Hi All, I am fairly new to this, and I need a little help putting together a track layout. I currently have a full circle of O54 MTH track and six 10" straight sticks that together form an oval. I would like to put together a track layout that can reverse directions on the outer O54 loop. So this means that I need to either utilize an "X" crossing or to have an inner loop with a spur back to the main outer loop. Either way it means four switches. What I need help planning is what size swithes do I need to get: O42, O31, or O27? Well the answer to that really depends on a lot of other factors. Without spend $80 on MTH's RealTrax software, or making lots of trips to my local train store, how do I go about figuring this stuff out?