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Catenary Poles


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"What is the proper distance between poles?  


Did a little research and here is what I found




"Catenary" is a geometric term that refers to the curve or sagging shape that is created when a cable or chain is hung between two poles. There are formulas and equations that are used to calculate the optimum performance which goes far beyond our purpose.

Our Purpose

“We just want to know what looks right”.


In order for us to know what looks right we need to understand the factors involved in establishing a catenary rail systems.  

Fundamental Components


Components in an electrified rail system.





Cantenary wire


Contact wire

Transformer/Power station


Catenary system What's it doing


The main objective is to suspend the contact wire to supply power to the train. The effect (sagging) on a suspended cable as defined is called the Cantenary”. This effect has to be addressed for the purpose of railway operation and is done so by the dropper wire. This dropper wire supports the contact wire so it remains level or parallel with the track. There are limitations to the number of dropper wire used in a line up which starts to answer the question of how many and how far apart do we space the mast/poles. This discussion can delves further into the engineering aspect but we can start to realize that the design of the Cantenary system can be complex. Although these factors can be complex the fundiments can lead to our answer.  


All of the factors above point us to a basic concept. The cantenary system and its design support different types of trains and rail system. This understanding will help us to emulate actual prototypical railways based on the trains we are operating or incorporating into our layout.


Now, the gating question for us is the distance between cantenary poles/mast. It is not a set number but an engineered number based on the types of trains utilized and the track configuration itself. The distances are affected by the terrain or track layout. Curves and hill may require poles/masts to be as close as 50 feet where as straight aways can support distances as much as 210 feet. It varies widely.


There are other factors that play into the answer but the basic objective is maintain proper alignment with the track and contact wire. You must reason into those factors and apply it to your layout and install the poles/masts accordingly.  


So as you finish your layout just consider what it will take to keep your contact wire level and parallel to your track and install the poles/mast based on that requirements and you will be right.


Based on observation from Youtube and other railfan images it looks like the average distance is 312mm apart. I get this value from the spacing in the images. Most often I can catch a frame that shows the locomotive and 1 half of a car between two catenary poles.


Using this as reference I found that the EH500 and 1 Koki 106 will fits on 1 248mm + 1 64mm unitrack piece. This totals 312mm and converts to 160 feet give or take. That sounds about right in the real world.


Hopefully it gives a little insight to the question and maybe someone will find the written standard to clarify it 100%



Whats available


Kato Catenary lines consist of 5 products (Kato is all I use)


Installation Accessory





23-056 Cartenary Pole Base Set

These are needed/must to mount on the track 23-057,23-059,23-060) 23-061 comes with its own mounting piece.

Whats inside: There are 16 mounts for ground/track installation and another 16 that can be used on viaduct piers. The number a package supports

depends on single or double track usage.


Catenary Pieces





23-057 Arch-Shaped Cartenary Pole For Double-Track Plate

Whats inside: There are 10 poles total. 5 type I and 5 type 2.

This style seems to be in high traffic rural/suburb areas





23-059 Cartenary Pole Set


Whats inside: There are 16 poles total. 8 type I and 8 type 2.

Type 1 and 2 are used to navigate around single track curves.


This style can be used on ground or viaduct. This image depict a double track configuration

but these are single units. The 23-056 flat mounts can be snapped together to create the

depicted image and the single viaduct tracks are mated side by side using the pier mounts from

the 23-056 mounts.    





23-060 Cartenary Pole Set

Whats inside: There are 8 poles total..

These units are one piece poles that utilized 2 flat mounts (23-056) to bridge a two track configuration. The spacing

is shorter than the 23-061 units.  





23-061 Double Track Wide Cartenary Poles


There are 10 poles total with 10 mounts. There are 8 standard masts with 2 tension weight style units. This unit is slightly wider than the 23-060  in order to encompass the wider double viaduct.


Note: The 23-061 comes with the standard ground level mount. It is not packaged at the image is displayed. The image depicts the wide catenary mounted on a wide mount pier stand.This wide mount pier comes in the V12, V13 V14 varaition sets or the 23-020 pier set. The 23-061 cantenary will not fit on the standard pier sets like 23-018. If you order extra 23-061 for elevated ducts you will need the 23-020 piers.

Pier set


Smaller 23-018 and larger/wider mount 23-020

23-018.jpg  23-020.jpg  




Here is the plan outline.


 1. Catenary Poles –  Kato –  4 types 23-057,23-059,23-060 and 23-061.


 2. Wire selection –

   a. music/piano wire .005 / 36 AWG

   b. buss wire .00795 / 32 AWG

   c. buss wire .005 / 36 AWG

   d. buss wire .00314 / 40 AWG


 3. Setup configuration 1

   a. Install basic message wire/catenary wire setup

   b. Create tension method  


 4. Setup configuration 2

   a. try simple tie of contact wire mounting  

   b. Build soldering jig if simple tie method fails

   c. solder contact wire

   d. install contact wire


 5. post images.

