On my last layout we tried working with 2 reversing loops to create as much action as possible, the problem was that the loops were so big, the special modules that we hooked up couldn’t cover something of that maginitude, so there were still problems, although we did get them to work eventually, but it cost many hours of frustration.
How many on here have reversing loops on your layouts and I want to find out the general feeling about them on here, regarding their pros and cons.
On small layouts (6x10 in HO and smaller), I avoid them unless some sort of auto-reverser is set up. Unfortunately, if any spurs that need switching are attached to the reversing loop and/or the reversing loop is used in both directions, DC auto-reversing becomes quite complex. Bottom line - if you are using reversing loops on smaller layouts, use DCC.
A wye or a turntable doesn’t suffer from the same issues, because the locomotive stops while it is being reversed. This gives the operator the chance to manually align the polarity of the track. It’s also easier to set up DC auto-reversing with a wye or turntable (split ring wiring is an example of a turntable auto-reverser).
To be honest, reverse loops generally don’t look that good on a model layout unless you give them more than the minimum space. The reverse loops need some eye distraction from the toy-like atmosphere a minimum space reverse loop creates (yes, I know there are prototype reversing loops - but they are seldom used the same way in the model world). One of the more common “tricks” is to locate some industries or a town in the interior of the loop. Another common method is to hide the curved portion of the loop in a tunnel or have it go below grade.
my thoughts, your choices
Fred W
With a loop it’s a bit more difficult to create a schedule. But this loop has two tracks.
Here at another meeting:
Wolfgang
Reverse loops, the Mobius strips of model railroading. Operationally being able to turn the train around means you turn facing point turnouits into trailing point turnouts. It’s MUCH easier for your peddler freight to drop off/ pick up cars from sidings with trailing point turnouts. At a trailing point turnout you just back the train up the siding and uncouple the cars. Facing point turnouts have the locomotive going in first and there is no way to drop off cars and get the locomotive out of the siding. It’s trapped behind the cars. If you have a reverse loop, the peddler can service the trailing point sidings on the way “out”, turn himself around, and on the way “back” service the facing point sidings he skipped on the way out.
On the other hand, working the two reversing toggle switches, correctly, requires skill, so much skill that reverse loops on many layouts see little use.
The electrical problem is straight forward. Take one rail, the north rail for the sake of argument. Mentally bend the flex track around until it joins back to the stem track. You find that the north rail has looped around and joined the south rail. That’s a short circuit. It’s a short circuit for DCC too.
The traditional solution is to put electrical gaps in the reverse loop and power the loop track thru an auxiliary reversing toggle switch. As the train enters the loop you set loop polarity to match the main polarity. Once the train is fulling into the loop you reverse the polarity of the main line to leave the loop. If you don’t do it right, the train makes a sudden halt at one gap or the other when it encounters opposite polarity at the gap.
You can make life a little easier on your self with indicator lamps, one at each gap, wired across the gap. If the polarities match, the lamp sees no voltage and stays dark. If the polarity i
Hi!
My previous HO layout of 14 years had two reverse loops. One was in the lower level staging area and pretty much hidden, and the other was raised above the main level, taking up a lot of space.
On the plus side, being able to reverse whole trains was really interesting and made for more variety in operations. On the down side, being a DC layout, if I didn’t operate it for more than a week or so, I tended to have to relearn the controls when I again ran the trains. And, the upper level took up way too much valuable space, and overshadowed the engine terminal facilities within the loop.
My new layout, currently under construction, has no reverse loops. While I did convert to DCC, it was tempting, but again, it would just take up too much space that could be used for other stuff.
As an aside, the previous layout had lots of rockwork and tunnels (associated with the raised reverse loop), and their absence also adds to more space for structures and dual main running.
Of course, its all a matter of preference, and frankly I may miss having that facility when the layout is done. Soooo, we will see!
