealt with.
but the problem remains that the crossovers each represent a point of reverse polarity that still has to be dealt with.
This doesn't seem to be correct, or perhaps I don't quite undersatnd what you mean. The crossover doesn't create any reverse polarity in itself and no gaps are required.
I agree that the crossover section could be the reversing section only requiring one auto reverser but if this was my layout I would be making the loops the reversing section.
The cost of a second auto reverser is a small proportion of the total cost of this layout.
In this case, the crossover is the point of reverse polarity because the connecting turnouts that form the crossover are not in phase electrically. That is because the track is folding back onto itself. The polarities of the rails don't match where the turnouts connect.
For the most part, crossovers do not present reverse polarity problems. On my layout, a double mainline, I have several crossovers connecting the mainlines and they remain in phase, no gaps, no reverse polarity. But, that is not the case on the OP's layout.
You mentioned that if this were your layout, you would make the two end loops the reversing sections, but you didn't say why. i would welcome an explanation of why the end loop(s) would be preferred to the crossover as the reversing section.