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inobu - Great information and timely for me. I'm getting the parts for my diorama together and I was just trying to figure out the spacing of the catenary poles and here it this post with the information I'm seeking! Am I lucky or what!

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I think the cantenary is a signaficant element in the Japanese modeling layout. Without it the trains cannot really operate. Detail is critical in modeling and represents the amount of effort applied.

With that I started to think about what it would look like with wired cantenaries and founf a simple visual option.


What was a pain and nusance came to be quite handy. I ran a few strans of wonderful hair that I find all over the place. Those of you that have those wonderful women in the house know exactly what and how much I mean.



Here is an example of what it llooks like.

[smg id=626]

I 'm thinking that a reel of minature dc motor winding may be just the size but getting the catenary sag and dropper wire is the challange. I'm going to think about how to get that but I really think this is that finishing touch.





Did a little research and it is doable. The wire should be around 36 AGW  which is .005 inches. Hair is about .004". In N-scale this is about 3/4 " which is close enough for the modeling eye. If one goes crazy they can solder the dropper in place. There is enough room on the insulators to wrap around going from one pole to the next. If you load up all the insulators it looks nice.


[smg id=627]


I'm sure I will be doing this on my layout. I'm going to get the wire this week to verify its workability also she wont have to wonder why I'm staring at her hair in admiration.



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So you're using your woman's hair as catenary?


Holy schnikes, man.


LOL, its just a conceptual test. I'm going to use 36 AGW wire. The same kind they use to wind minature DC motors.


As for the Ginga Models, availibility is one issue but the cost is really going to be high. A 248 mm pack has 2 catenary/contact wire per pack and its going for what looks like $13 USD. It is going to be extremly costly when you use a double catenary that has 7 insulators and I thnk they only have the catenary/contact wire.


The sets cost more that the unitrack it self. Over all it would be cost prohibiting for most.


I checked into the wire it self and you can get a spool that is 3300' for $59. Smaller spools are available and cost less. If you mess up or crimp the wire all you have to do is cut it and unwind another piece. Crimp or screw up on the Ginga etching you will have to spend another $13.


It looks good and seem easy to hang but the cost itself and potential cost in error seems too high of a proposition.


I'm going to test out the wire and the potential of soldering the dropper (If some one wanted to go to that level.)

there are a lot of different type of wire, cloth coated, insulated. Just need to see what works best.




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Looking forward to your experimentation. For me, I'm only looking to wire a smallish diorama, and so the cost of the Ginga wire might be worthwhile (since it won't cost a whole lot) if it looks good. Nevertheless, I'm extremely interested in what you're doing!

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I still hate Kato for making the poles too tall.

You'd have to do extensive mods to actually make the pantographs get anywhere near the contact wire.


Actually, seeing the pic here makes a little more sense now... the double-wire is meant to support the catenary wire and not the contact wire... makes more sense now... but a lot of effort to hand model... and the cost of ginga's sections is a little excessive.

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Here is what I discovered/found today from a site that runs live catenary trains. The author is Noel T. Holley who models a HO scale setup. In his article he outlines the material he uses for his live catenary setup.


In his article  he point out that piano or music wire is a better solution due to its properties.


Here is what he has to say:




My catenary is built of .015 piano wire. It is a spring steel wire which is available at most hobby shops, especially those which sell model airplane supplies. It costs 10 to 20 cents each for three foot sections. I recommend this type of wire because it is sold in straight sections, it is very strong, and if it is bent into a shape, it will hold that shape. In addition, it is inexpensive. Thin brass wire is used for the hangers which link the trolley wire to the messenger wire. Steel does not solder easily with the commonly used lead-tin solders. It order to solder it effectively, one of the types marketed as low temperature silver solder must be used. STAY-BRITE brand is very good and many hardware stores carry that or equivalent products.


Types of wire used by others in building catenary include phosphor-bronze, spring brass, and nickel-silver. These types of wire have a much higher electrical conductivity than steel and nickel-silver is resistant to oxidization. These wires also have the advantage of being easy to solder, but it is difficult to straighten them. They are sold on spools or in coils and they tend to coil or snake unless put under tension. The tendency to coil makes it difficult to use these wires on a jig. The need to apply tension to combat snaking makes it difficult to build a prototypical sag in the messenger wire. Copper wire is not useful in building model catenary because it is too soft and it tends to stretch if put under tension.


