On 17/11/2021 08:01, Matthew Geier wrote:
> If Melbourne stands fast on its requirement to have rotating bogies,

> both Alstom and CAF do have something to put forward. It's going to

> come down to if fleet engineering calls the shots or treasury.


I think that it is very likely that Melbourne will stick with its
requirement.

Melbourne learnt the hard way that not controlling tram selection is a
bad idea - although the Citadis and Combino trams never ended up off the
tracks for extended periods.

Even the 'successful' C2s are restricted to one route with minimal
vertical curvature.

As has been said so many times - and over many decades - it would make a
lot of sense to have an Australian standard tram - at least in terms of
the basic chassis and drive train configuration.

I'm not holding my breath for that one!

Matthew: Your photo of a CAF bogie shows the way it connects to the tram
body through closely spaced springs.

See: https://tdu.to/m/263305

I suspect that the cracks shown in the various pictures and described as
being around the 'wheel arch' are in fact around the tramcar chassis
where it attaches to the springs. It would be subject to enormous stress
due to the twisting of the springs.

Mal Rowe - who only did a couple of mechanical engineering subjects at RMIT