David,

I build Gauge '3' engines (not 5" ) so I naturally build them to the G3 track standards because I want my engines (and stock) to run on G3 tracks here in the UK. These tracks have turnouts (points) that don't generally exist on MES tracks. Some of my " 2.5 inch " engines (as acquired) had huge flanges that would have been quite happy on a MES 2.5" track (because they don't have turnouts) but would never (in a month of Sundays) have run on a G3 Garden Railway without change.

You are based in UK. If you want to run 5" on an MES track- then you don't need to worry too much about the finer points of flange width etc – just make sure the engine's gauge is 5".

Whilst the Aussie standards may be perfectly fine (I have no idea) they are of course 'Aussie' standards – and you are not in living in Australia. If you want to run at ground-level 5" in the UK – then clearly the 5GL standards are the ones you need to use (unless you intend to emigrate to Australia of course) because the tracks you will want to visit here in the UK – have (I believe) been designed to support this standard.   

Regards,

IanT

Edited By IanT on 04/12/2020 23:51:11

Brian,

The Southern Fed website refers to the old EIM articles (by Martin Baker) about wheel & track standards – as well as referencing 7 1/4" gauge standards. But I wouldn't say that there is much immediate (useful) information there for folks seeking clear guidance on these matters (I don't know about the Northern Assoc.)

Whereas the GL5 Group have very clear, well documented track & wheel standards on their website. If I was just getting into ground level 5" running – then this would be the way I would go. They can be viewed here.

GL5 Track & Wheel standards

Regards,

IanT

Brian

Comparison of GL5 and Southern Fed standards.