Newbie Question about 'Intersecting' layout

The most simple approach would be to electrically separate the inner loop from the outer loop by putting insulated pins in the center rail between the pairs of turnouts which form the crossovers between the two loops. You don't say which transformer you have. If it is a two-train transformer like an R, KW or ZW, connect the U terminal to the outside (running) rails, the A terminal to the outer loop center rail, and the B terminal to the inner loop center rail.

If you have two single train transformers, you can accomplish the same thing, but you must first "phase" the transformers by setting them to the same voltage (say 10 volts), connecting the U terminals together, and measuring the voltage from A on one to A on the other. This should be about

0 volts. If it instead reads twice the set voltage (20 volts with the example settings), unplug one transformer, turn the plug 180 degrees, and plug it in again. Put a dab of paint of one side of each plug so you can plug them in in-phase next time. Then connect both U outputs to the common outside rails, the A from one transformer to the outer loop center rail, and the A of the other transformer to the inner loop center rail.

With this setup, a separate control runs each loop. When you want to crossover the trains to the other loop, just make sure the trains are going the same direction and the two loop voltage controls are set to the same voltage. You will momentarily lose independent control while the locomotives cross the insulated joints between the loops, and if you are using two separate transformers, the trains may slow down while one transformer is temporarily supplying both trains, but I have not found this to be a problem in operating my layout.

Preserving independent control would require a more elaborate arrangement, dividing the loops into multiple "blocks" with selector switches to pick which transformer controls each block. GQ

Dennis, there are 2 clubs that I know of on LI- one is Trainmasters of Bablyon(sp), the other is Central Operating lines in bohemia. I don't have any contact info for them, but if you go to Nassau Hobbies in Freeport, I'm sure Charlie (the owner)can point you in the right direction.

I have 2 ZWs. From what you describe below, it sounds easier to run both off of 1 ZW??

With just the one ZW, do I have to make sure the voltage is the same when the trains cross??

Do you know of any detailed online reference pertaining to this??

Also, it sounds like you are running this on your setup. How nice is this type of layout?? Is it that much better than just having an outside loop that does not intersect?? I would have to purchase a few more switches to complete this layout and just not sure if it is worth it. Any thoughts....

Thanks, dr

Yes, using just one transformer would be easier. With smaller transformers, the load from two trains taxes the transformer and speeding up one can slow down the other. But at 275 Watts, the ZW can easily handle two trains. For the ZW, you'd want to connect one loop to the A-U outputs and the other to the D-U, so you'd be using the outer throttle levers with whistle controls.

They should be close, both to not have the trains jerk to a higher or lower speed, and because if the voltages are different, the train electrically causes a momentary short circuit of the transformer secondary windings between the two different voltage pick-offs. If the speeds/voltages are close, the "short" is only of a volt or two and will not be a problem. If the speeds are significantly different, then the "short" is of a higher voltage and more current flows, which might be a problem. But the durations are short, so I've never had a problem. It's more good practice, like not flooring the gas pedal every time the light turns green.

I don't. A poster on the newsgroup named "Bill" has a homepage with many tinplate train links, where you may find something. Kalmbach Publishing -

- has a good series of books on tinplate, including some electrical guides, if you would rather order a hard copy document.

I like it. It allows running two trains without needing constant attention, but also provides for interesting operations between the loops. I'll send you a .jpg of my layout plan off-group.

Dennis=A0Russo wrote: About every 10 years or so, my father and I unpack the lionel (O Gauge) and try and set something up. We just finished putting together a 8'x12' board and now are getting ready to design the layout. What I would like to attempt is an exterior loop that connects to the interiror loop (which has more going on than just a loop) allowing two trains to operate on the same track. However, I'm not sure how the wiring would work for such a setup (is it possible??). I envision the train on the outside mainly staying there, but with the option for it to switch to the inside (with the inside engine moving to the outside). Does anyone have any good online references for something like this?? Any help or input would be greatly appreciated!!

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