Rail gap location question DCC

[nobullchitbids]

Normally, with routing frogs, it is a good idea to gap any frogs which are opposed (in this case, the two frogs of the siding turnouts). An alternative is to wire the switch machines so that both turnouts are thrown for the same route at once. This automatically isolates any loco on the unselected route, since both rails will be of the same polarity.

The danger to avoid is where routing frogs are used and the switch machines can be thrown independently. Then it is possible to have the "middle" rails being both polarities at once -- NOT what you need.

[selector]

Bruce, have you been following Joe's DCC clinic? He talks extensively about short management, and gaps figure prominently in his philosophy. Now, his layout is quite large, while yours is more modest, so cacole's advice makes sense to me. However, Joe might take issue with the notion of no gaps. So would Randy, I believe. They would be concerned for fried decoders is you encounter a short with several sound-equipped locos on one secion of track. Of course, if you are not going to run the higher current drawing sound locos, then it would seem to me that gaps are probably not so important.

[Jacktal]

True that if you use insulated frog turnouts you don't need "electrical" gaps for this configuration.However,I'd recommend gaps to allow for metal expansion that can occur during temperature changes,although foam is quite forgiving in that matter too.

Also true that you have to use insulators with Electrofrog type turnouts but only the frogs need to be insulated.

[randyaj]

I think it also depends on what kind switches that you use. I used Peco insulated frog turnouts so I had no worries. But if I remember correctly with a live frog you have to isolate the switch and run jumper wires. Someone else can correct me if I have steered you the wrong the way.
Randy Johnson

[Blind Bruce]

Excellent points gentlemen. It sounds so logical now.
Thanks again,
BB

[MisterBeasley]

If you are using a Programming Track attached to the layout, that should be isolated on both rails. Some DCC systems use these.

Also, if you will typically be running one loco while the other sits idle on a siding, you might want to isolate 1 rail of the siding so you can shut off power to the loco when it is not in use. This will increase the lifetime of incandescent bulbs if that's what's in the engine for headlights, etc. Also, if you are running any other lighted cars, like passenger cars or cabeese, you might want to be able to shut off power to them, too.

[cacole]

If you're going to run only DCC, you don't need any rail gaps if the layout is going to be in the configuration you describe.

[Blind Bruce]

The foam is layed, the roadbed is ready, and I want to know where to place electrical gaps in the rails. It is a single circle of track with one runaround and several stub industrial sidings.
Overall size is 4X8 and is HO.
Do I need any gaps at all? would they be in both rails?
Only one operator and two locos.
Thanks,
BB