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reverse Loop

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reverse Loop
Posted by WardR on Tuesday, July 16, 2013 4:06 PM

Hello Railroaders,

 

Hope everyone is well. I have a reverse loop we are working on coming out of a helix and Im not sure where to put the gaps and how many reverse loop units I will need, its not a simple in and out loop, I have drawn a picture, im hoping some of you guys with that knowledge can help me out, I truly appreciate any input you all have.

 

Thank You!!!

Ward

 

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Posted by richhotrain on Tuesday, July 16, 2013 4:18 PM

Ward,

Where's the picture?

Rich

Alton Junction

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Posted by WardR on Tuesday, July 16, 2013 4:23 PM

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Posted by WardR on Tuesday, July 16, 2013 4:23 PM

It must have not loaded the first time, hopefully you see it now?

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Posted by richhotrain on Tuesday, July 16, 2013 4:37 PM

Ward, perhaps I am not viewing your drawing correctly, but there does not appear to be any reverse loops in what you have drawn.

Where do you feel that there is a reverse loop?

Rich

Alton Junction

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Posted by floridaflyer on Tuesday, July 16, 2013 5:00 PM

Agree rich.  assuming that his entrance tracks do not have another reverse loop somewhere beyond the diagram, it appears that the + and - are mixed up on the two tracks coming in and leaving the track in question. 

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Posted by Soo Line fan on Tuesday, July 16, 2013 6:00 PM

Looks like the polarity on one of his mains needs to be changed but I would like to see the rest of the layout.

Jim

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Posted by richhotrain on Tuesday, July 16, 2013 6:06 PM

Soo Line fan

Looks like the polarity on one of his mains needs to be changed but I would like to see the rest of the layout.

Yeah, I would like to see where those two tracks with the arrows on each end are coming and going.

Rich

Alton Junction

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Posted by WardR on Tuesday, July 16, 2013 9:24 PM

Hi Guys,

 

Thanks for all the repsonses, Im going to get a better image that shows it a little better, those entry points are coming up and down from the helix. let me see if i can get a better image and post that , so it makes better sense.

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Posted by richhotrain on Wednesday, July 17, 2013 6:02 AM

floridaflyer

it appears that the + and - are mixed up on the two tracks coming in and leaving the track in question. 

Either that or, somewhere else down the line, the OP felt the need to wire those two tracks the way that he did.  That's why we need to see a more complete track diagram.

Rich

Alton Junction

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Posted by WardR on Wednesday, July 17, 2013 7:43 AM

the lines marked with polarity are a double track continuous main line loop and that the polarity for that is correct, I  guess the issues comes into play on the actual loop.

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Posted by MisterBeasley on Wednesday, July 17, 2013 8:27 AM

Are there any crossovers on the double-track main line leading out of this area?

I agree with all the others - nothing in this diagram is a reverse loop, but if there's a crossover to the right of the diagram, then there could be.

It takes an iron man to play with a toy iron horse. 

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Posted by Soo Line fan on Wednesday, July 17, 2013 8:47 AM

Ward,

Something here does not make sense, at least to me. If what you are saying is the 2 mains shown are connected at both ends to form a continuous loop, you have something marked or wired wrong.

On every continuous loop, the outside rail at any point will be the same polarity and the inside rail  will  be the opposite polarity. In other words, if the outside rail of a continuous loop is set / wired to positive polarity, everywhere on the outside rail must be positive or a direct short will result.

Looking at your diagram, if we close both ends of the loop, a direct short would occur. The top rail shown on the upper main should be the same as the bottom rail of the lower main.

Jim

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Posted by floridaflyer on Wednesday, July 17, 2013 8:54 AM

If the loop in question is connected to two continuous mainline loops then the loop in question would be a reversing loop and would have to be gaped on both rails on the divergent  tracks coming off  both mainlines. (I think)

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Posted by WardR on Wednesday, July 17, 2013 11:31 AM

That is correct, so the issue comes into play , what happens if we have 2 engines going into the loop at the same time? I know that may be slim that they hit the same spot , but if we are using cars with metal wheel sets this becomes possible, if the trains enter and exit the loop at the same times would we not have a short? and if so how do we handle that sort of situation. all the diagram's for reverse loops show only one way into a reverse loop and the gaps are cut on the turnout going in, so the chances of 2 trains shorting cannot happen cause they would collide at the switch, so one has to wait, but when we have multiple ways into a reverse loop how do we control this situation?

