Hi, Hope that I can get some help here. I'm trying to "marry" two older DC layouts and have at least one reverse loop and possibly a wye to contend with. I've read everything that I can find and have bought two DPDT switches but am still totally confused as to where to isolate the rails and where to connect power from the switches. I'm wondering if I post a drawing of my layout here someone will be kind enough to walk me through making the correct connections. My wife would appreciate it. My grandsons would appreciate it and I most certainly would appreciate it. Thanks, Ron
Sure thing, post away! I'm in DC myself and have three turntables to contend with but the principles are the same. John
You need an auto reverse unit so as to keep it from shorting out. Sent from my iPhone using Tapatalk - now Free
Here's a good example with DPDT switches: http://modeltrains.about.com/od/track/ss/Reverse-Loops_2.htm Note the 4 gaps at the reversing loop to completely isolate it from the rest of the layout. A "center-off" switch may not be a bad idea. John
I believe the example linked here http://modeltrains.about.com/od/track/ss/Reverse-Loops_2.htm misses part of the story. It shows a DPDT switch on the reverse loop but none on the rest of the layout. Of course, most DC power packs have a built in DPDT reversing switch. That doesn't "count" however, because it is necessary to switch the polarity of the NON-reversing section independent of the feed going to the reverse loop. Actually, you could operate a reverse loop with a DPDT switch only on the non-reversing section but it would then be necessarily to run a train through the reverse loop in only one direction. Having separate DPDT switches for reverse loop and non-reversing portion of layout allows going through reverse loop in either direction. The automatic reversing circuit mentioned in another post is helpful but not absolutely necessary- if you're careful with your electrical toggles and your (track) turnouts. And a dead-end wye can be wired with a DPDT switch connected to the turnout that accesses the dead end so that the polarity of the dead-end is connected ONLY to the track switched into it. Throwing the turnout automatically switches the polarity so the train can exit.
I always reversed the main section the train is coming back to. Been doing it for years. That cab is dedicated to the specific train anyway. Another trick you never see in print...we wire a signal...single aspect, red, across the gap. One per end if you traverse both directions. If the polarity is wrong, the light is red...signals you to flip the receiving part. Turntables are dead easy. Just cut the pit rail perpendicular to the incoming track.....wire one "truck" to one rail on the bridge, the other "truck" to the other......change if backwards. Auto reverses the bridge as it passes through the gap. Now....if you leave power on, you can have a short as you traverse...bad thing to leave power on....just make the gap a section long enough to hold the "truck" on the ends of the bridge. I also use only pushbuttons to power roundhouse leads. You have to hole the button to run an engine in or out. No pit creepers that way. Dave
Ron, as I was in your boots a while back, you might want to do this first: Obtain/make a bunch of wires of different colors (white ones, black ones, red, green, yellow) with small alligator clips on each end about 8-12" long..You can then perform temporary tests of circuits like the reverse loop you're doing or make jumpers between tracks (obtaining power from say, main line to temporarily wire in a spur to see if you're gonna like it before hard wiring it in). You can do all the toggle connections (including the criss-crossed one on DPDT toggle) for the reverser section rails where gapped and not gapped with no regrets if something isn't jiving yet... Then when you can 'see' the logic copy them with hard wiring...If you're not happy, unclip em', reclip em' til you are...I find these to be essential 'tools' for MRRing...Mark
Hi all, Thanks for so many replies. I am trying to upload a drawing of my layout. It is in .jpg format but is 2.5 woo woo woo and the system won't upload. Says file too big. Any ideas?? Ron
