Re: [VIC] Wooden cars at high speed (was: [VIC] Parallel run)

[pcc@ocean.com.au (Brown Family)]

On Sat, 15 Apr 2000 03:17:38 GMT, in aus.rail you wrote:

>E cars are not well known for hitting platforms. The large W cars did this
>more often as they were built to the limit of the loading gauge.
>
>What is interesting is to stand at the end of the corridor of an E car and
>watch the whole car flex. It's designed to do this. If it stops flexing,
>you're in trouble!
>
I've seen some E's, longer than  W's, sway alarmingly at speed. They
are simply not meant to sway. If you sway, you have loose rivets, worn
bolt-holes and metal fatigue. If you have metal fatigue, you have
cracked frames. Most carriages, in fact, did not sway  - even the V's

>E cars were designed to ride rough track at 80mph. The bogies have 3 axles
>not because of weight, but so there will always be at least 4 wheels on
>the track at any given time over rough joints.
>
C'mon David, with due respect mate. No rail bogie, this side of a
logging tramway, has ever been designed to allow wheels to leave and
rejoin the track. The sprung suspension, vertical-axle-travel and the
total unsprung mass are all designed to make sure that all wheels
contact the rail; if not, you derail. To even suggest that wheels
might leave and rejoin the rails in normal traffic is ridiculous. 

I remember years ago riding in Z-vans, guards used to joke about the
reason for six-wheel vans was because 2 wheels would always fall off
and jump back on - but it was a joke, or meant to be. 

The plain and simple reason for 6 wheel bogies was comfort - they were
in use all over the world at the time and in countries with far better
track standards than Victoria then. As soon as superior  suspension
became available in a four-wheel bogie, it was adapted and they had no
no fear that some wheels might leave the track. Four wheel bogies
would have been preferred because they were lighter than six and had
less unsprung mass. 

The V-class carriages, which pre-dated the E's, all had four-wheel
bogies and ran at the same speeds and the same tracks as the E's, and
often in the same train. There was no fear then of a V's wheels coming
off.

Les Brown
Freedom's just another word for nothin' left to loose.