ICRs

[jhb171achill]

Some of our modellers do the 21mm gauge track - it looks so much better!

[Mayner]

8 hours ago, LostCarPark said:

I've often wondered why we seem to prefer the UK scales (1:76 OO/1:148 N) when European scales (1:87 HO/1:160 N) would at least be a little more in scale with the track. I've occasionally thought it might be fun to model a railway that treated standard track as Irish gauge and built the models to scale with it (1:97 HO/1:178 N). But then I slap myself and realise it wouldn't be fun it would be insane.

OO 1:76 basically  evolved as a necessary compromise to allow mass produced models of British locos and stock to run on OO gauge track. Apart from the problems with the large motors of the 1920s & 30s into a HO body shell alluded to by the Minister, the larger scale was necessary to provide sufficient running clearance to allow models of British and Irish locos and stock run on small radius curves (less than 3') necessary for train set use and the majority of continuous run layouts in Ireland and the UK.

While its feasible to build a reasonably large OO gauge layout in a relatively compact space with minimum 2' radius curves, you would need to increase the minimum radius to 3' for a 21mm gauge layout using OO/HO gauge track & wheel standards or a min radius of 4' for a modeller working to finer P4 or S4 wheel and track standards.

While there is a certain attraction in tailoring the scale to suit an established track gauge particularly for narrow gauge models, it creates the additional problem of a model railway where the track is a different scale to the locos, stock, buildings, structures and vehicles. While 3mm scale appears to be a reasonable compromise for Irish broad and narrow gauge models, it aggravates the problems experienced by British modelers and manufacturers when they attempted to build HO scale British outline models in the 1920s.