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HO layout (DDC) Reverse loop help

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Posted by mlehman on Sunday, May 26, 2013 9:44 PM

Exactly. That's why I interjected some detail about how long the reversing sections needed to be when describing my approach. The various selections in how to do this mean there's options no matter what the intent and real estate situation happen to be.

Mike Lehman

Urbana, IL

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Posted by richhotrain on Monday, May 27, 2013 6:04 AM

It also depends upon the routes and the reason for those routes.

To illustrate this point, I numbered the six turnouts in this portion of the OP's layout.

I count at least 12 possible routes through the circle configuration, some of which make more sense than others.

Until we hear back from the OP, my guess is that the circle is to permit trains to turn back on their routes without proceeding from one side of the layout to the other.  For example, trains entering the circle from the north (top) can use the circle to return north without proceeding any further east (bottom).  The route would be 123561.  In te same manner, trains trains entering the circle from the east (bottom) can use the circle to return east without proceeding any further east (bottom).  The route would be 432654.

Depending upon the size and purpose of the circle, it could be used to divert trains into a passenger station or spur line and then continue on its route.  Examples of this would be routes such as 12356234 or 43265321.

Simpler routes would include 1234 and 4321.

To avoid head on collisions, trains traveling in both directions could simultaneously proceed on routes 1234 and 4561.

So, a lot depends on the size of the layout and this particular section of track, the desired length of the reversing section, and the size and purpose of the circle.  If the metal wheeled locos are pulling plastic wheeled rolling stock, the requirements will be different than if the train is pulling metal wheeled rolling stock or lighted rolling stock.  Particular attention needs to be paid to the wiring of this section of track and the location of the rail gaps.  The number of trains using this section of the layout will also be critical because of the necessity to avoid having two trains entering/exiting the reversing section simultaneously.

Hopefully, we will hear back from the OP regarding all of these issues.

Rich

 

Alton Junction

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Posted by mlehman on Monday, May 27, 2013 8:55 AM

Rich,

That's a great problem definition for setting up the macros I mentioned earlier. That way you can then choose routes with MACRO+single button push, at least with NCE.

I'd guess that in practice that only some of these routes would be used, like you say, it depends on what the rest of the layout is like and what ops are planned to pass through it. That would also contribute to how to handle the scenery.

One thing this config would be good for is in a corner for access to staging. If staging yard leads were placed between 1 + 2 and 3 + 4 extending AWAY from the corner defined between 2 + 3, it would be easy to turn the train from either direction and back into stub-ended staging yard tracks. If there was LOTS of room, then those staging tracks could be double-ended and rejoin the main to head back without the need for backing up.

I'd guess the OP doesn't have something quite this space-hungry in mind, but for someone who needs to deal with staging on a large around the room layout might find it helpful. Obviously, the basic diagram can be translated in practice so that it's more photogenic. I can see a set of junctions, with the track between 5 and 6 acting as a sneak around, but with a low key disguise like tail track for an engine facility. Such a service facility takes a lot of space. I could see it serving both ends of the layout, even if each end otherwise had separate yards.

Mike Lehman

Urbana, IL

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Posted by richhotrain on Monday, May 27, 2013 9:26 AM

Mike, great reply chock full of good ideas and suggestions.

I particularly like your suggestion about the ability to choose routes with MACRO+single button push, at least with NCE. 

Now, we just have to wait for the OP to respond and tell us more about his layout and his objectives.

Rich

Alton Junction

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Posted by Vieredy on Monday, May 27, 2013 11:38 AM

Guys,

I was out of touch due to business and now I'm back catching up.  Here are some bits to chew on;

Layout is HO scale with Digitrax DCS100 + 1 DB150 as booster.  I'm finishing up on the lower level of a eventual 3 deck layout.    Loop is 28" radius,  the loop runs inside a helix,   I plan on using Digitrax DS64's for the switches, one AR1 for reverse loop,  and my main purpose of the loop was for reverse direction, while also using the configuration of the loop for passing thru trains.

sorry for the delay

Ed

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Posted by richhotrain on Monday, May 27, 2013 12:17 PM

Vieredy

my main purpose of the loop was for reverse direction, while also using the configuration of the loop for passing thru trains.

Ed, since the loop is primarily for reversing direction, while also using the configuration of the loop for passing thru trains, the, using my turnout numbering scheme, I assume that the primary routes are 123561 and 432654 for reversing direction and 1234 and 4321 for passing thru trains.

That being the case, gapping the turnout rails on 2,3,5 and 6 to isolate the loop as a reversing section seems to make the most sense since opposing trains would never enter the loop at the same time. Using a Digitrax AR-1 for this purpose would work just fine. I have included that track diagram here for easy reference.

Rich

Alton Junction

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Posted by Missouri Pacific BNSF on Thursday, October 17, 2013 9:40 AM

In the first reverse loop Diagram, where would I put an auto reverse module?  I assume part anywhere in the reverse section and the other part anywhere outside that section?  Does it or will it only take one auto reverse module?

 

Thanks

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Posted by Missouri Pacific BNSF on Thursday, October 17, 2013 10:19 AM

I now realize what is being said about train length, etc...  So in the post two post above this one, if I am using a DCC auto Reverse Module, I would insulate all turnouts and wye's outside the "circle" leaving the "circle" isolated; from there I would wire the auto reverse module ANYWHERE outside the "circle" on one lead and INSIDE the "circle" on the other lead correct?  Will one ARM cover everything for me then; both directions heading out of any turnout?

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Posted by richhotrain on Thursday, October 17, 2013 11:04 AM

MP BNSF,

It only requires one ARM.

Once you isolate the circle, the circle  becomes the reversing section.

You wire the input side of the ARM to your bus wires, and the output side of the ARM connects to any feeder wires inside the circle.

Any feeder wires leading to track outside of the reversing section ( the isolated circle) must be wired to the bus wires and should  not come into contact with either side of the ARM.

Rich

Alton Junction

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Posted by Missouri Pacific BNSF on Thursday, October 17, 2013 11:15 AM

Can I use the ARM as the only source of power (no other feeders) inside the reversing loop?  I am going to make the loop with a radius of 30 inches.

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Posted by richhotrain on Thursday, October 17, 2013 11:22 AM

Missouri Pacific BNSF

Can I use the ARM as the only source of power (no other feeders) inside the reversing loop?  I am going to make the loop with a radius of 30 inches.

Sure, you would connect two feeder wires from the input side of the ARM to the bus wires and two feeder wires from the output side of the ARM to the track inside the circle.

If you do that, just be sure that the one set of feeder wires inside the circle is sufficient to provide power throughout the circle.  Since four turnouts are part of the circle, connectivity could be a problem with only one set of feeder wires.

Rich

Alton Junction

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Posted by Missouri Pacific BNSF on Thursday, October 17, 2013 11:39 AM

If I spilt to have more feeder wires inside the reverse loop, I just do that at the ARM output wires correct?  Thanks, this has been a huge help!

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Posted by richhotrain on Thursday, October 17, 2013 11:58 AM

Missouri Pacific BNSF

If I spilt to have more feeder wires inside the reverse loop, I just do that at the ARM output wires correct?  Thanks, this has been a huge help!

What I do is two connect one pair of feeder wires to the two terminals on the output side of the ARM, then join all of the feeders from the reversing section together onto the other ends of those two feeder wires.

Rich

Alton Junction

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