Control of Crossovers,...doubles & singles


beiland

Well-Known Member
Control of Crossovers,...doubles & singles

Exploring ideas for 'powering-up' crossover turnouts. Of course many of us would be well aware of our use of a double crossover on our layout planning (it just stands out), ….but perhaps less aware of the number of single crossovers we have designed into the plan. That was one thing I recently discovered while looking into controlling my turnouts,...I have a lot more crossovers than I originally recognized.

Like the prototype railroads I decided to try and limit the use of 'doubles' and try to make use of singles were possible, particularly when I read about the number of problems that could be encountered with doubles vs singles ( one of the reasons the big guys limited their use).

But the purpose of this subject thread is NOT to discuss doubles vs singles, but rather controlling these crossovers.
 
Probably most folks will be choosing to operate their turnouts with some sort of 'automatic' controller. I recall doing that years ago with a CD power unit, a single solenoid, and some sort of linkage I dreamed up. I can't recall the details of that linkage.

There are a wide variety on single and multiple motor ideas for operating our crossovers. Some will likely get presented here, and/or are available on a number of other internet sites.

I am particularly interested in manual control, and remote manual controls. Part of this interest is generated by the challenge of the situation, and some of it by non-electrical/computer simplicity.

Manual Control of Single Crossovers

In my original planning I had been going to utilize a couple of double crossovers by Shinohara that I had picked up at a train show a number of years ago. As I got to studying them, and discussing them here on the forum, plus running some experiments with them, I began to look for alternatives.

Turns out I had room (length enough) to utilize 2 pairs of single crossovers rather than the doubles. I also discovered that I could make very effective single crossovers using 2 Peco large size turnouts back-to-back. Here is a comparison,....Shino Dbl on left, then Peco large pair, Peco med pair, Peco sm pair,....
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I ran experiments with those Peco large pairs and was very satisfied.
So where I was going to have a dbl-crossover, I will now have 2 single crossovers consisting of 4 large size Peco turnouts.
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My dilemma now is how to manually control (from a distance) each Double (2) Peco turnouts of the single crossover with a single control rod/whatever.,..some sort of linkage situation.
 
My dilemma now is how to manually control (from a distance) each Double (2) Peco turnouts of the single crossover with a single control rod/whatever.,..some sort of linkage situation.
Have you investigated choke cables, cranks, and piano wire?
 
Yes I have looked at a lot of these cable, cranks, and piano wire.


Linkage Idea

Here is what I have in mind for a linkage to coordinate the operation of 2 Peco turnouts together. It's basically a stiff piece of metal strip that would be a little bit longer than the distance between the holes in those Peco throw bars . It would have two vertical 'post' of music wire welded at that exact distance between the throwbar holes, and they would be long enough to reach up thru the plywood deck (and roadbed) to operate the turnouts when the metal strip was rotated slightly. The rotation center of the metal strip would be the exact center between those two vertical post.

The rotating metal strip would bear against the underside of the plywood deck, perhaps against a very thin plastic shim for friction purposes. It would only need a single central screw mounted into the plywood deck to rotate about, and it would only need one push rod attachment to operate its rotation,...one control rod / cable to activate 2 crossover turnouts simultaneously.


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(that vertical pin would be centered in that metal strip & firmly anchored)
 
Decided to play with this idea late yesterday. My initial attempt to drill those very small holes for the vertical piano wires in the steel beam was a failure. That steel beam is to tough for those vary small drills,...broke several drills already.


I've several new ideas that I will try out tomorrow.
 
Dual turnout control fixture experiment


Since I was unable to drill that very small hole into the steel beam I began to think of of ideas of how I might attach the piano wire to the steel beam. I thought of a several that might be very possible including cutting off the tips of that beam and adding on dense plastic tips that could be drilled out for that piano wire.


But before cutting that beam and adding on tips I thought why not put a short piece of tube in those holes that could hold the piano wire. The holes for that tube fixture would be larger and thus easy to drill, and I could solder the tube in, then solder the piano wire inside the tube. I would make the tube fixture flush with the upper face of the steel beam so it would have no problem rotating while facing the flat plywood face.


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Wait a minute, why would I need a flush fixture tube when it would only be rotating a very small amount,....and inside the confines of the hole in the plywood deck needed to project the piano wire up to the turnout throwbar? No I could provide a tubular piece in that steel beam that could be a decent length to hold that vertical piece of piano wire, and it could project both up and down from the steel beam.
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Wait a minute, why should I have that vertical piece of piano wire firmly attached to the steel beam? How about if the piano wire could be dropped down from the throwbar into that tube fixture. Wow, that means I could install the turnouts to the deck above, not worrying about their height (with or without cork roadbed, then come along and drop the piano wire thru the throwbar , then down and engage the tube fixture.


