Can someone explain scales for me?

[TorqueVR]

I think I'm a fairly sensible person and I can understand why die-cast and plastic kits are commonly 1/12 18, 24, 32, 48 and 72. There's a sense of logic. I can also understand 1\144, and 1\350 for warships.

But a couple of things irk me. If I understand correctly H0 is 1/76 so why not 1/72 to match the planes etc, or vice versa, and what's the difference between H0 and 00? And where on earth did 1\43 for die cast cars come from? It's such an odd number.

Don't get me wrong, I am not complaining, just perplexed. I have have collections of 1/72 aircraft and 1/43 cars and they fit the display cabinets well so is this why the scales have come about?

[Foliage]

1/72 is half inches to a yard.
1/42 is half inches to a foot, not sure why they went to 1/43

[CanAm]

The odd sizes are to do with model railways. HO I think is 4mm per foot and 1/43 is O gauge at 7mm per foot.

[TorqueVR]

So why on earth 4mms and 7in per foot? It seems even more bonkers than I imagined.

[CanAm]

I Think because the railway model makers were European but full size Railway gauge was Imperial ( a nice round 4ft 8 and a half inches).

[MBBlat]

HO is 1:87, being half O gauge in size, and the 16.5mm track is correctly scaled for 4'8 1/2" standard gauge lines. However British loading gauge, ie the size of trains, being smaller than our continental friends when the first British outline trains were made the manufacturers couldn't it the mechanisms in the body, so they were slightly enlarged to 1:76 to give OO, still running on the same gauge track, which means the track is underscale.

A similar thing happened with N gauge, 9mm track, with European & USA trains being 1:160 and UK being 1:148. Strangely enough Japan uses 1:150, ie essentially the same as UK scale, to represent trains running on narrow gauge track.

Go to the larger sizes and it gets really confusing, with several different scales all using the same track gauge, and some scales using 2 different track gauges

[Yertis]

TorqueVR said:

So why on earth 4mms and 7in per foot? It seems even more bonkers than I imagined.

And 2mm per foot in British N. I think it's just happy coincidence.

[DIW35]

CanAm said:

The odd sizes are to do with model railways. HO I think is 4mm per foot and 1/43 is O gauge at 7mm per foot.

Not quite right. O gauge is indeed 7mm to the foot, but HO is 'Half O' or 3.5mm to the foot. OO is 4mm to the foot, but runs on the same track gauge as HO. This means that the width between the rails is slightly under scale on a OO layout.

I understand that the historical reason for this is that the outline of British locomotives is slightly smaller than the locomotives found on European railways and, in the early days, to make enough room inside the model locos for the motor, British toy makers opted for a slightly larger scale.

No idea if that is actually true or not, but I am sure I have read it somewhere.

[CanAm]

Weird, isn't it. It makes a bit of sense for railways, but one of the few countries using Imperial measurements, USA, has historically used 1/25 scale for cars rather than 1/24. Yet in metric countries you find 1/24, 1/18 and 1/12. You'd think 1/10 and 1/20 would be more popular.