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ChicagoNW
13th Mar 2014, 01:57 AM
As many of you know I kinda model the Chicago rail scene.

I try to model not just today but the past as well. Stuff like the freight trains, passenger trains and diesel commuter trains are pretty easy. Even doing the streetcars is not to hard when you learn how easy it is to hang overhead wire. Now granted the IC Electric Lines are a future project as the cars are really a unique mix of old and new. I wasn't really exposed to the North Shore Line, but there now is a static version of the Electroliner! They really are just an interurban lines, when all is said.

But this tread is about something that almost defines Chicago, The L. Many of you will want to put an E in front of the L but that stands for elevated trains. Those run in other cities. The L just doesn't hover over the streets and alleys of the City. It travels on the ground and can be found underground too.

http://www.nscale.net/forums/attachment.php?attachmentid=35858&d=1350674591

What makes the L different from the other forms of rail transportation is how it gets it's power. It doesn't carry fuel like a diesel or steamy. It doesn't usually get electrical power from an overhead wire, except the old Skokie Swift.

http://www.nscale.net/forums/attachment.php?attachmentid=5638&d=1276299303

It uses a third rail for power.
No one makes three rail track for transit lines.
56142

Now there are some ideas that were worked out in the early days of N-Cat. But I think that a better idea can be had. Here's what they came up with…

56143
As you see they came up with two good answers but the screws can get really tedious for more than a couple of feet of track. Not at all realistic. The plastic supports are a lot easier but don't work for every brand of track.

So what ideas can you come up with?

It should be simple
It should work for any brand of track
It should be easy to do for a dozen or more feet
It has to work on 103mm curves as well as larger ones
It should not destroy the regular track
It should not be too unrealistic
The places where it starts should be able to form a ramp in the third rail. See the above picture. The ramps are \ used at street and rail crossings as well as switches.
It has to be able to be placed on either side of the tracks
It has to be durable
It will be used for power - NO Plastic Dummies!


56144
That is a prototype gravity shoe, used by the CTA. It does not have any springs, hydraulics or pneumatics pressing it against the rail. It just hangs until it contacts the rail.

The N-Cat shoe is more like a phosphor-bronze curb feeler. Look carefully at the N-Cat picture and you will see it. Just like when O and HO used outside third rail.

I've got a different idea…
56140
I mounted a bracket on the upper car on the right hand truck…
56141

So, what ideas, can you, come up with?

MetroRedLn
13th Mar 2014, 02:29 AM
Third Rail pickup is common for heavy rail/subway operations. My handle's namesake also uses third rail.

To make it work you would need to make your own custom track gauge to make sure the third rail is at a consistent height and distance from the running track's centerline. I would buy some bulk rail that's at a smaller gauge than your running rails (Code 55 if you're using Code 80, Code 40 if you're using Code 55), and make brackets out of styrene to hold the rail at that level. Your pickup shoe should be able to slide along the top of the third rail at a constant height and distance, so having a spring would help (much like the prototype has). To power it, it's all a simple matter of disabling one of the running rails from DC power/DCC signal and use the 3rd rail to supplant it.

However, if you use turnouts in your L Train operation, that complicates matters somewhat. The 3rd rail doesn't have to shift like the running rail, but you need to have the 3rd rail on the other side of the track of the diverging rail to have your power needs covered, which means your pickup shoes have to be on both sides of the cars.

ChicagoNW
13th Mar 2014, 03:08 AM
Actually CTA shoes don't have any springs. Gravity does all the work. Because the shoes can skitter, snow and ice on the third rail makes lots of pretty blue sparks. The married pairs don't depend on a single shoe, there is little power lost.

When fully outfitted each married pair will have eight shoes, two per truck. Putting pickups everywhere lessens the chance of a stall at a gap in the 3rd rail. The more sets of cars the easier it is to cross a street.

MetroRedLn
13th Mar 2014, 05:10 AM
Actually CTA shoes don't have any springs. Gravity does all the work.


But you see, the laws of gravity are much different in 1:160 scale. 1:1 scale trains rest on their trucks which are held by gravity. Yet 1:160 trains need bolster pins or screws to hold the trucks on. When a slight kink or bend in your running rails cause your pickup shoe to lose power because it's being lifted by a hairline fraction of an inch, then you're gonna need a spring or some mechanism to keep the 3rd rail shoe's contact consistent.

Trentbradbury
13th Mar 2014, 08:50 AM
I would look to ho scale slot cars for pick up shoe parts especially springs. being a slot car guy as well as a train / traction nut I am sure there is something available that is adaptable. As far as the third rail goes have you considered solid copper wire? this may be helpful during the r/d stage as far as slot cars go the best custom routed tracks use continuous rail for the best performance. I'll be watching this closely to see what happens

Trent

Spuds
13th Mar 2014, 10:25 PM
I've heard of ho track that's combination narrow gauge and regular guage, since their narrow is our standard, the extra rail might be right spacing for you.

BaRT uses 3rd rail also, they raise it, cover it for some reason, and use paddles on sides of all cars.

PW&NJ
14th Mar 2014, 08:27 AM
Deep within this post:

http://www.newrailwaymodellers.co.uk/Forums/viewtopic.php?f=22&t=17719&p=466094&hilit=third+rail#p466094

Is a GREAT section about adding a third rail.

Trentbradbury
14th Mar 2014, 10:20 AM
http://i222.photobucket.com/albums/dd62/LondonResident/Scenics/Third-Rail-03.jpg

PW&NJ
14th Mar 2014, 11:20 AM
Yep, that's the one. Love how he used the sliced insulated rail joiners to hold the rail. :thumbs-up:

grrf
14th Mar 2014, 12:00 PM
doh, you beat me to it PW...YAY for insulated joiners!!YAY for Frankland!

ChicagoNW
14th Mar 2014, 02:47 PM
The insulated rail joiner thing sounds good.

I wonder how it works on a concrete tie with the angle outside the rails.
Do you think the glue will fill the gap?

It will be perfect on the L structure which uses wooden ties to dampen the vibrations.

I like how Frankland has two types of traction.

ChicagoNW
14th Mar 2014, 04:50 PM
Does anyone know if the Art Deco Flatts building is a kit? That is one sweet structure.

grrf
14th Mar 2014, 10:08 PM
I believe he scratchbuilt it from photos from google streetview
http://www.newrailwaymodellers.co.uk/Forums/viewtopic.php?p=429676#p429676


http://i222.photobucket.com/albums/dd62/LondonResident/Scenics/Hartington-Court-Plans.jpg

http://i222.photobucket.com/albums/dd62/LondonResident/Scenics/Block-of-Flats-14.jpg