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YES, ... it works !
 
Some Friction Ideas

Concurrently, I began to think of simple ways to reduce any friction of that connecting bar,.... just plain low friction plastic shims attached to either the plywood surface or glued onto the metal beam.

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made of plastic food container scraps
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No Longer just a Mockup

A few days ago I started a full scale installation of that experiment I played around with. I'm going to first work on just two of the crossover situations I have, that I wish to control the 2 turnouts of the crossover with a single control cable/rod.
And I have chosen 2 slightly different variations that offer a little special considerations;

1) One of the installation occurs in a back corner over behind my brick factory. It is a long curved peco on the mainline that pairs up with straight long single on the siding track. The 2 turnouts under discussion,...

A particular situation exist here because the hole in the center of the throwbar denoted by the other arrow is very nearly conflicting the the 2" heavy duty metal box beam below it, ....bolted to the wall of the shed, that holds up this entire deck piece of plywood.


2) The second installation is more straight forward as it involves a pair of long Pecos that are mounted on the initial ramp pieces of my stone arch viaduct. Those will be mounted on the PVC board forming this ramp, and the swinging control piece will be mounted on the underside.
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Crossover of Straight with a Curved Turnout

Yesterday was a very trying time. I ended up spending most of the afternoon working on just one of those single crossover situations,...and it is not totally solved yet.
( Situation #1 noted above)

It involves the linking of a curved Peco turnout with a straight large size Peco std straight turnout. I had hopes that this would not present problems, as I have another similar situation on the other side of the layout.

So here is my 'rocker bar' (named by dark2star) laid out on top of the crossover combo
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And here are the brass music wire receptacles glued into the 2 ends
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I installed this and attempted to operate it. I noticed a considerable binding in the rotation, that resulted in one of both ends not working in unison, AND in the binding restricting the the pecos internal spring not operating properly/freely.


Lets see what's wrong,...and what correction I might make??


1) Holes for the 2 brass receptacles were ever so slightly too far apart
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(notice the slight bend in the music wire trying to enter throwbar from brass receptacle)


I'm not exactly sure how this happened but likely as a combo of my distorted vision, and the ruler I was using since I did not do the measurement by location drilling down thru the throwbars of the turnouts themselves. I subsequently soften up the solder joints holding the 2 turnouts together, in an attempt to move them ever so slightly apart to match the receptacles in the rocker bar.


2) Brass receptacles were to tall. I had made them as tall as I thought possible to more fully support the music wire fro bending sideways. It made things too rigid thus exasperating other measurements, and contributing to the binding action. I subsequently cut down the length of these risers, and that helped by giving a little more 'springiness' to the music wire that was operating the turnout throwbars. I also experimented with using .039” thickness music wire rather than the more rigid .047” wire I originally used.
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3) My rotation center hold in the 'rocker bar' was every so slightly off,...I mean by only maybe by 1/32”. As a result my center hold for the rotation screw into the plywood deck's underside was also slightly off. I had know right up front that this was going to be a critical location, and my eyesight and centering capabilities had let me down here as well. Since I all ready had the centering holes drilled in the rocker bar and the plywood deck this was going to be a challenge to modify in order to determine its detrimental effects! I subsequently moved the turnout pair ever so slightly such that rotation screw hole in the underside of the plywood deck was not corrected. I unsuccessfully tried drilling the centering hole in the rocker bar just slightly oblong to allow it to work....not a good idea as it allowed to much play in that center hole location. I finally had to glue 2 pieces of very stiff plastic sheet over the old hold in that rocker bar, and drill a new centering hole.


Bottom line is what a cluster-f
 
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dark2star
Hi Brian
However, I like your idea of that rocker bar. The only thing is, the rocker bar runs along a radius, while the turnout control linkage needs to go on a secant (a line intersecting the circle but not the center). It will be aligned in one position, but not the other.

I think you had it correct here dark2star, PARTICULARLY for this combination of curved switch with a straight switch. The throwbars of these two are operating in two completely different directions, and this exasperates the differences in the distance between those hole centers in the throwbars of the 2 turnouts (and correspondingly the rocker bar ) making for problems,...that I thought would not be troublesome with such small movements that would be required.


Even while I think I can make it work, I don't feel so confident in the long range,...and being a relatively a back corner location that might be difficult to reach at a later date, I have to give this serious thought.
 
I think you’re correct on the geometry of the various angles being problematic,
(I came up with that all by myself!), but I think it could be done with some flexible connectors and a center pivot.
Being that it’s in a difficult to get to location I’d maybe give another thought to powered switch machines, even tho I don’t think that’s your preference.
I think someone on shapeways was making pivots and connectors but I can’t find them now.
 
