Track Help Please Hi Guys, I'm looking to build an HO layout on a 4x8 sheet of plywood. There is a train show this weekend and I would like to pick up the track. I know there are different numbered curves, 18, 15 etc.... I have a double crossover that I would like to use. The rails are 1 1/4 inches apart, which curves would I need to use in order to have one loop, inside the other? (what number curve tracks inside, and what number curves tracks outside?) Thanks.