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Posted by doublehelix on Wednesday, July 17, 2013 1:10 PM

the upper track is a circle and the lower track is also a circle - they are concentric circles - in other words they are a double track main line. their polarity is correct because crossover polarity is correct.

there are crossovers before and after the polarity designated tracks.

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Posted by floridaflyer on Wednesday, July 17, 2013 1:32 PM

Once it was clear that there were two main lines not one, the loop in question is indeed a reversing loop and must be isolated. confusion occurred when it was unclear that there was two mains. The polarity is indeed correct for two main lines, that however was not clear at the outset. 

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Posted by richhotrain on Wednesday, July 17, 2013 2:01 PM

Wait a minute.  Now, I am more confused than ever.

Does each line represent a track, not a rail?

Rich

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Posted by doublehelix on Wednesday, July 17, 2013 2:09 PM

each line represents a rail

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Posted by richhotrain on Wednesday, July 17, 2013 2:15 PM

OK, that makes more sense.

So, when reference is made to a double main line, are we just referring to the four horizontal lines in the middle of the diagram with the arrows on each end?

Rich

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Posted by WardR on Wednesday, July 17, 2013 2:25 PM

Thats correct

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Posted by richhotrain on Wednesday, July 17, 2013 2:49 PM

All things considered, I think we need a fuller track diagram.

Rich

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Posted by Soo Line fan on Wednesday, July 17, 2013 3:28 PM

At least we are making progress Laugh

Jim

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Posted by richhotrain on Thursday, July 18, 2013 4:51 AM

Soo Line fan

At least we are making progress Laugh

LOL

Surely but slowly.

The power of these forums is to rapidly exchange ideas and advice on technical issues.

But the exchange of ideas can be slowed by the need on both sides to perform the other duties of every day life.

It will be interesting to see how this particular issue plays out.  The ball is in the OP's court.

Rich

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Posted by WardR on Thursday, July 18, 2013 7:03 AM

I can understand how everyday life does hinder things, its hard sometimes to get the information over as no one actually sees the entire layout.

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Posted by Soo Line fan on Thursday, July 18, 2013 7:26 AM

richhotrain
But the exchange of ideas can be slowed by the need on both sides to perform the other duties of every day life.

WardR
Duties of everday life? Dude not for nothing but what are you talking about

I do not mean to speak for anybody else, but I took it as you, me, Rich and everyone here has, or should have, a life outside this forum which takes priority over discussions. Some time earning a buck, personal chores or responsibilities can cause responses to be slowed.

Jim

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Posted by WardR on Thursday, July 18, 2013 7:42 AM

Hey , If that the case than I totally agree!, I never expect anyone to get back right away, frankly I'm amazed at how fast people do respond. Sometimes things get lost in emails back and forth and I agree, its tough to drop our everyday life. I do appreciate everyone's input on this site and always have!! I've always found fellow model railroaders eager to help a fellow railroader and appreciate that. I'm sure my team will work this out either way, but there are so many amazing modelers out there who have great ideas. I had posted on this site a few years ago about a reverse loop situation and several guys amazed me with their ideas on reverse loops. So not to offend anyone, just not sure how much more we can layout as the most difficult part is sometimes relaying the information as these things can become complex.. Thanks again for any input anyone may have. This reverse loop is at the top of a 4 rack double helix the rest is as double helix has mentioned a two line track layout.

 

Thanks again for anyones ideas or input.

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Posted by floridaflyer on Thursday, July 18, 2013 8:47 AM

So the bottom line is, gap both rails at the turnouts divergent track leading into and out of the loop  from the mains. One reversing unit will do the job. As mentioned, two trains in the loop at the same time could lead to shorting problems.  Have fun

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Posted by WardR on Thursday, July 18, 2013 9:01 AM

Yeah, that's what we came up with also, but tried to figure out a way to avoid the possible short . by maybe adding an addtional reverse loop unit outside the loop creating another loop. Well. thanks again for the input..

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Posted by richhotrain on Thursday, July 18, 2013 10:21 AM

Soo Line fan

richhotrain
But the exchange of ideas can be slowed by the need on both sides to perform the other duties of every day life.

WardR
Duties of everday life? Dude not for nothing but what are you talking about

I do not mean to speak for anybody else, but I took it as you, me, Rich and everyone here has, or should have, a life outside this forum which takes priority over discussions. Some time earning a buck, personal chores or responsibilities can cause responses to be slowed.

Jim,

Thanks for that support and, indeed, that it exactly what I meant.

I certainly hope that I did not offend the OP in any way because my comments were meant to be positive.

Rich

Alton Junction

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