Reworking the layout

[Terry Toenges]

[jward]

NOW it"s compleat.

[Kemptown Branch]

Wow, that is awesome! What kind of sauce are you going to put on it? Marinara, Alfredo, Meat...

In all seriousness though, good job doing that even with the limitations of set track.

[Terry Toenges]

I prefer Alfredo. Those are HO water tanks, sand box, and freight platforms. I'll have to build those for On30. Anyrail's selection isn't the greatest. I was just trying to get some ideas here. The four buildings in a row are O scale. I wanted to have tracks where I can set my rolling stock rather than keeping them in my cabinet. I have two Moguls, a Heisler, and a Porter for locos. I don't know how many cars I have. I like it with the turntable now that I have it in there. I couldn't make it work on the other side.

[Terry Toenges]

Still tinkering with it.

[WoundedBear]

Gonna use two reversing modules? Where do you plan on gapping it?

Sid

[Terry Toenges]

I have two of the modules. I have to figure out the gaps yet. I don't know if the crossings will have to figure in on where I put the gaps. I'll have to do immerse myself in some reverse loop reading for a while. It's been a long time since I've "studied" reverse loop info. I understand the basic principle but this layout isn't the basic reverse loop.
On the wye., I'm guessing at the short piece behind the brown Acme building  and the curve right across from that should do. I know I'll have to keep that inside oval all isolated. It's going to be tricky for me.
On the reverse loop, I was thinking at the little short piece right after the turnout on the right side.
I'll also have to isolate the outer loop from the middle one.
I don't know if this whole set up this way will be possible to do with these two reversing issues.
I'm open to any suggestions from anyone. I haven't done any reverse loops on any of my previous layouts.

[jward]

DC or DCC? It makes a difference in how you approach wiring.

[Len]

Just think of the crossings as two electrically seperate pieces of straight track laying on top of each other. It makes figuring out the gaps for the reverse modules a lot easier.

Len

[Maletrain]

Assuming DCC, it doesn't look that hard to gap for reversers.  The big loop can be gapped between the two diamonds at the ends (without regard to the diamond between them).  The wye can be gapped on the two legs of the turnout where they come together from the two directions on the inner circle to go out to the middle circle.  That way, you won't have to worry about trains being longer than the reversing sections.

[Terry Toenges]

I will have to cut gaps in the crossovers right? Say I have a train running clockwise on the outer loop. If I have another one running clockwise on the middle loop, and send it through the reversing sections to reverse direction so it runs counter clockwise on the middle loop, that would cause the outer loop to reverse also if I don't cut gaps, right? I sometimes have a hard time keeping these things straight in my mind.
I don't know if that is right either, now that I think about it because it seems like then it would need another reverser to keep it from reversing if the crossings didn't have gaps.

[jward]

That's just one of the questions whose answer will depend on if you run DC or DCC.

[Maletrain]

Terry, it's (past) time to tell us if you plan to run this layout on DC or DCC!

The logic for "reversers" is different, because, with DC, you need to reverse the track polarity to change the direction that a locomotive is running.   So, the whole layout needs to be able to "reverse."  And, if you want to be able to control more than one locomotive at at time, you need to have then running in different blocks, all of which need to be able to reverse independently of each other.

With DCC, multiple locomotives can run in different directions at different speeds in the same block, because their direction and speed do not depend on track "polarity" (actually A/C current phase) and the voltage is always at max.   A computer ("decoder") in each locomotive rectifies the A/C and sends variable DC voltage to the motor in each locomotive, controlling it independently from all other locomotives. The only issue is that track that loops back on itself (so that it makes a loco run in the opposite direction on the same track it came in on) will make rails meet out-of-phase and cause a short circuit.  Gaps in the rails prevent a short circuit until a locomotive bridges the gaps.    So, you need to have just one isolated section per segment of direction-reversing trackage that can have its phase reversed while the locomotive is in it, so that it does not create a short either going in or coming out of that segment.  That can be done manually with a double-pole, double throw electrical switch in the track feed wires,or with an electronic auto-reverser module that senses the short as it occurs and changes polarity in about one millisecond, rather than opening a circuit breaker.

So,which are you planning to use?

[Terry Toenges]

I assumed everyone knew it was DCC. Sorry if it wasn't clear. On Aperil 25th, I spoke about using the crossovers which only come in DCC. On April 27th, I said I already have #4 and #5 DCC turnouts. My On30 Moguls, Heisler, and POrter are DCC. I have two Bachmann auto-reversers. I'm going to get a decoder installed in my HO Thomas for when the kiddies are here.
So the track polarities will remain constant then. Polarity is one way on the outer ovals and the other way on the wye section oval and reverse loop. I have one loco going clockwise on the outer oval, Another loco, going clockwise, heads into the reverse loop and comes out and heads counter clockwise in middle oval and it will be okay. Right? I just want to make sure I have it right in my mind so I don't have any "Uh oh" moments after i have the track all down.

[Maletrain]

OK, then my advice on where to put the reverser gaps is good. 

In a very early post, you had said something about hooking it up to DC.  And, you recently were talking about putting gaps between the middle and outer loops in a manner that seems to indicate DC, rather than DCC:

"I will have to cut gaps in the crossovers right? Say I have a train running clockwise on the outer loop. If I have another one running clockwise on the middle loop, and send it through the reversing sections to reverse direction so it runs counter clockwise on the middle loop, that would cause the outer loop to reverse also if I don't cut gaps, right?" 

Actually,  no, not right for DCC.  There is some confusion by using the word "loop" for what is basically a circle that the train can run around without going back on the same track in the opposite direction.  Your outer and middle circles do not need to be isolated from each other for DCC to have one train run clockwise and the other run counterclockwise without causing a short circuit at the crossovers, and those circles do not need to be reversed for any reason.  (But, they can be isolated on different circuit breakers, if you want to make sure that a short on one circle doesn't stop the trains on both circles.)  For the middle circle, the part you are calling the "reversing section" that will "reverse direction so it runs counter clockwise on the middle loop" is where you will need an isolated section with some mechanism for reversing the phase of the DCC wiring.  Note that reversing the phase of the DCC AC voltage will not cause the locomotive to change direction.  That is a DC concept, not a DCC concept. 
 
The inner circle is connected to the middle circle with a wye, so that a short would be created where the turnout connecting it to the middle circle splits to go either way on the inner circle.  To avoid that, gaps need to be placed after that turnout, before you get to the other 2 turnouts in the wye.  The easist way to handle the inner loop is to just put the whole thing on the electrical reverser, since in only connects to the other parts of the layout through that one turnout.

The 3 diamonds that you have do not figure into the logic for direction changes and the reversers that those require.  However, if you think about how to wire a diamond, you will see that it must create 2 short circuits unless the rails are gapped to isolate where the rails of opposite phase cross each other.  Most commercial sectional track simply makes those relatively small parts out of plastic, so they are none conducting.  If that causes a problem with small locomotives that have limited power pickup areas, then  you will need to have diamonds with metallic rails that have isolation gaps and electronic reversers to (nearly) instantly match the polarities of the two rails for the direction of travel though the diamond.  I mention that because you did say something about using small locomotive types that might have a problem with electrically dead diamonds.  But, I work in N scale and don't have any experience with your engines types in your scale, so you will need to get that advice from somebody else.