Layout/operating question

This is an awkward layout for two train operation, since each of the three loops shares track with the other loops, two separately powered loops are hard to achieve.  With the loops sharing so much track, independent two train operation will be difficult both electrically and in terms of collisions.  You could run one train on the big loop and another on the small or medium loop, but this would require that the second train be started and stopped often.

Bill

I don't see how you could ever get reliable two-train operation on that layout. You would constantly be dodging collisions between the two trains because they share so much track.

Gomez Adams thinks it looks just fine.

I'm pretty sure that layout design was intended for use with the old automatic block signals. Wired correctly with several of them (as well as non-derailing switches), trains would need to have their E-units locked in "forward" and then the block signal's functioning would cut off and re-apply power as the trains ran -- so they'd move in a stop/start fashion according to the signals. Provided the trains weren't too long and inadvertently deadlocked the block system. It probably was fine for postwar trains with four to six cars apiece. Not ideal for modern, longer trains though.

I was going to post earlier. Waited for some others to chime in. Looks like a disaster waiting to happen.

Could you simplify it by leaving out the turnouts and X overs and just raise the smaller loop up so the longer loop can just pass under it. Even if you used a tunnel on the lower loop where the upper passes over it. The train would only be out of sight for a few feet. 2 trains with no chance of a collision. You said it was going to be a Christmas layout.

Suggest going to this forum search box and entering "two trains one loop" in "contains all these words" box.

It will give you lots of specific ideas for running two trains around a Christmas tree.

In general, Z-Stuff and Dallee make products for multi-train operation over a single track, or even intersecting track.

Also CTT Oct 2007, page 74, shows the Z-Stuff application.

As @EricF says, engines should be locked in Forward.

However,

We also had a recent thread here on stopping and starting trains at intersections (without locking the engine in forward) for the purpose of multi-train operation:

https://ogrforum.com/...out-e-unit-reversing

It may give you some ideas.

None of the above will immediately answer your initial question about the specific layout you posted, but there are workable multi-train alternatives.

I run 4 street cars, over one figure-8 loop, without collisions (most of the time )

You could use the same 4 switches and two transformers, as you stated you have and have two train operation, by making two loops, one inside the other.  The 4 switches would provide two pairs of switches to connect the two loops at two locations and would allow moving each train to the other loop.  See diagram of my control panel below

Ignore all the extra tracks and look at the two loops.  Look at the bottom of the two loops and see two pairs of switches connecting the two loops.  There is only one button (red to go loop to loop and green to go around the loop for each throw), to throw each pair of switches to allow the train to go from one loop to the other.  With two pairs of switches this transfer is possible from both CC and CCW direction operation.  Isolated pins are required between the switches of each pair.

As others have pointed out 2 trains can be operated on 1 loop but that involves adding one isolated track section of 5 or so pieces of track and installation of a sensor track by isolating the out side rail of a track to be a trigger switch for a 12 volt relay for each loop.  This is a lot to build for a Christmas layout if it will be taken down after Christmas.  By the way, both of the loops in the control panel diagram I posted above, have 2 trains on 1 loop relayed systems.

An single loop oval and figure 8 provide a superior operating experience by allowing looping, running the figure 8 and reversing in both directions.  You could make and oval and figure 8 using 4 switches and add a second loop out side loop with 2 switches connecting the loops as in my diagram.  2 trains on 1 system can be added to one of the loops allowing 3 train operation or to both loops giving 4 train operation if you want to get fancy.

The link below shows how I built the whole layout (pg 1, post 1 bottom, has table of contents) and 2 trains on 1 loop is on page 1, post 8c.

https://ogrforum.com/...ra-027-layout?page=1

Charlie

@Bill at the Beach posted:

My question is WHERE do I put insulating pins and WHERE do I attach lockon for second power source. Power is a 275W ZW transformer.

Thanks again!

The simple answer to the question is that the insulating pins go where the divergent paths of the two turnouts connect. On the center pin. This should isolate each loop. If those are non-derailing switches, you will also want isolating pins on the return rails that go to the frog. (The two rails in the center of the "vee")

I would put on a total 4 lockons, but that is just me. One each on the long runs of tangent track. From top to bottom, in the center of the layout (Throttle A, Throttle B, Throttle A, Throttle B)

This will do the minimum to get power to each loop independently. If you want to used the shared track by both trains, then things get more complicated.  There is lots of good advice for that elsewhere on the thread.