Chief....I hope you are paying attention because you need to see how I solved my problem with the MTH O-72 Realtrax Switches. Oh!! What's that? You say the Chief is off goofing off fishing at the lake? Anyway, here goes.
A little history about the MTH Realtrax Switch Problem:
The Chief and I installed a bunch of MTH Realtrax Switches on our layout. I have 12 MTH Switches and the Chief has a few more. When I started my layout, Fastrack by Lionel had not been born. About half way through the building of the second phase of my layout, I started to notice that the newer track did not fit as well as the old. The Chief was seeing the same thing as he connected his Realtrax. (Incidentally, someone in the last month provided a history about the manufacturing changes of Realtrax....THANK YOU!)
The Chief and I really became upset when the new O-72 Realtrax Switches started not to work. The Chief had switches that the switch motors were DOA. I opened a box of a supposedly new switch and discovered it had been reconditioned. Then I started seeing derailments at two brand new O-72 switches. Two out of my six O-72s would derail certain types of locomotives including BEEPS, Post-war, and Williams. After watching a small new Lionel Steamer ride over the frog and derail, I said something has to be wrong with that switch and not the engine.
Here is the MTH O-72 switch that was derailing random locomotives. Look at the gap between the back of the wheel flange and the guard rail. The car is an MTH tank car.
Needless to say when I measured the gap between the guard rail and the main rail on an O-72 switch, it was the same as on the O-42 switches by MTH. Logic says that on a straight section of track, the gap between the guard rail and the main rail would be the smallest. On sharper turns, the gap should be the widest.
To check to see if the gap width between the guard rail and the main rail was too large and causing the opposite wheel to ride over the frog, I put three (3) layers of 7 mil electrical tape on the guard rail, as shown below:
The tape effectively, reduced the space between the guard rail and the main rail. After several hours of running various types of locomotives and rolling stock through the switch at different speeds, not one derailment occurred. I sent the locmotives through the switch in reverse, too, with loads and without loads.
After a trip to the LHS, where I purchased .020 x .188 styrene strips, I added one to the face of the guard rail as shown below.
After several hours of hard running, not one locomotive on the Baltimore, Ohio and Wabash Railroad has had any problems negotiating this switch.
Now you know, Chiefie!!!