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Common Rail on a Point-to-Point Track Plan?

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  • Member since
    January, 2008
  • From: Tampa, Florida
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Common Rail on a Point-to-Point Track Plan?
Posted by cedarwoodron on Friday, December 29, 2017 7:22 AM

I hate to ask what may be simplistic questions, but all my available info- Atlas Wiring Book, various websites dealing with wiring for DC- all reference common rail block wiring for closed loop track plans. My switching layout (in progress) is a series of right to left tracks with interconnecting switches. If the "top" of the plan is considered north and the bottom is "south", is the common rail of all track either one or the other?

This is in reference to a DC plan with 7 blocks.

And, not to belabor the point but, should I use a common rail approach with only an insulating plastic rail joiner on the other rail for each block or use two insulators for each block (thereby eliminating the common rail issue)?

Advice received now will make my wiring task more efficient later.

Thanks for any feedback.

Cedarwoodron

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Posted by mbinsewi on Friday, December 29, 2017 7:46 AM

You can have a stretch of track that goes from here to downtown, it doesn't matter.  Any track that comes off your main track must have the same common rail as whatever rail you used on the main.  If you tried to switch sides on any of your other tracks, you would be reversing the polarity.

If you gapped both rails, you could easily switch over to DCC if you ever wanted to.

I tried to respond to this earlier, but got an error message, saying this post didn't excist.  You must have been editing yours when I went to submit the the first time. Laugh

Mike.

  • Member since
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  • From: Chi-Town
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Posted by zstripe on Friday, December 29, 2017 8:13 AM

I would highly recommend not using common rail wiring. Go with two rail insulated wiring. You cannot use Atlas components then.....but a DPDT Center off toggle is cheaper than Atlas components. I say dpdt center off simply because...should You ever want to have 2-cab control (two operators) the toggles will already be there. Also if You want to switch to DCC later, it will be easier and You can turn off any block to park an engine or two or three when You want to. So when You power up with DCC You won't have all Your engines powering up also without having to mess with the DCC controller to turn them off or mess with CV's.

Your Call......

Frank

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  • From: Reading, PA
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Posted by rrinker on Friday, December 29, 2017 10:53 AM

 If you fake it you can still use the Atlas controls - gap both rails, run feeders to both sides. The commoin rail side, all the feeders tie together at a common point. The other side, they go to the Atlas control box. If you are only running one DC cab - use the Connector instead of Selector, they are DPST switches so they switch power off to both rails. Gap both rails, run 2 wires back from each block to the Connector. That's how I built ALL my layouts back in the day, and I learned by tracing what my Dad did on the hiliday layout we put up each year. I guess he didn't like common rail either.

                                       --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
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  • From: Tampa, Florida
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Posted by cedarwoodron on Friday, December 29, 2017 11:31 AM

Okay, let's say I elect to go the common rail route- I am heavily invested in a 20+ collection of steam and diesel DC units and have no present (or forseeable) wish to spend $$ on DCC hardware and circuit boards to convert (spent a lot of time refurbishing the swap meet purchases and the others were bought new); I'd rather spend on structures and scenic work (roadbed down and track push-pinned ready to secure).

I have a Tech 4 Dual cab power supply and have a diagram from online sources of a block wiring scheme that connects the cab DC terminals to an Atlas Controller, which then connects to 2 Selectors that power the 7 blocks I have determined. I see where the common "C" terminal on the Controller goes to the common rail and where the Selector terminals each connect to the 7 insulated/gapped rails of each block.

If I want to drop feeders from various points on the common rail side (north on my plan), do the Selector wires which run to each block on the insulated side(south rails) perform the function of feeder wires as well? If so, then I do not need another set of feeder wires, correct?

Again, sorry for the long-winded posts but I'm retired recently and can now devote more time to the hobby.

