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

["Stuart Thyer" <s.thyer@anatomy.unimelb.edu.au>]

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In article <B5216B68.CB8D%markbau@altavista.com>, Mark Bau
<markbau@altavista.com> wrote:


>
>
>> From: dbromage@fang.omni.com.au (David Bromage)
>> Organization: Another Optus Customer
>> Newsgroups: aus.rail
>> Date: Tue, 18 Apr 2000 06:28:47 GMT
>> Subject: Re: [VIC] Wooden cars at high speed (was: [VIC] Parallel run)
>> 
>> As for swaying, the DERMs did that a fair bit too. RM61 lost a few rivets
>> against a few platforms on her final run to Bendigo in 1993.
>
>
>This is not rocket science! DERMs swayed a bit because they were rarely
>attached to anything, even a C class diesel used to sway all over the place
>when running light, but put some tonnage behind it and it was a different
>story. 

It doesn't help with the fact that DERMS are slightly wider than W cars,
which are considered pretty wide anyway. As for the swaying of an E car and
a DERM, it's totally different to what David started to describe. A DERM
would just rock from side to side, an E car will actually twist and flex as
it travels along, not as a result of loose rivets and fatigue as was quoted
earlier, but because they are 75' long on a lightweight steel frame with an
entirely timber body.
A DERM or modern steel car can incorporate the structural strength  of the
body into the overall design, an E or W type car can't, so movement is
allowed for.
I wasn't there in 1910 when the first E cars came out, but I'll bet they
flexed then and still do now.


Stuart Thyer
Photographer
University of Melbourne