Beck Line..

In going through my notes, I can't trace two authours so
will have to restart, in any case the previous route is of BVE 2
generation, not the current standards..

So I'd therefore like to request from this forum the assistance
of those that have specfic skills to enable the construction of
a 'quality' BVE route, depicting appropriate engineering practice.

To start with I would like some asssitance in calculating some enginerring tolerances, in respect of what 38 stock can handle
in terms of curves and platform lengths..

In my fictional history- Part of the Beck Line would have been
contemporary with the 1938 stocks introduction..

(I'm assuming that 7 Car running would have been built in respect
of a line nominally planned pre-war)

Wikipedia suggests likley formation of 38 stock trains would have been,

DM 52' 3 3/4" = 159449
T 51' 2 3/4" = 156147
NDM 51' 2 3/4" = 156147
DM 52' 3 3/4" = 159449

DM 52' 3 3/4" = 159449
T 51' 2 3/4" = 156147
DM 52' 3 3/4" = 159449

So this gives...
VERY roughly 400ft platform lengths on the late 40's ex Picadilly
section of the Beck,(Holborn->Aldwych -> Waterloo->Kennington->
Lambeth -> Camberwell - Milkwood -> and what would have
been (Brixton)..

These platforms would need lengthening for Full Beck Phase II 7 car operation.

All new build Beck Stations(Euston, Russell Square,Holborn S/B, Herne Hill and stations to East Cryodon) would be built for 7 car at (125m).

Does anyone have the figures for platform clearances so I know
how tight a curve I can reasonably make at Waterloo and Camberwell?