His information gives a little insight to what we need. In another section he talks about how the catenary sags and what happens which is important in our experiment.




On a prototype railroad, gravity exerts a significant downward pull on the catenary Even though the trolley wire is under 2,000 to 8,000 pounds of tension, it would sag if it were not supported by the messenger wire. In order to provide support, the messenger wire is designed to sag and is under roughly equal tension, If, however, the messenger wire is excessively tensioned, it will pull the trolley wire upward at midspan. The trolley wire will then no longer be horizontal, it will be distorted into a wavy pattern which rises and falls like a hog's back. Hogged catenary could be seen on prototype railroads when cold weather caused the messenger wire to contract. I observed this on the Milwaukee, and a consultant study noted it on the Pennsylvania. When this occurred, wire maintenance crews had to adjust the wire tension in order to make the trolley wire level again.





Gravity does not operate to scale. As a result, there is no significant downward pull on model catenary There is nothing to counteract tension in the messenger wire, thus any tension is excessive tension. It has been my experience that a messenger wire with any tension on it will pull the trolley wire upward in mid-span and hog the catenary some extent. Milwaukee modeler Keith Newsom builds his catenary out of phosphor bronze wire. He found that he could have some tension in his messenger wire and still get the trolley wire to lie flat. This was accomplished by cranking up the tension on the trolley wire.


On a model railroad, tension is required on the trolley wire. Without it, will cause the catenary to deflect upwards and to the side in midspan. If the catenary is capable of deflecting upward more than one scale foot, the result may be poor electrical contact. If it deflects sideways more than two scale feet from track center, the pantograph may come off the wire and hook the catenary with its horns. This will result in a bent pantograph and possibly torn down catenary The amount of tension which is required in the trolley wire can be determined by trial and error. The required amount of tension becomes greater as the pole spacing becomes greater. Up to a point, steel wires will stay tight, if they are strung tight. If pole spacings greater than about 120 scale feet are used, the catenary will need spring tensioning. According to some people, the amount of expansion and contraction in bronze, brass and nickel-silver will make spring tensioning a necessity if those wires are used.


Full article http://webhome.idirect.com/~helmutw/milwrd/models/cat.htm


The important point one has to consider. Gravity works everywhere even in scale. In order to see the effects of catenary or allow the effect to be applied he has to use a smaller diameter wire on the droppers. The weight of the larger contact wire will place tension on the thinner dropper and we will see the true effects of gravity. All factors in prototypes applies even in scale. The factor we miss is applying the correct or scaled ratio toward which ever device or element. A N scale bolt has an applied torque levels just as in the prototype world the fact is we just don't have the tool in the correct size to apply it.      


What he has pointed out is important information.

So here is what I did today.


I stopped by a wire distributor to get a look at some 36 gauge wire. Unfortunately they only has 32 and 40 gauge wire. The 40 gauge wire seem to break rather easily and the 32 guage looked a little larger than I wanted. But seeing the 40 gauge give insight to the above issue with gravity. The weight of a larger gauge wire will apply tension on the smaller gauge wire.


I will try to get the right gauge wire to complete the first setup.


So far I have come to the conclusion that modeling the catenary poles come on two setups. The first being a simulated look by just straight wiring as I did in my my test configuration above and the second being the full catenary look as suggested in the article.


In either case I will present both configuration and one can choose to their liking.



For anyone who might ask "Why all the trouble?"


As I stated before the wiring gives an added appeal and presents a form of realism intriguing to the viewer that's what makes it worthwhile for me to explore.





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You can make catenary in N scale, but the practical question is how do get to the tracks with catenary?  How do you clean the tracks? How  do you reach a car in a yard?  You don't have the space to put your hand into a yard and or under the catenary and turn your hand. At the most you can wiggle your fingers under the wires.


Sommerfledt is expensive but they make catenary and pantographs. The problem with that dealer is the minimum order.




Viessman also offers N scale catenary.





An Eastpenn.org tuturial that includes building N scale catenary.



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I saw you were talking about this stuff in 07 on zeallot, which I know you are informed more so that I and you bring up a very good point that we all need to keep in mind.


Installing an extensive network of catenaries will require near perfect track work and should be done as the final step. If not then you leave yourself open for a lot of frustrations. The best solution is to plan access point to maneuver around and design a wired network that will suit your needs.


As you stated cost plays a big part in this endeavor but the attempt is to achieve a balance in cost, effort and aesthetic. If we can achieve that then its time well spent. 


From the links you posted it looks like music/piano wire is what these companies are using for the most part and .005 or 36 AGW is the magic number.


