Re: Trivia - Double Slip points and 520/621

["Trevor Gibbs" <xdford@one.net.au>]

I lived and worked at Peterborough in the mid 70's and no there were no
double slips on the NG let alone a triple gauge version. There was only
Triple Gauge Point ever built and that was at Gladstone Yard. I think the
only NG double slip was in Quorn Yard which I was led to believe was the
only one in Australia until I went to WA and saw Double Slips on NG like
they were going out of fashion. AIRC, Bunbury yard alone had 7 that I
counted! 

Re 520/621 I posted this before but in case any one missed it...

All SAR Engines and Rollingstock post Webb ( 500, 600 and 700) were built
to be readily gauge convertible...

The wheels in all locomotives and rolling stock were slightly "dished" or
cupped shape so that by reversing the wheels relative to the axle and
tyres, the gauge could be widened or narrowed. The difference of BG to SG
is 6 and 1/2 inches so the
offset need only be 1 and 7/8" on either side of the axle, virtually next
to nothing in Railway terms. All steam engines had two brake hangar
positions but of course it was never required.

To add to this, there was a design of a 520 variant for the Commonwealth
with a large tender, and there was a possibility from what I remember
reading in old RT magazines that the SAR was to take over at least the Pt
Pirie/Augusta section and believe it or not convert it to BG in the late
40's or 50's... Such was parochialism!  

Trevor