loopy reversing loops ???

[chateauricher]

I have a problem. I'm planning my first layout in a small room. Its an around-the-walls 2-deck design. Since watching trains going in the same direction all the time will get boring, I will need reversing loops (2 per deck, 4 in all). However, to save space (its a really small room), I'd like to combine the reversing loops and have just one reversing loop (per deck) accessible from either direction.

[%-)]Does anyone have any idea how to do this with a minimum number of turn-outs (I've calcuated at least 6 are needed) ? Also, how would this be wired (I'm planning on DCC) ?

[%-)]Are there other options I'm not aware of ? [banghead]

Any help would be greatly appreciated.

[rrinker]

With DCC it's EASY - and automatic! You need an auto-reverser like MDC's, Digitrax's, or Tony's PS-REV. The loop itself needs gaps in both rails and each end. Loop power is fed from the auto-reverse unit, and the auto reverse is fed from either the main bus or with a direct run back to the booster, the direct run NOT being necessary, just connect to the nearsest source of power. When the train bridges the gaps as it goes around the loop, the auto-reverse will flip the polarity to match as needed and the train will continue on.
Best to get a separate auto-reverser for each loop than attempt to run two loops on one - if there is only one reverser and two trains are running, one in each loop, one reverse can't change polarity on both of them and you'll end up with a short and everything will stop.

--Randy

[jkeaton]

Six switches per loop would seem to be the minimum - unless you're willing to use double slip switches, then you need two of those and two regular switches per loop.

Do you need the continuous running option? One choice other than reversing loops would be to operate the layout as a point to point with terminal yards - but share one terminal yard, rather than two. Train 1 would leave one end of the terminal yard, called yard A, traverse the towns on the layout, then arrive at the other end of the terminal yard, now called yard B. The train is broken up, reclassified, and re-assembled, then it may be dispatched again from yard A as train 1 - or dispatched as train 2 from yard B.

Jim

[cwclark]

if at all you can just dogbone it ,you are going to save yourself a lot of trouble...with reversing loops, you're going to have to throw a switch every time the train enters the reversing block section if you don't have an auto reversing unit...trying to keep up with 4 at one time is going to drive you crazy...Chuck

[chateauricher]

jkeaton :

how would it work with double-slip switches? what would the layout look like? [?]

6 switches with motors will cost about $ 250+ per loop. [wow] I am hoping to reduce that cost. [sigh]

[jkeaton]

I'm not sure how to post a drawing here - but if you shared a circle of track as the "loop" for both of the reversing loops you need, then you'd need one double slip switch on each side of the loop. Let me try to walk you through it as if you were on a train approaching the loop. First, you'd come to a regular switch, and proceed left or right - let's choose right. Then, part of the circle of track that is the reversing loop would appear - between the two diverging tracks - and you'd come to a double slip switch. You'd enter the double slip from the right side, and have it set up so you exit from the left. Then you'd curve around half of the loop track to the second double slip switch. Here, you'd be entering from the left, and set up the switch so you depart from the right. Now you're off the loop, on straight track, heading back towards the regular switch where you started. You transit the regular switch and you're back on your mainline, reversed.

Jim

[mcouvillion]

I designed a railroad quite a few years back that was double main but had essentially a circle between the two mains, forming reverse loops from either direction. It only needed 4 switches. You could either "pass through" on one side, skirting the outside of the circle, or "loop around" to the other main going in the opposite direction. And you could do it from either direction! This was several years before DCC and it used snap track. I never got it to work because I did not like how the track plan worked out in other areas of the layout. It would have been a significant challenge to wire conventionally. Now, with DCC and the auto-reversers, it would be a piece of cake. I think the two sections of the circle between the two mains would each need a reverser, and you would have to figure out how to control the turnouts (routing?) for straight-through or reversing from any route going in, but once it was figured out for one route, it would be cookie-cutter for the rest. You could hide the whole thing or part of it in a mountain and really play with your operator's mind!

Since it would be a circle, you would not have to come into the loop at 180 degrees (straight), but could be 90 degrees or possible less from the opposite directions, allowing the circle to fit in a corner, kind of like a helix.

I'd like to see a sketch, or better description, of one that requires six turnouts. I'm sorry, but I can't imagine why you would need more than four.

Mark C.

[chateauricher]

mcouvillion:

My plans call for a single track main.

If I understand your description : a train on track A would be reversing direction; but onto track B. I want mine to reverse direction back onto the same track.

If I can figure out how to post a photo, I'll put a diagram here. If I can't post a pic, I'll email one to you.

[mcouvillion]

chateauricher,

OK, Got it! You are right, it needs 6 turnouts. My first pass guess is that you would need 4 auto-reversers for all the potential variations you could run into. I've got it sketched in front of me right now, really interesting and versatile. Not prototypical by any means, but it offers a bunch of operational options. It resembles trolley tracks going aroung a circle / fountain in the middle of a street intersection. Wow, I wonder why I never thought of that before!!!

