Home made catenary

[Vecchio]

Working catenary home made - possible?
 
This article describes a catenary system following the Austrian design, but I am sure with a bit of fantasy it can be also transferred to every other country as long as there are simple pole designs in use (For example Netherlands – I shaped steel girder or round concrete poles, Italy – round steel poles, Norway-I shaped steel girder poles, Rumania – round concrete poles) or of course the UK. Just go out and see how the real thing looks and have a go at it!
I made the experience that it is not too difficult to make a catenary system yourself, and besides the financial savings it was a lot of fun for me to do it.
 
First I would like to present you the manufacturing of catenary wires and concrete poles – latter in 2 different versions.
 
Catenary wire. The material used by me is zinc coated mild steel wire, a material you can find in the garden department of several DIY markets. It is important that the wire has a smooth surface and allows some elongation. Now about the diameter. The Industrial standard is now between 0,5 and 0,7mm. As my catenary wire will be soft soldered I decided to use 0,7mm.
 
About the necessary tools:
A set of side cutting pliers of good quality (has to be hard enough to cut the steel wire but sharp enough to allow clean cuts)
A pair of tweezers – if possible from metal but non magnetic
A soldering iron with a fine tip but not too weak, for instance 25 Watt.
A device to hold the wire pieces in position – not a must but it helps a lot.
Flux – without flux it is not easy to solder the zinc coated wires. I use a zinc-chloride based type.
Soldering tin– good quality for electronics – diameter 0,5mm if possible.
 
For the catenary wire we need to make a soldering stencil first. If you want to make only a few meters this can be made with a piece of ply wood, minimal thickness 10mm (because we have to nail in some nails) If you want to start production in a more “industrial” style it could be a scrap piece of furniture board or kitchen top. They are normally coated with FRP which is more resistant against the flux and the high temperatures of the soldering iron.
 
Draw the shape of the catenary wire on to the surface of the board you have chosen before. Nail steel nails without heads into the board in a way that they will fix the position of the steel wire. Leave enough space for the wire diameter to avoid bending it (See picture). It makes sense to prepare a piece of steel wire before this task to check the position of the nails. The suspension wire (the upper wire of the catenary system) follows approximately the shape of a parabolic curve. Therefore the wire has to change its direction a little at every cross wire. Put a nail into every crossing point. When you put the suspension wire into the stencil you have to bend it in a way that it follows the shape of the stencil without any remaining tension. (if there is remaining tension the whole thing will warp when you take it out of the stencil.
c1 by Gerhard Novak
 
To straighten the steel wire put one end into a stable and well fixed vice and pull on the other end with strong flat pliers. Close the pliers firm so that the wire does not slip out while you are pulling. Try it with a length of approximately 60 cm first.
Attention – the steel wire will start with some plastic elongation (for a soft wire approximately 15 to 20% ) and if you increase the force it will break. Try to elongate but not to break the steel wire. Keep in mind that the wire may break at any time during this procedure. A little scratch or impurity can be enough to start this. There is the danger that you can hurt yourself, especially if there are some objects or even a wall behind you …. After this procedure you will see that every bend that was in the wire before has disappeared and it is totally straight. Also it is a little harder now as it was before. Try to open the vice or cut the wire from there without bending it. We need straight wire pieces for the following steps of production.
 
After the wires are in position in the stencil we have to make the cross wires. Use a scrap piece of straightened wire and cut off the required length with the side cutting pliers. May be you have to try it several times until you get the right length.
 
The cross wire has to be moved into the right position and held in place during the soldering. Moisten the connection area with a very small quantity of flux and solder the connection by using only very little tin. Try not to solder the wires onto the nails of the stencil. If flux comes onto the nails this could easily happen.
 
. by Gerhard Novak

 

Proceed in the same way with all connections. If everything worked you can lift the first piece of catenary wire out of the stencil.

 

. by Gerhard Novak

 

If the tin did flow properly at the connections they are quite rigid. It is very important at this point to remove the residues of the flux. To do this wash the finished catenary wire carefully with a little bit of washing up liquid. You can treat the connections also with a soft brush (old tooth brush)  during washing. If you do not remove the flux the connection area will be black within a few days.

 

The first part of the work is finished now. You have produced a stable but on the other hand also a fragile catenary wire. Length and shape you can change to your needs by creating the necessary stencils.

