In the process of preparing to start track building I went back to Ian Rice's "An Approach to Finescale Track" for a bit of a refresher course. In the process of mulling over the various critical gauges and dimensions required, I found myself searching around the various forums etc. on the web for some more advice, and stumbled across a thread discussing 00-SF (otherwise known as 'EM minus 2' apparently).
I have to confess that until now I'd not really pinned down an exact set of standards to use, beyond the vague notion of '00 finescale' and had shied away from further investigation in the slightly foolish hope that I might be able to get everything to work purely by a process of trial and error (for which you might like to read 'wing and a prayer'!). So I was immediately grabbed by the proposition that here is a set of track standards that allow one to run R-T-R locos and stock (at least of the more modern varieties, which is all I will be using anyway) without any re-wheeling or re-gauging (again, something I have no desire to get into at the moment), on hand-built track that has considerably improved appearance and running quality over 'standard' 00.
Without getting too technical, this is achieved by using a minimum track gauge of 16.2mm (EM minus 2mm) with crossing flangeway gaps of 1mm. For more information, see the 00-SF Yahoo group. At first it may seem perverse to further reduce the gauge of what is already under-gauge track, in the pursuit of enhanced realism, but actually when you understand it it makes a lot of sense. Actually, the 0.3mm reduction in gauge is only a 1.8% reduction, so not really noticeable to the naked eye, but the real difference is in the 1mm flangeways, a 20% reduction which makes a noticeable visible improvement and apparently leads to much smoother running through turnouts.
This all seems to fit the bill quite nicely for what I'm looking to achieve, so I've made some enquiries on the 00-SF group about getting hold of some gauges so I can start building to this gauge. I've also re-jigged my Templot plan using the new gauge specification as for some reason I had it set to the BRMSB standard before (although, having already printed out the track plan and started cutting and sticking it into the various sections required for construction, I need to check whether its worth reprinting it or not - I may be able to get away with the BRMSB version and simply rely on the track gauges to achieve the correct measurements, as at first glance the actual flow and radii of the track etc. appears largely unaltered with the new settings).