I have an inner and outer loop and want to add crossovers do I have to isolate any rails?
Bill,
In general, it is a very good idea to gap the rails where the crossover occurs... at a minimum. Why? It is easier to isolate electrical problems between the inner and outer loop. It also allows you to operate two trains at once: one on the outer; and one on the inner.
For example: I have three loops on my layout. Each loop has a crossover, so I can pass from one loop to the other. I have an electrical gap between the crossover rails for each loop. Also, each loop has it's own power source (DC). Hence, I can move a locomotive from the yard, across each subsequent loop, until I reach the loop where I want to run a train. Once that happens I can run that train continuously, and still start another locomotive onto the next loop to run a train... all while still running a train on a different loop.
One day, I will switch to DCC, where trains are run independently of the power source. So the entire layout can be operated from one power source. HOWEVER, I will still maintain the gap in between each loop. These gaps will create "districts". So, if I have a shorting, or other electrical problem, it will be easier to isolate where the problem is, and still be able to run trains in the other districts, while I fix the problem area.
Gapping trackwork, especially crossovers, can get complicated in a hurry, depending on your needs. I tried to give as simple an answer as possible. Hope that helps.
Regards,
Jonathan
Out of the packaging, all HO Bachmann # 6 Remote Crossover Turnouts are wired for use in a DCC powered layout. The #6 crossover cannot be used in DC power layout without modification to the turnout's wiring beyond just gaps in rails.