 

Concrete pole

 

The catenary wire alone does not help us – now we need poles. In Austria most of the poles are made from concrete.

 

The standard poles of OeBB have at the base a profile of approximately 200 x 325 mm and at the top 200 x 200 mm. If we translate that into our model world these are 2,3 x 3,7 mm. The height depends on the standard for H0 models and on the track height (brand dependent) you are using. (see drawing)

 

Simple Version:

 

For the simple version I use square shaped hard wood profiles of 5x5mm. These are ground to a slightly conic shape with abrasive paper. For this work an electric grinder for wood is of great help.

At the foot of the mast a hole of 3mm diameter has to be drilled. This work is a bit delicate because only 1mm of wall thickness will remain. Who owns a lathe with a four-jaw chuck should use it for this work.

Into this bore a 3mm threaded stud will be glued. The length has to be calculated – it is the thickness of your baseboard + 15mm. As glue use a slow setting araldite resin type (for instance UHU plus endfest 300). At this point we need high mechanical strength.

 

For the installation of the bracket two holes of 0,8mm diameter have to be drilled into the pole according to the drawing. The height of the pole depends on the top level of your track and on the standardised „Normal level for H0 catenary wires” according to NEM 201. NEM 201 asks for 69mm above top level of the track. It is useful to get a copy of the NEM standard because also other important information like the biggest side deviation of the catenary from the track centre and more can be found there. The standards are available in the internet – look at http://www.morop.org/en/idf/index.html. (The website is available also in English but the standards only in German and French) 

 

c4 by Gerhard Novak

 

The basic pole is now ready – what we need now is a catenary arm.

 

The target was to find a robust design which looks neat. After a few  negative trials I found the following form: As material I use spring steel wire of 0,8mm diameter – this for sure to thick for a scale version, but the catenary should also be operational.

 

On one point of the bracket a connection of 2 wire pieces is necessary – this is the biggest problem of the design. I use an “insulator” made from brass which has also a function as a splicing sleeve for the 2 steel wires. Both steel wires are flattened at the zone of the connection by the use of a fine grinder. The insulator is holding both wires in position and the connection is fixed with soft solder.

 

c5 by Gerhard Novak

 

For all who cannot make their own brass „insulators“: If the 2 steel wires are wrapped in the connection area with a fine copper wire and this connection is also soft soldered with the help of some flux it will also give a good mechanical connection. To improve the look dummy insulators made from plastic which are available in good model shops can be applied.

The ends of the bracket which will hold later the catenary wire have to be tin coated to make the soldering of the catenary wires easier when the pole is in its final position.

The bracket has to be washed (as before the catenary wire) to remove the remaining flux. After that the bracket has to be glued into the 0,8mm holes of the pole by using cyano acrylate glue. Finally pole and bracket have to be painted and can be used now.

 

Who wants to improve the look of the pole can also make the fittings which hold the bracket. I used small plastic profiles for this job.

 

I have approximately 50 pieces of this pole type in use on my layout and I am satisfied with the look and the functionality. But do not put any scale people to close to the masts – because then everybody will notice that the poles are oversized.

 

Concrete pole – improved version

 

We should never be satisfied with our results – therefore an improved version. Also this pole is not to scale, but already much closer. If we want to go to the scale size of the poles the use of wood will be difficult fort two reasons.

1) the wood gets very elastic at this thickness

2) there is no possibility to fix a threaded stud to the wood – not even if we use M2. Therefore we need to change or design to brass. I use a profile of 2,5 x 3,5 mm. The design is similar as before, new is the additional base of the pole which makes the use of an M3 stud possible. A lathe helps during the production but it is also possible to make it without.

 

The pole will be connected with the base by the help of an M3 thread (this works only with a lathe) or it will be connected by soldering, to get a stable connection it is necessary to file a gap which corresponds to the width of the pole into the base. I tried both, the method with the thread is more stable and easier to handle.

 

c6 by Gerhard Novak

 

At the moment I use the same bracket for this pole. For sure also this is a field for improvements

 

For problematic situations, where it is not possible to access the threaded stud from below (for instance at hidden underground sidings) a base plate can be added which allows to fix the pole with two screws from the top.

 

On the rather slim pole the fittings we I have used on the wooden version look a bit too big. If possible we should use smaller brass profiles instead.

 

Installation

 

Try to find the right position of the poles – which can be tricky sometimes because of point motors, construction wood or in my case because of the catenary system in the area of the hidden sidings below the baseboard.

