Very large DIY finished at last

Jul 13, 2010 29 Replies

In article , John Weston scribeth thus

Ummm .. what's the difference between a Trolley bus and a Tram?...

tony sayer wibbled on Wednesday 14 July 2010 00:01

The trolley bus is trackless and runs like a bus on rubber wheels and is steerable, subject to the twin pickup poles being able to reach the wires.

I've been on both in Latvia. The trolley busses were prone to the pickup poles coming off the wires (age old problem I believe) - requiring the conductor to run out back and re-position them[1].

[1] I seem to remember the old British way in London was to use a long insulated pole to manipulate the pickup pole. The Latvian busses had the cables coming down onto a pair of spring loaded auto-retractor spools on the back (thing hoover cable rewind) - so the conductor would simple pull the electrical cables as a method to move the poles.

All of the overhead wire needs to be raised before people are allowed on the top deck. When at correct height, a seven foot person would have to stand on a seat and use an umbrella to reach the wire. The bodywork and seats are timber. There's no bare metal up top, but it will be earthed.

MOTAT: Western Springs Tramway:

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Tramway Museum:
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Tramway:
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thought there was another tramway too but I can't remember it.

Is the control method based on a Ward-Leonard system? I first came across it in the Army in the middle 50s, we eckies in REME were supposed to service the thing as fitted on a 40mm ack ack gun. Don

Basically the two motors are switched to be in series or parallel, and at low speeds the excess power is sent though several large resistances under the tram. They can get red hot if you drive the tram slowly with the brakes on, but why would anyone do that? (Answer, when you are making the rails flat with grinding blocks!)

The controller can switch to reverse with the small barrel on the right, and one motor can be disconnected using the levers on the left:

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Have a look at

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We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Tim Watts saying something like:

I was just old enough to encounter tram travel in Glasgow and recall the last tram being run; I had a penny flattened by the last Glasgow tram, as did many others, for years.

The pickup springing off was quite common, especially at trailing junctions, and quite frequently the restraining strap broke with the jerk as the pickup shot upwards, rendering the 'bus immobile. Istr the driver switched to battery power and pulled in to the side of the road until a repair crew could get out.

saying

That must have been a Trolley Bus rather than a tram. Trams ran on fixed rails so couldn't pull in anywhere!

AWEM

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "Andrew Mawson" saying something like:

Indeed it was, as I indicated.

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