Mobilman44
I’ve yet to install one on the new layout and am contemplating weather I need/want it or not. For some I feel do to space constraints it’s a necessity. In any case if I do decide to install one I definitely will use an auto-reversing unit. I feel thats the sole purpose of technology is to make our lives easier so why not take advantage of it. I am sure more then one person back in the old dark ages of analog had wished for something like auto-reversing control if not how else would it have come to be.
I have a reverse loop, actually a diagonal crossover track in an oval. It has the advantage of having two start points. The bad news is that this arrangement ends up with a relatively short reversing section, and occasionally I get shorts because the train isn’t fully in the reverse section before the engine gets to the other end. I use DCC and an auto-reverser, and I find that works very well.
I’m starting an addition, which will have another reverse loop at the far end. It will be oriented for the other direction of travel, so I’ll be able to set up continuous roundy-round or loop-to-loop operations.
I have two reversing loops on my 4’X14" DCC HO layout as shown in this old picture. There is one PS/AR auto reverser from Ton’y Train Exchange for each loop. They have worked flawlessly but the length of a train is limited to what will fit between the two tracks being reversed.
Along with the two reversing loops there are two cross overs on the mains so I have all sorts of action possibilities. It keeps thing from getting dull. Using Peco curved turnouts facilitates installing spurs inside of the loops
Have fun !!
Bob
My Yuba River Sub is actually an entire gigantic double-reversing loop in the form of a somewhat convoluted Dog-Bone. I designed it with non-parallel double track, somewhat like the old SP Donner Pass line between Newcastle and Colfax, CA. The only place the double track is actually parallel is through Deer Creek Yard. I found that the wiring was pretty simple to do ((I’m DC), and actually only required one directional controller in the yard, where there are two crossover turnouts if I need to change from the eastbound to the westbound track, or vice versa. Not a problem. It also allows me continuous running when I want.
On my old layout, which was single track, I also had two reversing loops, and I didn’t find flipping the toggles to be a problem. I don’t know if it’s different with DCC, though.
Tom [:)]
David’s method will work, but there’s a much simpler solution for DC users - it may also work for DCC.
Simply use two switches: one to control the direction of all track on the layout, another to control only the isolated section of the reverse loop. One you’ve set the direction switch on your power pack, there’s no need to ever use it again. I use walk-round throttles of various types (all DC) that all have a direction switch on them. I then simply installed a dp/dt toggle switch on the layout facia near my turning wye (operates electrically the same as a turning loop), connecting wires from the power source to one set of contacts on the switch. I then added jumpers from those contacts to the opposite set, reversing their positions. After installing insulated rail joiners in both rails of both tracks leading to the wye’s turnout to the tail track, I ran wires from the switch’s centre contacts to the isolated rails. For a reverse loop, the rail insulators should be placed within the loop, preferrably immediately after the turnout leading into- and out of- the loop.
Before the train gets to the loop (or wye), set the loop’s direction switch to match that of the entry track. Once the locomotives are entir
I have 4 of them on the Seneca Lake Ontario and Western. One of them is a 3 track staging area, and another has a staging siding as well. When I was DC and the layout was much smaller the two reversing loops always had to be checked for polarity before each train went in and then the main track had to be reversed, and then… If there were two trains operating I had to make sure the polarity was right when the other train came to the loop, and then… Flip, flip, flip, opps, flip, flip…
I now use DCC, automatic reversing in the loop itself, never have to throw a polarity toggle for the main line. In other words I run my trains, not my track, and everything works without ever having a polarity problem. Ever!
If you have DCC it is a simple thing. With DC it is a bit more complicated (and I found frustrating) but still workable.
73
All of my needs for turning full-length trains end for end are handled by a single specially-wired section of track in the netherworld. It’s used by every locomotive powered train that leaves the visible world, a necessary evil that makes my operating scheme possible. Actually, it doesn’t have a separately-wired reverse switch. It DOES have auto-stop circuits, and movement through it is controlled by connecting it to the block ahead - one is the UP main, the other is a crossover to the DOWN main. The necessary contacts are on the switch machine.