You can position the poles by following the rules of the standard mentioned before (biggest distance of wire from the track centre) or using the “empiric” method using an engine to find the right position. For my experience the best is to use a short engine with a central trolley (I use a Roco 1161, here even the contact piece is rather narrow in comparison with modern Austrian engines). If this engine has a secure contact to the wire every other engine will pass.

The poles are fixed by threaded studs with a nut from below the baseboard.

Then a matching piece of catenary wire has to be soldered to it. I bend the ends of the contact wire with some small round pliers into a small u so that they fit to the bracket. The top wire I just solder without bending to the bracket and cut away the end of the wire. This method almost guarantees that there is no tension on the top wire – which would lead in a bended section of catenary. Only at section breaks between modules where I have to remove the catenary before storing the modules away I make the u bend also at the top wire. At this point I do not solder so the u-shaped eye has to hold the catenary.

 

Have a look at a few pictures of the catenary system.

 

c7 by Gerhard Novak

 

c8 by Gerhard Novak

 

c10 by Gerhard Novak

 

​Enough for now, a little bit more later...

[Joseph_Pestell]

Cracking work! I had a friend in France who made his own. He was a professional solderer (repairing radiators mainly) but I don't think his catenary was as good as yours.

[Vecchio]

Thanks Joseph. I learned soldering and welding during my education, that helps. But everybody can learn it. Just needs a bit of practice and the right materials.

 

There are a few more photos coming... If you look at the dates of the drawing it is more than 10 years that I did this work. The layout is part sold - part given at a present to the local club. I had a 6 years break - but I have just recently purchased some brass profiles to repeat the exercise....

 

And by the way - this catenary was good enough to go with pantograph up during shows. Probably I find somewhere an old video...

[Vecchio]

Just to show the catenary is operational - a short clip from trenini in mostra 2006 - Carnate - Italy. Dring during the show with pantographs up. Just click on the picture to open the link.

 

carnate_austriaco_02 by Gerhard Novak

 

and another one..

carnate_austriaco_01 by Gerhard Novak

Edited July 27, 2016 by Vecchio

[Vecchio]

No disrespect to your work, but for many European overhead systems, Sommerfeldt makes suitable parts for not too many modelling tokens. That includes the UK (initiated by Peco) Yes, it does involve compromises on a number of parts, but all for operational usability.

 

Agreed, making it myself makes more fun...

For me it is fun in the making not only in having it.

[Vecchio]

After mastering the standard stuff it was time to go a little further...

 

And of course you can do more. Have a look at the lines and copy what you need. For instance in some situations there is no space for a pole – you need two brackets supported by one mast

 

c11 by Gerhard Novak

 

Or a wire tensioning system.

​First the idea

 

c12 by Gerhard Novak

 

Then the production

c13 by Gerhard Novak

 

A partial assembly

 

c14 by Gerhard Novak

 

And finally the whole thing.

 

c15 by Gerhard Novak

 

Or even more. A station switchgear. Lets have a look at the real thing first. Station Klamm am Semmering, probably 2004

 

c16 by Gerhard Novak

 

And now on my model.

c17 by Gerhard Novak

 

As I modelled also the border to Italy - we find also their system. Now 3kV DC. Different masts, different insulators.

cIT1 by Gerhard Novak

 

cIT2 by Gerhard Novak

 

At the border station - changeover from one system to the other one. On the road the old custom building, now, with Schengen no longer in use.

cIT3 by Gerhard Novak

 

cIT4 by Gerhard Novak.

 

​Hope you enjoyed that. If anybody is interested on a copy of the drawings just let me know.

[Gordon H]

The suspension wire (the upper wire of the catenary system) follows approximately the shape of a parabolic curve.

 

 

On a slightly pedantic note, a few things ought to be clarified:

1) The curve the 'suspension' wire forms is a hyperbola, not a parabola.

2) As such, the hyperbolic wire is known as the catenary wire.

3) What you have referred to as the catenary wire is usually known as the 'contact' wire.

 

However, it is good to see someone else doing it themselves and encouraging others to have a go. I have been doing the same for over 30 years - though I take it a stage further and insist the system conducts too.

I wish I could show you a video of our club layout 'High Gill' working this way on a BBC TV programme 29 years ago, but it's not my copyright.

