Catenary on your layouts

Catenary on a layout does look nice, and many electric engines have an internal switch to allow them to use live pantographs and pick up the juice from a live catenary. I have also heard that if something goes wrong, entire lengths of catenary can be ripped down. Lots of work to get it back to normal.

I also remember reading about catenary that is not alive. In fact the wire is elastic, rubber, and should the pantograph grab it, it will stretch and not tear. Always looks good, but is electrically dead. So, there are several choices available and options that can be taken.

pennsy wrote:Catenary on a layout does look nice, and many electric engines have an internal switch to allow them to use live pantographs and pick up the juice from a live catenary. I have also heard that if something goes wrong, entire lengths of catenary can be ripped down. Lots of work to get it back to normal.

I also remember reading about catenary that is not alive. In fact the wire is elastic, rubber, and should the pantograph grab it, it will stretch and not tear. Always looks good, but is electrically dead. So, there are several choices available and options that can be taken.

This is why all metal construction is important. If you want to energize it, the option is available. A good solder connection will hold the catenary together, and it will be so sturdy you're far more likely to damage your pantographs then the catenary itself. Its not to hard to resolder things back into position either, as long as your iron is hot enough.

DO NOT USE ELASTIC/RUBBER. This is a bad idea. It does not always look good. In fact, it looks hideous, for several reasons. It will not hold a curve like steal wire (as in, you'll have to keep making lengths of straight sections on the curves), You cannot get it to form like steal wire, its not a smooth material, your pantographs will very likely get busted by catching on it, there is no good way to hang the elastic, it will get pushed out of shape by the force of the pantographs pushing up, it doesn't look right.

Using steel wire is superior, because its always smooth (or you can always go back and smooth it out with a file if you have to), its easier to hang, and it will hold a shape. If you do heavy catenary that has an auxilary (a secondary parrallel wire above the contact wire, not to be confused with the arch in support wires), you have a garunteed steady and smooth piece of catenary wire to hang. You can solder sections together between the wires, and hang the wire by the auxillary so that you have less interference on the contact surface of the wire. It also holds the catenary much more vertically stable, so the pans won't be able to push the wire up. You can easily make curves that match yours smoothly.

green_elite_cab wrote: Using steel wire is superior

Based on my experiences i urgently recommend the use of hard copper wires if anybody want to use the electrical function of a catenary. Otherwise you could get oxidation troubles in the future; stainless steel would be the best option but unfortunately it´s impossible to solder.

Petz wrote:

green_elite_cab wrote: Using steel wire is superior

Based on my experiences i urgently recommend the use of hard copper wires if anybody want to use the electrical function of a catenary. Otherwise you could get oxidation troubles in the future; stainless steel would be the best option but unfortunately it´s impossible to solder.

hard copper wire? Sounds interesting, i'll have to look for that. does it match the steel wire in strenght? I suppose even it it doesn't, if i solder the steel wire to it so that its two layers like my other catenary wires, then it will hold steady.

Considering the present price of copper you may just want to pass on that one.

I don't think I would worry that much about the price of copper. I mean, unless you have some massive layout, we're probably only talking a couple pounds of it, at most.

Phosphor bronze has always been popular for overhead wires (as well as pickup wipers on the wheels of many model locomotives). It's stiffer than copper of a given size, which means you can use a smaller diameter that looks better. It solders well and shouldn't suffer the oxidation problems that some materials might.

For the above reason, I do NOT recommend using steel wire - plain and simple, steel rusts. I don't know if there are any chemical blackeners that would form a protective coating on steel, but I would definitely avoid it. I had left a piece of .020" steel music wire lying near my work area for several years, and it's totally caked in rust now. Another potential problem with steel is that it's a harder material than what your pantograph sliders are probably made of, so it may cause extra wear and tear on them over time.

Another possibility might be nickel silver. I can't remember if I've heard of this being used for overhead wires, but obviously it's worked out well for rails! It might be harder to find, but I'm sure you can get a spool of it somewhere. In fact, try here: http://www.smallparts.com/

Oh, and just to clarify - stainless steel can be soldered, it's just a lot more difficult than other metals and it often requires a certain type of solder. That's probably what Petz meant by "impossible," not that it can't be done.

astrosa wrote:I don't think I would worry that much about the price of copper. I mean, unless you have some massive layout, we're probably only talking a couple pounds of it, at most.