Cedarwoodron

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Friday, December 29, 2017 1:58 PM

 It depends on how long the 'block' is. If there's say 20 feet of track in one 'block' then I would absolutel drop more than just one feeder to the insulated rail, tie them all together, and run a wire pack to the Selector. And absolutely more than one feeder on the common side as well. There's no hard and fast rule, but every rail joiner is a potential weak point in conducting electricity to the next track section. With my (insulated frog) Atlas turnouts, I put feeders on all three legs - 3 for the 'north rail' and 3 for the 'south rail'. Common rail wiring or not, this made all of my turnouts bulletproof. I never had any power issues even with smaller locos going at slow speed. Conceptually it's just a whole lot of wires all connected in parallel, even if it seems like a mass of wire. Rather than string this all back to the control point, you run ONE wire for each rail to the control point, and then out under the layout drop as many feeders as needed and attach them to that one main wire. Rail joiners at best are unreliable over the long term - using fresh ones, they may start out just fine, nice and tight against the rail, no power issues. But paint the rails and get paint around them (and not painting the joiners isn't much of an option - they stick out like a sore thumb), or just run the layout for a few months and the weight of trains runnign back and forth loosens up the joiner - suddenly locos stall for no apparant reason when they previously ran fine. And unless your entire structure is built of materials that do not expand or contract within the expected environment of the layout room, it's not practical to solder EVERY rail joint - unless you carefully control temperature and humidity to prevent expansion and contraction. Soldering SOME works well, a soldered joint can be considered the same as having a feeder on either side, so you can solder some track together and have a single feeder there, then leave a joint unsoldered, and add another feeder on the next group of soldered track.

 Do it right the first time and you won't have to do it again after ballast and scenery are in place.

                                    --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    January, 2008
  • From: Tampa, Florida
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Posted by cedarwoodron on Thursday, January 04, 2018 9:39 AM

I see where some wiring advice sources (not forum contributors, but general info in books and online generic articles) speak to using those wired track connectors at various points along the trackage to add better electrical connectivity to a layout. On the other hand it is mentioned by some that track connectors are a weak point as they eventually may loosen (with operation of trains over them) and cause connectivity problems. If I use those wired connectors, should I solder them in place?

Alternatively, if I elect to wire feeders with regular wire soldered connections, one article mentioned doing so on the INSIDE of the track rather than along the outside, for better visual effect. Is that a better method?

Cedarwoodron

  • Member since
    May, 2010
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Posted by mbinsewi on Thursday, January 04, 2018 11:02 AM

cedarwoodron
On the other hand it is mentioned by some that track connectors are a weak point as they eventually may loosen (with operation of trains over them) and cause connectivity problems. If I use those wired connectors, should I solder them in place?

They can become a problem, even though your not taking the track apart and putting it back together again, they can fill with paint, dirt, etc, and loosen over time.

You can solder them. My layout is a continuous running mainline, all joints soldered, and located in a basement, where temps range from the 70's to the low 60's, and I haven't had any problems with shrinkage or expansion, since I built it, about 7 years ago.

cedarwoodron
Alternatively, if I elect to wire feeders with regular wire soldered connections, one article mentioned doing so on the INSIDE of the track rather than along the outside, for better visual effect. Is that a better method?

I would suggest the outside of the rail.  They can be hidden easily, and on the inside, you run the risk of the solder interfering with wheel flanges.  I've seen some articles, where the feeder was attached to the bottom of the rail.

Mike.

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  • From: Reading, PA
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Posted by rrinker on Thursday, January 04, 2018 12:18 PM

I've built two layout so far where the power source was powered rail joiners, and nothign but powered rail joiners. Now, my approach is perhaps unorthodox in that I made EVERY rail joiner a powered joiner. (I use flex track, not sectional, so not nearly as many joints as you think)  Next you are thinking about how much Atlas charges for those terminal joiners - well, I don't use those. I buy the regular joiners, and then solder my own wires. I do this at the workbench, make up multiple sets ahead of time. 

 I also solder SOME joints - like solder together two pieces of flex before forming a curve, and that soldered joint has feeder wires soldered to it. I never had an issue, even when painting the track - and I always slop the paint in around the joiners to make sure the rail is completely covered. no loss of power from the paint, and the paint should keep out everything else.

 On the contrary - having a set of feeders each of the three legs of a turnout (Atlas, so no issues with power on the frog side) meant I never had any power issues with them and I never hooked up my frog power wires because as it turned out, nothing would stall, even at really slow speed. You can never have too many feeders.

                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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  • From: North Dakota
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Posted by BroadwayLion on Wednesday, January 10, 2018 7:05 AM

LION runs DC. Is astually point to loop, or think of it as a long point to point that ends up back where it started from at 242nd Street.

The LEFT rail is common AND Ground. Has to be a hard ground to the building ground system otherwise stray voltage will drive you crazy.

Positive power on the right track moves train forward.

Negative power on the right track moves the train in reverse.

If you have gapped blocks any power supply will provide that power either in forward or in reverse.

SUBWAY LAYOUT OF LION has NO REVERSE... All trains must move forward.

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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