connecting switches back to back

Some locomotives have problems going through back-to-back switches. Now and then the wiring and/or insulated rails don't play well together.

Is there room for a short straight track between them?

I have given thought to adding a short straight track between.  I think I can do that without altering geometry by deleting a short straight track downstream, but that will also require taking out a short piece on an extended O-42 curve at another place (leaving a continuous O-42 curve) in the layout, which I am not sure I want to do. 

I had a similar problem with Ross O-42 switches and solved it, as ReadingFan suggested, with a short piece of straight (on both Gargraves and Lionel tubular lines). 

Jim

Or I have a fix that will cost less than a dollar!!  I have lots of switches that are back to back without a problem at all.  If you are interested, let me know and I will e-mail you the fix.

Alan

Bob, I'm no computer genius either, but I've figured the email out.  Just click on leavingtracks' name under his avatar, and on the next screen go to the right and scroll down till you see his email.

Alan,

Why not post the fix on the forum?

Charles

Charles....you have a great idea but the explanation of how to do it is very lengthy.  I have taken some pictures but by the time I decided to do so, all of my switches were in place with track..etc.  So...what I may do in order to help more folks without all of them having to e-mail me is to ask my friend that actually did the wiring on the switch to provide his pictures of the wiring diagram.  He lives just a few miles from me so I will contact him and see if he will help.

I will follow up with those folks that have already e-mailed me and also follow up here.

Thanks,

Alan

It looks like you have a power problem in addition to the inherent issues with having s-turns.

What is "direct power", and what is the source of that power?  Are you using a common ground scheme for powering trains and switches/accessories?  Are your power supplies phased, and all plugged into the same wall outlet?

The power loss and sparking indicates a phasing problem.

Alan, OK.  I got it!  Also see why it had to be emailed.  My switches are MTH, so I'll have to figure out where to put the micro switch to fit the mechanics.

Rob, You may be right about the phasing.  I sometimes use a separate transformer for switch power, but from the same wall plug (power bar).  The ground is common.  I'll see if I can turn the plug around at the power bar.

That "sometimes" statement would be a concern.

The "sometimes" is when I have a problem, I experiment to find a solution.  It could be that other transformer on that test was out of phase and was not common to the other one.  My description of the problems did not include the different configurations used to try and solve the first problem of power loss.

Switches that are back to back, (Installed with no distance between them allow for dead spots in track power to occur.   Each switch has a normally occuring dead rail section that with these Atlas switches is about 1.75", which is no problem since a three rail engine has two pick-up rollers (some have as many as four), loose power to one pick-up, there should be power available from the other.   Problem occurs when two dead spots match the roller spacing on the engine, no power from either pick-up.
This older Weaver E8 has a problem with the two switches,(back to back) pictured.


Note that the pick-up are spaced 14" apart.


The two electrical holes (about 1.75") in each switch are also 14" apart.


The hole,note dead rail curve piece, is 1 3/4"


There are a lot of variables, each engine has different pick-up spacing and each switch, cross, uncoupler section, etc., as installed, creates this (2) hole electrical problem.  There are solutions, the simplest is to adjust spacing accordingly. 

Bob....the micro switches can be mounted along side the switch or on top, just so the lever on the micro is actuated.

Alan

Bob,

   Part of the problem with many companies switches (turn outs) is that no R&D testing was ever done running the switches back to back or in multipules.  I  run the old Lionel 711 & 072 swithces, they take massive power, but were engineered correctly for back to back running.  On medium to small layouts they even work well with track power, on larger layouts they must be individually remote powered. These old Lionel switches also have enough metal in them to run all different kinds of engines and rolling stock, including Tin Plate.  Unfortunately very few of the modern low voltage switches actually work in this manner, the Ross switches are about the best of all modern low voltage switches.  I have tested just about every different companies switches, and keep returning to the old Lionel originals because they really do accommodate all different O gauge engines & rolling stock, even when set up back to back, they work perfectly when powered correctly.

PCRR/Dave

An old Lionel 711 and an old Lionel 072 set up back to back, working perfectly in the middle of my layout.

I did this a lot in a switchyard I had early on, all wtih Fastrack 72" switches.  I had no problems because of making them back to back - even monsters like a JLC Big Boy would go through them well (looking weird though, with all the twisting and boiler stick out.  However, with that many switches that close, locos that were prone to stall on switches due to not enough electrical pickups would, somewhere, every time. That got annoying.

Lee,

   Its not the engines, the FasTrack switches have to much plastic in them, those same engines run thru the old 711 & 072 Lionel switches without a problem, back to back or multipule.  FasTrack switches were engineered for modern engines and rolling stock, its to bad they were not engineered for all the different Lionel trains.

Sometimes its hard for me to understand why Lionel engineers design as they do,

they dropped the ball on the design of the 031 FasTrack, not fitting inside the 036 FasTrack also.

I waited a long time for them to special engineer the 031 FasTrack, instead they engineered it to match the 036 dimensional design, when they should have custom engineered the new track for the actual running inside the 036.  Although

I can use the 031 RealTrax inside the 036 FasTrack, I wanted a complete FasTrack Christmas layout, which is impossible now.

PCRR/Dave

but one switch just chatters in one direction and the controller will only throw it in the other direction.

This is not clearly explained, which is probably why no one has addressed it.

  --Joe

This is usually a switch problem, not how you connect them together.  For tubular track switches, this was a common issue that results from not having the proper insulating pins installed.

What you describe here is a fault causing the anti-derail to be active all the time.

Possible fixes:

Check the track to ensure the rails don't short to the isolated stub on the switch (the 2 short rails diverging as they exit the frog. There is no electrical contact on those rail ends for isolation, but there must also be a small gap to ensure the rails do not touch. In a couple places I put a small piece of duct tape around the end of that rail as an insulator. In extreme cases the rail on the switch or the connecting piece may be protruding, tap it back or grind it off to ensure a gap of about 1/16 inch.

Ensure the control is connected correctly at the switch terminals.

To determine which is the problem, remove the wires from the switch, with power to the switch, try turning the switch lantern then releasing it.

If the problem remains, it is a short in the track to the isolated rail stubs.

If the switch does not fight turning the lantern (buzz and vibrate) and stays switched, the problem is the connections of the controller itself.

Sparking is usually caused by sloppy wheel gauging and loose trucks contacting the center hot rail and the opposite outside rail at the same time.

I have fixed this by putting a strip of duct tape on the sides of the arcing areas (usually area C in Bobby's picture). This will took care of all my modern engines arcing. You can also glue some styrene strips to thicken the guard rails to keep the wheels away from the hot rails but this can cause issues with some PW equipment as the flange of some wheels is then too wide for the slot.

I have O-72, O-54, and even an O-31 switch in series for my yard, no more problems.

Bob,

   These men have given you some very good advise, especially Russell advising you as to what most to look for and the corrections needed for constant running.

Remember not all switches are engineered for all the different engines and rolling stock, investigate before you purchase.

PCRR/Dave

I figured this was another subject, so didn't emphasize.  Russel seems to be on top of it, so I'll trouble shoot as he suggests.

Bob, if you get hung up, email me (in my profile, click my name, look far right and scroll down)

I have lots of Realtrax and switches in use for years now.

I want to thank everyone for their considered, thoughtful and professional response to my questions.  This is truly a valuable forum.  I'm impressed, not only with the knowledge exhibited, but the truly passionate desire to help fellow railroaders (especially dummies like me).  As we old pilots like to say, keep the shiney side up.