I believe what I am going to do is 'prep' the situation such that I can easily switch back to individual turnout control in case my double control configuration gives me problems in the future,..whats that saying in the boy scouts,...BE PREPARED .

I have another mock-up experiment to try out tomorrow.
 
Moved Outdoors

Our temperature here in Fl warmed up nicely today, so I had been waiting to move this big deck piece out to my carport work bench in order to shave/file/sand a few of those cork pieces to a gradual grade them down to plain plywood level,....(keep that sanding mess outdoors)
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Here is that initial ramp section that begins the stone viaduct. And you will note it has another planned crossover mounted on it. At least that one is 2 equal size straight turnouts like my initial mock-up experiment that performed rather well. We will see about this one tomorrow.
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As I mentioned before I have decided to add a crossover on my viaduct ramp,...

2) The second installation is more straight forward as it involves a pair of long Pecos that are mounted on the initial ramp pieces of my stone arch viaduct. Those will be mounted on the PVC board forming this ramp, and the swinging control piece will be mounted on the underside.
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Here is the rocker bar for that installation with its two music wire receptacles at either end, and the pilot hole and centering bolt.



Here you see one of the ends and the three holes that mark the throwbar's center hole migration,
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You can see this is a very small 'migration' . Here are the oval holes I provided for the brass receptacles that will hold the music wire activators.


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This rocker bar fits on the underside of that PVC ramp,..






I still found that a bit too much friction existed between that steel bar and the plastic ramp material, so I added 3 very thin plastic spacers, one in the center,and one at each end,....that cleared up matters and it works just fine.


Now back to that first one that gave me many problems. I've got some new ideas.
 
Connecting Bar

So far I have utilized several different connecting bars / rocker bars for my crossover experiments/installations. I have a new idea that I will explain my reasoning for investigating. But first here are the 3,... I have experimented with.





1) On the far right is the steel bar with the brass tube receptacles to direct the music wires to the two turnout throwbars at either end. I utilized the steel bar as it was relatively stiff to both impart the exact small rotation,...and to follow the flat underside of the plywood deck. However it was so tough of a material I could not simply drill those VERY SMALL holes in the ends for the music wires,....broke several drills trying that out,...So I decided to use those brass tube receptacles.


2) In the middle is my second experiment, a thin-walled alum box shaped tube, constructed in a similar manner to that steel one. It was actually better at remaining total flat and following the flat underside of the plywood deck. I was still a little unhappy with some looseness of the music wire fit inside that receptacle tube, that would also fit the hole in the turnout throwbar,...


3) The third one on the left is my last experiment with that same boxed alum tube with just small holes drilled for the music wires. Even while I tried to drill very small holes for music wires, the very thin walls of the boxed alum bar allowed to much slop with the music wires.


That last experiment had me looking for some sort of 'boxed tube' that might be just a little bit stiffer, and would have thicker walls. I ran across a nice rectangular brass one from K&S, but I could find it in 20-22 inch lengths.


I think I have found a new tube for this rocker bar.
 
Rocker-Bar/Connection-Bar


Whatever we want to call it, its that bar that connects the two turnouts attempting to make them work in unison. I've experimented with several different configurations, documented above. The flat steel bar seemed to be the answer at first, but I found that it could bend ever so slightly in its length, producing some unwanted friction between its tips and the plywood deck it was swinging against. It also appeared to twist ever so slightly.


My next experiments with a boxed shape of aluminum taught me the value of 'rigidity of form' even with very small wall thickness material. I went looking for a somewhat similar shape that might be slightly thicker wall, and that could easily be drilled with a very SMALL hole to accept music wire of .039” or .047”. That left out steel as I had tried that before. So aluminum or brass became my objective. I could not find brass of at least 22” in length readily. But I did find this alum channel with a 1/16” thickness.
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I still had problems trying to drill .047” holes in it for the music wire, so I retreated to using brass tube receptacles as I had previously



I paid particular attention to getting all the hole spacing dimensions very exact, even using a drill press to assure exact perpendiculars.


I installed it and still found some slight binding. I finally found I could relief most of this binding by making the center pivot hole just slightly larger than the pivot pin.
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This arrangement is now working pretty consistently, BUT considering that this 'device' is back over in the corner that is not so easily reached, I have decided to provide that rocker bar with 2 control cables, one at either end,...the golden-rod blue cables here,..
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BTW, you may notice that this rocker bar now passes over two other pieces for of wire/tube. The one in the lower portion of the photo is a piece of music wire that is operating a single turnout outboard of the crossover pair. It creates a nice sliding surface for the rocker bar, but it might like to have a balancing surface on the other end, thus that short piece of brass bar on the other side of the central pivot pin.
 



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