[Vecchio]

Gordon,

 

many thanks for your correction, the professor who taught me geometry is for sure long gone from this earth so he cannot tell me off for this mistake. Also the community will see that I sometimes make mistakes, as English is not my mother language. Would like to see others writing in foreign languages.

 

About the copy rights - I am not too sure if the little videos I showed are under copyright or not as they have been made by a local television company (of course in a better quality) and have been broadcasted in the north of Italy in 2006.

 

I wouldn't be a problem to use the wires also as a conductor for the train - as I used DCC it was not necessary to do so.

[Horsetan]

.... it is fun in the making not only in having it.

This motto should be framed and hung on every modeller's wall.

[roythebus]

I was in charge of the Model Railway Club's "New Annington" layout in the 1980's; that was fitted with catenary. On there we used a mixture of home-made masts and cross wires and commercially available catenary wires and insulators. The whole thing worked quire reliably with pantographs up, though the wires were not electrically live. We had run-off ramps where the running lines went into the tunnels for the hidden sidings.

[Vecchio]

I didn't use ramps but had a functional catenary - or in this case rather contact wire in the tunnel. In the hidden part of the large module (complete circle with sidings under the baseboard) I used the Kleinbahn catenary system - I swapped some H0e stuff with a friend and got all his Kleinbahn stuff including all the catenary system. This was punched from flat copper - very stable, not nice to see but ideal for the tunnel.

 

And in the picture below you see what was used in the return loop of my old lay-out. The black devices on top of the wooden cross bars next to the contact wire are not screws but photo cells to detect the train position. Why? You enter the tunnel - after that is a point and a hidden siding which allows you to change train in the tunnel. This works only when you know where you are. Today I would use a video camera as they went small and cheap, 10 years ago I made an array of photo cells and led's which displayed me the position of the train on the mimic board... And yes - I made also the electronics for that myself using integrated multi channel operational amplifiers....

 

The material for the contact wire was a brass tube of 2mm diameter, soldered to the head of metric screws which go through the wooden cross bars. Cost: almost nothing...

 

Fotozellen im Schattenbahnhof by Gerhard Novak

Edited July 29, 2016 by Vecchio

[Gordon H]

I was in charge of the Model Railway Club's "New Annington" layout in the 1980's; that was fitted with catenary. On there we used a mixture of home-made masts and cross wires and commercially available catenary wires and insulators. The whole thing worked quire reliably with pantographs up, though the wires were not electrically live.

 

Yes, I came to the MRC on a couple of occasions and showed Jon Hewitt and Brian Kirby how we had produced the headspans on 'High Gill', which had appeared at IMREX that year (1986). In those days we had the advantage of King's Cross models down the road who stocked all the brass sections needed. No doubt Brian got a discount, as I seem to recall him being one of their shop assistants. This discussion seems somewhat familiar, having cropped up a while ago in a different thread...

[Crewlisle]

Having had over 30 years experience of OLE on my 00 gauge exhibition layout ‘Crewlisle’, here are a few points to consider:

1.  Use whatever masts you like, but it is best to make your own catenary wires as they are unique to each layout.
2.  Be wary of using mild steel wire because it is very easily ‘bent’ if something drops on it or a pantograph slips & catches it.  Then you have the problem of straightening it out in situ.
3. My catenary & masts are all portable taking about 30 minutes to set up at exhibitions.  Catenary is made up to span on average four or five masts over various radius track, points, tunnels & baseboard joints inside the tunnels.  It is tested to 100 mph with the pantograph in contact with the wire.
4. I use 0.5mm high tensile steel piano wire.  I have had my Class 87 snag a wire at a scale 80 mph, bend it back about 60 degrees but it just sprung back to almost its original shape.
5. The wires are made up flat on a wooden batten then bent to provide a straight line between masts. 
6. Details of how it was all done appeared in February 2014 Model Rail magazine (except details of the catenary in tunnels & crossing baseboard joints inside the tunnels which were omitted due to lack of space!).  Also see photos & comments 9, 61, 64 & 88 in the ‘Peco’ Forum about ‘Peco announces OHLE'.

 

I didn't use ramps but had a functional catenary - or in this case rather contact wire in the tunnel. In the hidden part of the large module (complete circle with sidings under the baseboard) I used the Kleinbahn catenary system - I swapped some H0e stuff with a friend and got all his Kleinbahn stuff including all the catenary system. This was punched from flat copper - very stable, not nice to see but ideal for the tunnel.

