Peter,
I insulated the rails to make sure that the blocks were isolated from each other.
Another aspect you should consider is block occupany detection, perhaps for future enhancements to your train. When I first started, I insulated all three rails of each track section, but somewhere along the way I started insuating the center rail and just one of the outside rails, and in some cases just the center rail. I cannot remember why I did this. Lazy?
In retrospect, now that I am 'computerizing' the layout, I wish I had insulated at least one of the outer rails of each track section throughout. BTW, the isolated outer rail provides the one of the easiest and best occupancy detection schemes, in case you are interested.
Glad to help (or at least try to . . .)
Alex