Mark C.

[Anonymous]

I'm in favor of Mark C's idea. If space allows, build a double track main and swing them away from each other at one point so they're four feet apart. That way, you can insert a circle of 24 inch radius track, using four switches to connect to the main tracks. Kinda toy train like, in fact a lot, but very cool. No real reverse loops unless you absolutely have to have cross overs, which you don't. I guess pure railroaders will think I am thinking like a ten year old with a 1950's Lionel toy setup! It is certainly not prototypical, but I think it's a neat way to change train directions and avoid boredom, and you can hide most of the loop area in a mountain to keep first time viewers guessing which tunnel portal to watch to see the train reappear.

[chateauricher]

mcouvillion :
I realise its not exactly prototypical; but, then again, I'm not doing a layout based on any real rail network. I'm basically trying to get the most interesting layout I can in the space available. The room I have available is only about 6'-7" by 8'-2". [:(] My challenges include : dodging around a small closet in one corner; a window that I need to be able to access; keeping a walk-through available by using a 4-level swing-away bridge [wow] (due to arthritis, a duck-under is not an option); and a ceiling light fixture in the oddest location [%-)] .

geoeisele :
IF I had the space, I would do what Mark C suggests. [:(] Putting a 48" diameter reversing loop is just out of the question -- my entire layout would then consist of 2 reversing loops linked by a no-lix.

[Tom Bryant_MR]

On reversing controllers - has anyone used the ARSC from Loy's Toys at http://www.loystoys.com/. It uses a "portal" or sensing section at each end of the reversing loop.

[Jetrock]

chateauricher: Assuming you're using HO, your reversing loops will have to be *at least* 36" in diameter, and probably bigger. Have you considered other options for turning locomotives, like a turntable at each end, or a wye? A turntable can turn the locomotive around to reverse direction, and a wye can do the same job in a different way--and they work in both directions.

I notice you mention the layout is bi-level: will trains go from one level to the other, or are they effectively separate layouts?

Also, one money-saving piece of advice: For a layout that small, you really don't need automatic turnout control. A shelf layout's switches will all be within easy reach, you can save yourself a lot of cash by using manual turnout control for any switch that isn't hidden under scenery (and those should be kept to a bare minimum.)

[chateauricher]

jetrock,

No, I'm doing N-scale passenger trains on track with 15" radius curves. Turn-tables and wyes are great for reversing directions of the locomotives; but not so great for reversing the rest of the train. Mind you, some trains can go in either direction; but some consists are built in a specific order; and those observation bud cars (with the rounded ends) really can only go at the end of the train. So, to be prototypical, I need to be able to turn the entire train around

It is a 2-level layout with a no-lix linking them, so they are connected.

Manual turn-out controls are one option; but I'm a bit lazy [:I] and I'd rather sit back and push a few buttons than keep standing up to reach the turn-out controls (particularly on the upper deck).

Thanks, though. I appreciate everyone's suggestions so far.

[Anonymous]

Just and idea, how about just one reversing loop per level, putting one above the other. You could run in one direction on one level, change direction, run the other direction, change levels, run one direction on the other level, change direction, run back the other way, back to the other level and so on. I know this would give somewhat fewer options, but it might accomplish basically what you want without all the extra difficulty. Again, it's just another idea that I haven't yet seen posted.
-Joe

[chateauricher]

tom bryant_MR,

I can't find the ARSC reversing controller on loystoys.com that you are talking about. [%-)] Are you sure your information is correct?

[Tom Bryant_MR]

Sorry, Here's the direct link ... http://www.loystoys.com/loystoys/arsc.html. The ARSC stands for Automatic Reverse Section Controller. From the doc, it appears they have created something similar to Digitrax PM42. Claim is that this will handle seemlessly trains with power cars and trains entering and exiting the reverse loop at the same time - length of reverse loop is not relevant.

[chateauricher]

tom,

Thanks for getting the correct link. It does seem to be a very interesting device that might help solve a lot of headaches.

[Anonymous]

In Europe and Japan where living space is at a premium, micro layouts (typically 18" wide x 2' long) are popular. Check out this web site just to give you some idea in space saving. http://carendt.com/microplans/index.html
I don't know what era or road you model, but a point to point with a turntable (for steam era operations) or a run around track for the engine at each end (or combo of both) would be prototypical and save space. Some, if not most, railroads do not physically turn locomotives (especially diesels or steam engines on logging roads, short lines) and ran them in reverse. That would give you more hands on operation rather than watching the train go back and forth.

[jkeaton]

Thanks for posting the Micro Layouts site, Gary - while my a-building layout is bigger than that, I now have several good ideas for townsites, waterfront scenes, and terminal station yards.

Jim