Linea aerea completa

Overhead line – January 2019

We are going on with the layout overhead line installation. The station poles have all been built and placed. Now let’s weld the catenary in place, but first….

First we give ourselves a gift! The small shunting locomotive from Black Star, DCC full, with power pack … incredibly realistic speed without hesitation, it will replace the D213 Roco. Below is a demo video.

Kof Black Star
Kof Black Star

And after playing a little with the small Kof, let’s begin to weld the catenary over the second station track. The contact wire is tensioned between two points, one fixed and one mobile for automatic adjustment as in real railway overhead systems. We use a cardboard template to weld the droppers.

Catenary cardboard template
Catenary cardboard template

After the catenary welding over the second track (depicted in yellow) and the usual alignment tests performing (see video below), we proceed to weld the catenary between the even access track and the fixed tensioning point (depicted in orange).

Catenary diagram
Catenary diagram

We need to anchor the catenary to the tunnel located at the left entrance of the station. For the portal construction please refer to  this article. We then glue the portal on its place and fix the clamps and catenary tensioners.

Catenary anchorages
Catenary anchorages

In the picture the processing nearby the portal has been concluded.

Overhead line near the portal
Overhead line near the portal

View from the gallery.

View from the gallery
View from the gallery

A detail of the high voltage circuit breaker pole..

Detail of high voltage circuit breaker pole
Detail of high voltage circuit breaker pole

We have also made some warning plates for the overhead line. The drawings were made with CAD with the Italian Railways typical font.

Warning plates
Warning plates
Warning plates
Warning plates

We are now going to tension the catenary over the third track using a nylon wire thruoghout the pulleys of the automatic tensioning device. For the operation of this system please refer to  this video.

Automatic tensioning system
Automatic tensioning system

We intercept the nylon wire sub-board and connect it to the wire coming from the winch by means of a compensation spring. We turn the knob and stretch the contact wire.

Sub-board winches
Sub-board winches

It’s time to weld the contact wire. This is the complex part of the work. Right tensioning is needed before welding the wire to the clamps. We use the adjustments knob for testing the load along it. In fact, this is always more rigid at the ends than at the center of its length.
Once the load has been determined, we proceed with the welding as shown in the image. Watch the test video below. 

Contact wire welding
Contact wire welding

We now weld the catenary wire, leaving it very loose for bending without lifting the contact wire. So it’s time for droppers… and there are always a lot of them!
Droppers are L-folded to easily weld them with the upper side of the contact wire, which thus remains free in the lower part to ensure the pantograph friction bands free sliding .

Catenary wire and droppers welding
Catenary wire and droppers welding

At the end of this phase, the catenary is painted with a very dark green.

Catenary painting
Catenary painting

Before welding the catenary on the 4th track, we install the station lamp posts on the second platform.  

Lamp posts installation
Lamp posts installation

We are to the end of this adventure. It is well known that the construction of the overhead line is a complex, long and sometimes boring job, but the scenic effect is definitely satisfying in the end. Of course, we have not finished placing poles and wires, there is still a small part on the main route and all the poles of the upper line, still to be built. This will be the next step and we are already designing the needing models..

Overhead line completed
Overhead line completed

Below is a short collection of videos.

Railway maneuvers with Kof
Overhead line test on the 2nd track with a narrow friction bands pantograph
Overhead line test on the 3rd track with a narrow friction bands pantograph

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