Again, thank you and most interesting. The late Mike Sharman was, I believe, sceptical about track gauges and I agree; he said that waving a hot soldering iron around at track building cannot guarantee correctness of gauge, and I confess to relying more on a pair of digital calipers to check gauge-the results can be surprising. A couple of gauges do, however, help with holding things in place.
I also agree with the gauging of plastic centred wheels in the theory of some ‘bounce’ if a gauge is forced between them too firmly.
I wonder if the EMGS might consider the re-introduction of an ’18mm dead’ track gauge for EM-SF? The flangeway can be set by a pair of .8mm drills held in a vee shape with tape, and the .8mm check chairs are already available.