It seems like most of the guys here are using Kato or Tomix which sells their own simulated catenaries. These pieces are just a snap in unit. The void that I’m exploring is the wiring aspect for these pieces, particularly Kato because that’s what I have access to. 


The other factor that makes things easier for us, is our catenaries are non functional. This gives us the luxury of placing them where ever it looks nice so we can manage our layout in regards to placement.


I you see me going off on a tangent feel free to stop me.



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I have all the cantenary poles my layout has been removed to make way for the test configrations


I'm looking for a local wire supplier as I type. Hopefully I'll have the wire today.


I think I found the real solution.



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Martijn Meerts

I've built my own (functional) N-scale catenary before, long time ago, must've been about 15 years. I used a Sommerfeldt mast and some Sommerfeldt wires as a basis. Back then, Sommerfeldt wires were some sort of hardened copper wire.


Sommerfeldt catenary looks incredibly good btw, they spend a lot of time and resources in making sure it looks correct. Most Viessmann catenary is actually made by Sommerfeldt, same goes for the newer Marklin catenary.


Getting to the track when catenary is installed is obviously a bit more difficult, but it's not really that bad overall, and a layout with catenary looks much better than one without ;)

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Got the wire today and started working on the test model and ran into some issues. The Kato catenarys are flexing too much. In the prototype environment the temper of the cable is not and drastic as in the scaled environment. The actual temper of the cable/wire should be close to a wet noodle. 


This is not a major problem but hinders the progress. Because of the flexing more attention has to be placed on establishing the wire length and this takes too much time in the installation process.


I have a few option but it need to evaluate which makes more sense. I think I know whats best but it going to take a lot more time! :(



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On the subject of Catenary poles what material are most of them made out of? I need to know this so I'm painting them the right color.

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On the subject of Catenary poles what material are most of them made out of? I need to know this so I'm painting them the right color.


Some of the newer types appear to be concrete and other looks like galvanized steel of some sort. In any case gray or variant of gray would work.



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After doing some more research I found the best wire for the catenary wiring. It properties are pretty close but it has two strikes against it.


1 is the cost $0.31 a foot and

2. it is labor intensive.


On most catenary, runs can number up to 7 which equates to 7x 0.31 or 2.17 per track which started to hit the cost marker also the labor involved in hanging it. Strike 2


After thinking about everything I reverted to the  KISS rule.


Keep It Simple Stupid (KISS).


With that I asked myself what it the simplest way to achieve my objective.


I thought about it and thread ended up being the answer.


I bought a spool of thread, fabric glue and a burnishing tool.


This is what I came up in 5 minutes


[smg id=632]


There is something I don't like. The dusty look but that can be remedied by using bonded nylon thread. This type of thread has a coating that should eliminate the frayed strands of fiber giving it a cable look


I got 1000 meters of thread, glue and a burnishing tool for $16.31. I don't think you can beat that price. On top of that it is easy to hang.


The burnishing tool [smg id=633] is used to apply the glue.


Dab a small drop of glue on the tip, place the thread against or wrap it around the insulator and apply the glue. Wait a few minutes and its on. The ball tip acts like a soldering iron.I may switch

to super glue but I want to check it with the nylon thread before I recommend it.


To wire your whole layout with the main wiring (minus contact wire) for $16.00 isn't bad. I think using different shades or colors of wire may give it more depth. So adding a few colors for a few dollars seems



I'm going to setup a final mock up and lets discuss it. Two types of nylon thread in two colors


It may take me a day or so.



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We use elastic rubber 'wires'



Kia - I like the results.

        New problem, I just tried painting the Kato Catenary poles gray to give them that "weathered" look. The plastic that Kato uses is very durable but the paint doesn't adhere to it. Any suggestions?

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We use elastic rubber 'wires'




How do you attach them? Is it easy to make the dropper wires that hang the contact line from the messenger line?



       New problem, I just tried painting the Kato Catenary poles gray to give them that "weathered" look. The plastic that Kato uses is very durable but the paint doesn't adhere to it. Any suggestions?


This is a problem with a lot of plastics. First, wash them: They may still have a thin layer of mold release on them. Once clean (dish soap works), if paint still doesn't stick, you may need to use a spray primer—not just plain old spray paint, but a specific primer (and one that doesn't eat plastics!)

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Martijn Meerts

some lukewarm water with a drop of dish soap tends to help a lot. As for primer, Tamiya has some good primer spray cans for a reasonable price, they even had a grey one.


It also depends a bit on the paint, too thin or too thick and you might already have a problem. Tamiya paints for example tend to be too thick and are already half dried while still on the brush, which makes it difficult to paint ;)

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Martijn - I'm using Badger paint. I have 3 different shades of gray. I might experiment and rough them up with fine sand paper, what do you think?

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