Looking down on the roof of a tram it seems one end is painted black, the other a white/grey. Is there a reason for this.  The trams seemed mixed in which colour pointed north. On a slightly related matter how are trams turned. (or are they ever turned?)  Are there turntables at some depots. Can't remember seeing any triangles on the suburban network.

Looking down on the roof of a tram it seems one end is painted black, the other a white/grey. Is there a reason for this.  The trams seemed mixed in which colour pointed north. On a slightly related matter how are trams turned. (or are they ever turned?)  Are there turntables at some depots. Can't remember seeing any triangles on the suburban network.

What trams are you talking about? If it's a Melbourne tram that's just a build up of dirt or pantograph crud.

As for turntables ,depots in Melbourne don't have turntables. The old cable car barns did though.

What trams are you talking about? If it's a Melbourne tram that's just a build up of dirt or pantograph crud.

As for turntables ,depots in Melbourne don't have turntables. The old cable car barns did though.

I was on about the 4th floor along St Kilda Rd so had a good view of the tram roofs. It was definitely all the Z class, and possibly some A's could have been in there too.  The colouring covered the front 3 meters or so, and included the drivers air con as well. If it was dirt not sure why end would be totally clean and the other dirty. It afflicted all trams exactly the same in terms of the area that had been sprayed. Maybe it is naturally a grey/white colour but only one end ever gets washed!.

The pantograph is closer to one end.  This has a carbon strip across it which as it is dragged along the overhead trolley wire very slowly decays through friction leaving a fine grey - black deposit around the pantograph end of the tram.  That can sometimes also appear as a dark line along the mid-line of the roof.  One end will therefore be cleaner than the other when seen from above.

Trams are routinely cleaned but this does not include the roof owing to the risk of electrocution.  Even when in depots with the pan lowered there is a risk of accidental contact with the overhead and it is not usually practicable to isolate the current until the depot is full for the night.  By that time it can be difficult to access the roof with trams parked tightly alongside each other.

Trams are not turned.  There is no need to do so.  They have driver's cabins at both ends.

The pantograph is closer to one end.  This has a carbon strip across it which as it is dragged along the overhead trolley wire very slowly decays through friction leaving a fine grey - black deposit around the pantograph end of the tram.  That can sometimes also appear as a dark line along the mid-line of the roof.  One end will therefore be cleaner than the other when seen from above.

Trams are routinely cleaned but this does not include the roof owing to the risk of electrocution.  Even when in depots with the pan lowered there is a risk of accidental contact with the overhead and it is not usually practicable to isolate the current until the depot is full for the night.  By that time it can be difficult to access the roof with trams parked tightly alongside each other.

Trams are not turned.  There is no need to do so.  They have driver's cabins at both ends.

Thanks. Yes - that could well explain it. Damn. Wish I had taken some pics to see if it was always black at the panto end. Will check next time I have a the chance.  Now why didn't I work that out!

Even if a tram needs to be turned there is a number of triangular intersections across the network.  The most typical case is with the Restaurant trams.  On one side the door is blocked by a microwave oven, so in normal service only the door on one side is used.  That's why after the dining concludes they need to use the Port Junction crossover to access the down track to set down patrons before shunt back to car-in, instead of setting down on the up track.  The route is thoughtfully selected so that normally trams would return with the ends unchanged at the depot, but in case of service disruptions necessitating re-routing, they might need to be turned at the nearest triangular intersection, Bourke & Spencer Sts., to have the correct position for the next car-out.  They would run to Lonsdale St., shunt, turn left into Bourke St., shunt, turn left into Spencer St. then car-in.  You can also do it the other way around, but right turns are always more difficult than left turns.