What colour is catenary wire?

I guess it depends when & where. A lot of early British catenary (including some 25kVAC inastallations) appears to be green (a form of copper oxide), but later installations look to be more grey in colour. Go and observe the real thing! Cheers, Mick

Get some phosphor-bronze and leave it outdoors for 20 years. ;-)

The copper contact wire should be shiny on the bottom where the pantograph polishes it, green around the top and sides where the copper has oxidised. On older installations the catenery wires are also copper and thus green, on newer installations only the contact wire is copper the catenery and droppers are galvanised steel and therefore dull grey.

Keith Make friends in the hobby. Visit Garratt photos for the big steam lovers.

=>If I recall my O level chemistry from 35 years ago, copper oxide is =>black. The green colouring is copper chloride IIRC

There are several copper compounds in the "verdigris" that forms on copper (and some copper bearing alloys, such as bronze). Fresh verdigris is indeed a bright green, but tends to dull towards darker greyish green and even black as sulfur is also taken up.

Nowadays, catenary wire will be dark green or even balck, on account of the sulfur in car exhausts, etc. Copper sulfides are black.

HTH

i'd certainly like to but the real thing I'm actually modelling is in Japan!

Thanks everyone for the replies, here and via email. I've sprayed the catenary a dark grey/green colour, and although I have no idea if it matches the prototype, it doesn't look too bad. Certainly a lot better than the bright copper colour it came out of the bag in!

Pete

=>i'd certainly like to but the real thing I'm actually modelling is in =>Japan!

There's lots of catenary in Japan ... and the technology is international.

Strictly speaking the catenary is the upper wire which carries the current and the weight. This has always been copper but turns black with age.

The lower contact wire used to be copper but is nowadays aluminium to save weight and cost. This also turns black with age.

kim

"KimPateman" wrote

So why is the entire catenary wire on the Crewe Independent lines vivid green?

John.

Sorry Kim but no way. It's the other way around, the contact wire is always a hard wearing alloy of copper, the catenary wires used to be copper but to save cost changed to a steel/aluminium composite. Keith Make friends in the hobby. Visit Garratt photos for the big steam lovers.

Copper (II) Hydroxide - what you get when copper oxide gets wet.

In message , Mark W writes

Thanx. I stand corrected. (I did say my chemistry was from 35 years ago, obviously it got rusty :-) )

"John Sullivan"

Almost tarnished your reputation.

-- Cheers Roger T.

Far be it from us to corrode your self esteem.