Phosphor bronze has always been popular for overhead wires (as well as pickup wipers on the wheels of many model locomotives). It's stiffer than copper of a given size, which means you can use a smaller diameter that looks better. It solders well and shouldn't suffer the oxidation problems that some materials might.

For the above reason, I do NOT recommend using steel wire - plain and simple, steel rusts. I don't know if there are any chemical blackeners that would form a protective coating on steel, but I would definitely avoid it. I had left a piece of .020" steel music wire lying near my work area for several years, and it's totally caked in rust now. Another potential problem with steel is that it's a harder material than what your pantograph sliders are probably made of, so it may cause extra wear and tear on them over time.

Another possibility might be nickel silver. I can't remember if I've heard of this being used for overhead wires, but obviously it's worked out well for rails! It might be harder to find, but I'm sure you can get a spool of it somewhere. In fact, try here: http://www.smallparts.com/

Oh, and just to clarify - stainless steel can be soldered, it's just a lot more difficult than other metals and it often requires a certain type of solder. That's probably what Petz meant by "impossible," not that it can't be done.

Yeah, i have only a small 4x8, i'm not going to be using much.

I've seen the phosphur bronze stuff, but i worry if it is to thin for some applications, but i suppose i should buy some first and see what happens. I've had some some supposedly steel music wire i've been using for 5 years now and it doesn't rust. the worst i've seen happen to it is it gets like a blackish oxidation, but so far it has been nothing so serious that I can't clean it off easily. I personally plan to paint my wires (I don't want to power them), so i'm hoping i can seal the majority of the system in.

then again, when i bought this original wire that i've made into my actual contact wire, i was told it was used also on model aircraft for controls and such, so maybe it isn't steel wire he gave me. In fact, now that you mention it, i'm wondering if it is actually steel. I know the majority of the wire i have now is from K&S engineering, and it doesn't seem phased at all, ( i have some still sealed in the packaging for a couple years now. i do have on small piece of wire that has some rust, but it seems different somehow.

I personally though would avoid spooled wire in this case. If it's on a spool, chances are it is still to soft. I can imagine it being very "coily", or it would be to soft. We want our catenary to be relatively straight. I suppose when you solder it all down it will be held right, but i'd rather it be straight from the start.

I'm not sure what you mean about phosphor bronze being too thin. If you want thicker wire, buy a larger diameter!

To find out whether the wire is steel, try waving a magnet near it. It's possible that it may be steel but with a protective oxide coating, in which case (as you seem to have found) it may hold up just fine. I'm not sure if the available chemical weathering solutions (i.e. A-West's Blacken-It, Patina-It, etc.) actually provide a protective oxide, but that could be an alternative to painting that would still allow the wires to conduct.

Good point about pre-straightened wire. The site I mentioned does sell certain types of wire in straight lengths, but not all.

astrosa wrote:I'm not sure what you mean about phosphor bronze being too thin. If you want thicker wire, buy a larger diameter!

To find out whether the wire is steel, try waving a magnet near it. It's possible that it may be steel but with a protective oxide coating, in which case (as you seem to have found) it may hold up just fine. I'm not sure if the available chemical weathering solutions (i.e. A-West's Blacken-It, Patina-It, etc.) actually provide a protective oxide, but that could be an alternative to painting that would still allow the wires to conduct.

Good point about pre-straightened wire. The site I mentioned does sell certain types of wire in straight lengths, but not all.

This is true... I'm assuming this is some tough stuff as well? I was about to get more wire ( i didn't have enough of the original stuff to really do much work), so if this phophur bronze is easier to solder and looks better, i'll take that. I just hope it is as sturdy as the wire i have, which is pretty good. I suppose Model Memories has been making their catenary wire out of this stuff, so it must be fairly reliable.

What i have i definitely steel wire, it sticks righ to the magnet. Still, i can't really find rust on it, so i'm guessing you are right in your figuring that it has protective coating.

I personally intended to paint my catenry because its purely going to be for show. I'm not sure i'd want to run all catenary because then other models would workon the rails. I might try it one day, but not on my layout.

