Brian Gaff <
brian...@gmail.com> wrote:
> I was going to say, the line gauges being different for different rail
> systems was always an issue. Some were of course built to be modified for
> similar if not the same gauges.
Many basic contractors' locomotive designs were sold as different models
to suit different gauges. Altering them later was often just a matter
of a few component changes and may not have even involved returning the
whole locomotive to the factory. Wheel sets, complete with their axles,
were often changed when the tyres became worn or developed flats during
the normal working life; it was a routine operation.
For light railways, such as temporary contractors' railways, the
narrower gauges has the advantage of allowing tighter curves and lighter
weight track. Track was often transported to the site in the form of
pre-assembled panels and was frequently pulled up and re-laid several
times as the work progressed, so track weight was more significant than
on permanent railways.
Re-selling a viable narrow-gauge contractors locomotive would not have
been as difficult as it first appears, but a worn-out specimen, which
had to be transported from an isolated location, might well have been
scrapped instead.