Since some say that it's impossible* for Exact Scale trains to run successfully out of doors, here is Mark Wood's BR 4MT doing precisely that, in a natural scenic landscape on his Railway :
San Cheng BR 4MT, 1:32 Scale, Exact Scale wheels and Photo by Mark Wood
Here's how the scale wheels were made.
Contrasted with a similar locomotive to the same scale:
Bowande BR 4MT, live steam, 1:32 Scale, Standard wheels
Reality Check: In comparing the similar photos above, were your eyes drawn to the tyres - or not? Your answer tells you something about what matters to you, never mind anyone else.
* "There's no use trying," said Alice; "one can't believe impossible things." "I daresay you haven't had much practice," said the Queen. "When I was younger, I always did it for half an hour a day. Why, sometimes I've believed as many as six impossible things before breakfast." Through the Looking Glass, Lewis Carroll