 

And in the picture below you see what was used .............

 

n im Schattenbahnhof by Gerhard Novak

 

 

Vecchio's catenary in tunnels is over complicated, why not use a very simple method like soldering 1.5mm wire soldered to 25mm x 25mm brass/tinned steel plate secured with impact adhesive to overhead baseboard for the pantograph to clear any point wires, etc..?  See photo below which shows baseboard joint continuity & 1.5mm wire + plates  secured to high level baseboard.

 

[Vecchio]

I stop here with this thread - but if you would like to see how I make the poles and the OHL wiring have a look into Donnersbachkogel. It will not be a very fast thread - as I have to work and I am quite busy - but as 10 years have passed since my first OHL production I try to make it better than last time. (smaller wire diameter, only brass poles ....)

Thank for looking into this thread

 

Vecchio

[vulcan product fan]

super work pal looks very complicated 

[Vecchio]

Well - tried to make it as lifelike as possible. Look from time to time into Donnersbachkogel - this is the layout I am currently working on - here I make my own OHL wires as well - and of course improved (0.6mm contact wire, all other wires 0.5mm)

[Dazza2502]

Thank you Vecchio for your information about catenary!

 

I am working on my own and there is very little information about making your own catenary network.

 

Regards

 

Darren

[Vecchio]

Thanks, you can also see it (if the covid 19 virus allows it) - Donnersbachkogel will be on show at Railex NE 18., 19.7.2020 and then in May 2021 (probably more realistic) in Watford. 

[Re6/6]

I've only just come across your thread. Superbly informative.

 

It's a pity that I hadn't seen it before placing a quite large (and expensive!) order of Sommerfeldt from Modellbahnshop-lippe! Mind you 'Swiss cheese' spans would be very hard to make.

 

Good stuff though, thanks. 

[Vecchio]

There is always the question about reliability. The Sommerfeldt stuff is resistive welded. My system is soft soldered. So there is an advantage  point for Sommerfeldt. I have purchased a few length of Sommerfeldt catenary to understand the difference. Actually they are not much more firm than mine. Also the welding is on one side of the contact wire - why my soldering is on top of it. Sommerfeldt then cuts off the wire, which is normally fine, but in one case I found a piece of wire standing out and it would jam the pantograph if you would use it as it was.

Nothing bad about Sommerfeldt, nowadays I am using their copper clad steel wires for making the catenary as I do not find the Baekert wire any more I used in the past. Also the pantographs made by Sommerfeldt are very stable, I changed a whole range of locomotives (PIKO) over to Sommerfeldt as they look better and work better.  

[cravensdmufan]

Hi Vecchio,

 

Just found your topic - very interesting and potentially useful for me as I have had a good few masts in a box in my garage, so this has got me thinking about OHLE again - yet another project to consider during self isolation!

 

Thanks for posting.

[marhow105]

Has anyone decided the max catenary length on straight track that can be used before the pantograph  pushes the catenary upwards to an unacceptable extent? I realise that much depends on the upward pressure from the pantograph, but assume that it exerts only sufficient upward pressure to keep the pantograph in contact with the catenary.

[Vecchio]

This depends very much on the materials used - with 0.7mm I  went up to 400mm but not much more. The prototype would also see longer spans, but they are nicely tensioned. Something you cannot easily transfer into model scale. And - I don't remember if I wrote it further up in this thread - if there are 2 springs in your pantograph then take one out. Helps a lot.

[dmu 156]

I'm currently installing catenary on a layout for Pete Waterman that is to be exhibited at Chester Cathedral in July . There is a video on Youtube called 'Making Tracks' of the layout still under construction. The gantries are laser cut and the cantilever masts are Peco, the catenary wire is a mix of Sommerfeldt and Peco using the maximum lengths available

of 500mm and some 380mm lengths. The catenary wire is mainly 0.5mm diameter so is quite flexible and bends easily so I've incorporated automatic tensioning as is the case on the real thing at each end of each wire run and this keeps the wire taught, as the tensioning is automatic it compensates for temperature changes and keeps the mechanical loading on the registrations arms equal. At the time of the video being filmed the tensioning assemblies were not installed.

[dmu 156]

You can now see two tensioning assemblies installed on the 'Railnuts' facebook page. As the layout only has catenary on the scenic sections I've hidden some of the tensioning assemblies in tunnels.