As for reverse switches, each of my train controllers has two. One sets timetable direction (up or down) and the other determines which way the locomotive will travel (smokebox first, or tender first.) The direction switch only has to be set once for each train movement. Switching moves are controlled by the locomotive reverse switch.
Chuck (Modeling Central Japan in September, 1964)
My solution would not be satisfactory for most layout builders, but I like the reversing loop bridge running diagonally across the central operating pit of my layout. It is a 24" minimum radius at its tightest, generally 28", and gapped to allow a train about 7’ long to use it. A Digitrax PSX-AR reverses the polarity automatically…a wonderful device.
-Crandell
Any toy train system that uses two rails and gets its power through the track will have reversing loop issues. It is definitely not an HO issue. The new electronic auto switches especially for DCC have largely eliminated the old “run the track” issue. As for pro’s and con’s:
Pros:
Cons:
The solution on my Santa Fe was to not use any. The mainline is point to point and into staging. That is the top deck. The middle deck is a Santa Fe branch off the top deck and runs through the layout and down to a third deck where there are two more staging areas. At one time I had a staging track on the top deck set up to let me run through trains in a loop during open houses, but that finally got pulled.
Bob
This is one of the classic, and best, ways to use reverse loops and by far one of the best ways to wire them. I use this same idea in all reverse loops on my layout as well. Like Chuck, all my reverse loops are “off stage” trackage to prepare for the next run, session, etc.
And this type of wiring is easy to understand and operate even in DC, and will work with DCC as well.
This idea was recommended and promoted by Paul Mallory and others back in the “dark ages” of our hobby. Ideas that still work well dispite their “age”.
Sheldon
The method which I outlined previously doesn’t require stopping the train, either. [swg] On my first layout, a 4’x8’, there were two reverse loops.
Wayne
Selector, I really like your layout plan. What are the dimensions of the table and how big is the room if you don’t mind me asking…
Oh and did you lay your cork road bed on plywood? I see some blue foam used on top of plywood in some places, how did you make the transition from foam to plywood? Or do the tracks and cork roadbed lay on foam as well?
I also forgot to ask, do your large non-articulated steam engines have problems with #6 switches or do you use only #8 turnouts for the T1 and J1?
And whats the largest radius on your layout?
Hi. Layout is in one corner of the basement, measures 9’ along the close and back walls as you see it, and the length, right and left, is 13’ 9". It is a folded loop design strictly for rail fanning, although the yard offers switching of a sort, and the engine servicing is obvious. Also high along the far wall, a switch back to a mine in a tunnel in the far mountain, highest up.
I use Peco Streamline Insulfrog Code 83 $6 turnouts exclusively in the yard, and one is part of the switchback to the mine. All of my engines are perfectly happy with #6’s, and I would bet they would be fine with #5’s. Same with my Walthers heavyweight passenger cars.
The crossover central bridge is the only construction of that nature, and that was because I had materials left over from a previous layout and wanted the bridge to be light. It is hinged at the right, where it meets the bench, and is held up by brass bolt latches at the left. Those latches also transmit power to the rails on the bridge via hidden feeders.
I only have roadbed, and it is cork, inside the tunnel to the low left, running behind the length of the yard and depot. All the rest is spline roadbed with flex laid directly on the spline tops.
The radius at the near (out of camera view) and far walls comprise the largest curves, and they are about 46". Other curves are limited by the largest curved turnouts I could find, which I hacked up in order to ‘straighten’ them a wee bit to eke out another 2-3" of radius. They are Walthers/Shinohara #7.5’s with are tighter than advertised on the inner diverging route by about 3". I have one curved W/S #8 that seems to be closer to its advertised radii, but many items clunk through the frog…engines and cars. Unable to determine why so far. It looks clean and well made.
If you have other questions, please feel free
You really don’t want to know what I think about them. What is important is you want them so you can reverse train direction as trains run around the layout.
If DC, one simultaneously reverses the electrical polarity on the reverse loop and the throttle’s train direction. You may or may not want to do this while the train is running. If DCC, one employs an electrical gadget (as mentioned earlier by someone else) to align polarity automatically.
Mark