Droop

I can't speak to a modeling choice.. but whenever I see pictures of a model railroad that has taught lines between the poles I find it somewhat jarring.

Chris

Now if you go back 50-100

Now if you go back 50-100 years ago, you WILL find the lines being very taunt....its an interesting thought.

Just a thought.  Make a half

Just a thought.  Make a half moon form, shallow. Cover it with something that glue will  not stick too. Put thin thread so it takes the curve.  Wet it down with water/glue mix. Let dry.

Now the fun part. glue the thread to the pole.   Other idea is glue thread to pole now setup the thread in your droop mold and mist with glue, let dry.

Someone try and let me know if I'm nut's...  Or I'll try it someday and find out

Marc

Benny, You beat me to it, I

Benny,

You beat me to it, I was going to say the same thing. I model the 1920's so all of the lines on telegraph poles would be very well maintained and be tight as a guitar string. Possibly some droop in places but very little as the photos of that era would suggest.

Interesting..

Interesting.. so what looks natural to me is a relatively recent thing?

I wonder if there is a difference in how telegraph wire was strung vs phone line and power, and what era would be appropriate to have the taught lines.

Chris

I recall the SP Siskiyou Line

The SP Siskiyou Line of the 1960s I remember as a kid had tight, straight wires on the telegraph poles. No sags.

So straight and taunt for the lines is prototypical as well ...

Straight wires would require

Straight wires would require tremendous tension to over come the tendency of gravity to make 'em sag. This had to lead to other problems with the strength of phone poles and arms and insulators - especially when the wires had to "curve".  So what was it that would prompt the users of the wires to put that much tension on them?

Charlie

I would think that it was a

I would think that it was a matter of physics and engineering for speeds upwards of 60 mph, give or take 10 mph?   The pantograph or whatever that ran along the wires would require a certain consistency of contact for proper transmission of power, and wavy, drooping catenary wire would impart a lot of by gosh and by golly to the equation, not to mention wear and tear on any tension devices built into the pantograph.  With a tensioned wire, the pantograph would not have to rise and dip, compressing and decompressing the tension devices unduly, nor wearing hinges. So I think, but perhaps there is another reason I am unware of.

-Crandell

Catnary

Catenary wires usually (iirc) had a carrier wire above that did drop and the pickup wire below that was attached to the carrier wire in enough places so it didn't droop. Sort of like a suspension bridge - the main wires droop like crazy although the bridge deck suspended from them was (more or less) level.

However, I was asking about telephone and power wires, not overhead wires for electric locos.

Regards,

Charlie

Modeling...

Berkshire Junction

I think is the name of the company in New England the makes the elastic wire for phone poles. BTW - I cam scratchbuilding all my poles. Will have shots soon.

In some of the older pictures

In some of the older pictures of places like NYC you see poles with upward to 20 stands on each stringer and then three or four [or more] stringers per pole.

That's a Lot of wire.

Now if you could stretch the wire taut, think about how much wire you could save over a long strech of space.

That's my thought - and the other part about the dropping lines starting to cause problems being close to other lines, while a taut line cannot come in close contact with anythign around it.

Taught wires

Like everything else that ages, wire tends to stretch. The older it is, the more it will stretch and that is why wire gets replaced every so often. Why? it will eventually break and it will create problems at that point. So it's often cheaper and better to do it before that happens.

More wire is made of other materials than what was traditionally used for the purpose these days. The wire needs less maintenance and it doesn't have to be replaced as often.

Irv

Perhaps it is whether cable or wire is used?

The reason that communication wires used to be tight and under tension could be that they were generally single conductors, hence the many wires per pole.  Now multi-conductor cables are used, and since they weigh much more they would tend to sag more.

Expansion and contraction due to temperature could also play a role in this.  If you look at high tension lines in the summer they will have a large sag in them; however in winter the wires will sag much less.

Selector

Good to have you over here. I bailed on MRF months ago. I do check the WPF's every weekend. It's cool to have some of the MRF folks come over and do both (if need be). I was really not learning anything there, so I went to http://www.therailwire.net which is real good and then found out from Bernie there about this site.

SP now UP here in the SJ Valley

The lines are so old, some areas have new poles and some new lines, other droop and have poles bent and supported by other poles and braces. I guess it depends on the area being modeled.

One thing I have done

In regards to telephone lines, I have in the past taken black tread and run it through a hardened bar of Caranuba Wax, it does two things, gives the tread a "memory" (for the droop) and secondly extends the life of the tread by insulating the fibers. One negative thing however is that it does collect dust but untreated tread will as well...

Mike

Bee's Wax and thread

I have always coated thread used as rigging on sailing ships with bee's wax. THis preserves to thread and it hasn't been a dust magnet either. But then I haven't built a sailing ship in a while now.

Irv

We have at least a few wires droop---

Even on some high voltage towers up here---some of the droop seen is built in to take up enough slack so if winds do blow you are not going to hear all kinds of reed effects--whistles,' moaning minnies ', and the like. They also droop because in some cases too taught a wire will snap and whipsaw about----or so I'm told by people who work in it---

Me? I'll keep drooping right along---my rural powerlines just seem to go with what I see out here----

Bee's Wax, Poles and Droop

Irv said:

"I have always coated thread used as rigging on sailing ships with bee's wax. THis preserves to thread and it hasn't been a dust magnet either."

Micromark claims that is a feature of using bee's wax on the rigging.  The thread will not collect dust.  It also keeps the thread from looking fuzzy.

In my opinion...if you are going to have poles they must have wires.

Everytime I see a layout with "naked" poles on it I have to shake my head.  No matter how good your poles might look they look out of place without lines.  The only time poles look ok without wires is where a new line is being run, IMO.

At the same time lines without any droop look fake too.

The guy that figures out realistic looking poles with drooping wires that can take a little rough handling while re-railing or cleaning, is going to be a popular guy!

I guess it's nice having a

I guess it's nice having a father who is a professional beekeeper...

Bee keeper?

Benny,

No beekeepers in my family, sorry.  All my Bee's wax would come from an online source.

Bee's Wax