Well, i've went a head and built one segment of catenary. rather than build a bridge, which has turned out to not be as sturdy as i hoped, i built two catenary poles with a wire cross span, which is hooked into the poles (made of code 100 rail, close enough!). It has turned out to be very sturdy. I tested it with my Acela dummy locomotive, and the pantographs didn't catch anywhere yet, so i'm confident that I have a nice smooth surface to slide over. I really think the only adjustments i need to make is to make the wire more centered over the rails, as i built one rail a little bit to far off the side (the pans stayed under it, but it was to extreme for me to write it off as staggering the contact wire as is prototype practice). That shouldn't be to difficult to fix though.

the whole thing is soldered together, and i just ned to add the details to it.

How about pantograph wear? Someone told me they had a problem with wearing a rut in the pantograph shoe from the wire, and replacement parts had become a problem, not to mention the headaches that come with disassembly/reinstallation.

He tried not fully extending the arm, so that the pantograph wasn't making contact, but after all the time, effort and $$$ he put into his railway, it wasn't the look he was shooting for. He got the idea to cut small, narrow pieces from clear plastic straws and glue them to the shoes. I don't remember what he used for glue. The arms were fully extended but the plastic from the straw made contact with the wire and protected the metal pantograph from wear.

D/

green_elite_cab wrote:Well, i've went a head and built one segment of catenary. rather than build a bridge, which has turned out to not be as sturdy as i hoped, i built two catenary poles with a wire cross span, which is hooked into the poles (made of code 100 rail, close enough!).

You know, you don't have to guess... there's all sorts of books and magazine articles that tell you how to build your own working catenary...

Dieter wrote:How about pantograph wear? Someone told me they had a problem with wearing a rut in the pantograph shoe from the wire, and replacement parts had become a problem, not to mention the headaches that come with disassembly/reinstallation.

He tried not fully extending the arm, so that the pantograph wasn't making contact, but after all the time, effort and $$$ he put into his railway, it wasn't the look he was shooting for. He got the idea to cut small, narrow pieces from clear plastic straws and glue them to the shoes. I don't remember what he used for glue. The arms were fully extended but the plastic from the straw made contact with the wire and protected the metal pantograph from wear.

D/

Thats interesting. I didn't think that would happen so much on the model. even then, thats what wire staggering is for, lol. I'll definitely keep that in mind though, because that is a creative solution to a problem i had not anticpated would affect my models.

Otto Vondrak wrote: You know, you don't have to guess... there's all sorts of books and magazine articles that tell you how to build your own working catenary...

If you can find them, then please, link them! I have found very little on the modeling or North American Catenary. While there is plenty out there on traction catenary for trolleys, good luck finding stuff about modeling a Heavy Electric line.

I have found two articles on PRR style catenary, One for the Milwaukee Road, and one i found particularly creative for modeling New Haven lattice catenary bridges (used clear plastic square rods and attached the lattice around it).

The main articles i'm taking from are Bill Kachel's pennsy catenary, which is pretty basic and easy to do. I think on the same site that hosts this article, they have "Keystone modeler" newsletters, which focuses on the PRR. They had an excellent three part series on scratchbuilding RIDICULOUSLY detailed PRR catenary like that over the Northeast Corridor. I can't find the links, but i have the PDFs if anyone wants them.

The only problem with that last article was that in the end, the costs of building that catenary were rougly above the costs of buying the Model Memories PRR/NEC catenary kits (though not by much).

Perhaps if the special H-columns were more readily available, i wouldn't have minded trying to build it this way one at a time, but already had lots of code 100 rail i had originally bought for this purpose (at the time, i had only seen Bill Kachel's article, which said to use brazing rods, which are round. Rail is about the same with but "square", and so it better fit the job.


anyways, i'm going to see if i can't build jig to assist in making the cross spans, and maybe i'll post my measurements here when i get it all finalized. I would take pictures, but i still haven't gotten my camera to work.

Has anyone attempted a trolley pickup with a real wheel on the end like the real thing? Thinking about shoe/arm wear, a wheel would last a lot longer.

D/

Dieter wrote:Has anyone attempted a trolley pickup with a real wheel on the end like the real thing? Thinking about shoe/arm wear, a wheel would last a lot longer.

Not enough mass for a tiny trolley pulley wheel to spin freely... would just end up being dragged along the wire due to the friction in the axle.

-otto-