Just getting into trains again with my sons.  Not ready for DCC yet, but i did buy two DC Bachmann train sets.  I know i can run both trains on one power supply, the trains will eventually catch up to each other.  What about if i plug two power supplies in and both sets of tracks are connected?  I ordered some track expander and hope to have the trains pretty far apart from each other.  Will i overload the track and short out the trains?  Thanks.