I got to wondering how many feet you would need to make a mile in HO. Best I can figure is 60.7’ would be an HO mile. Am I on the mark or way off base? I figure there are 87mm in a foot, times that by 5280’ and that equals 60.6896551…and so on (feet), which should be an HO (1/87th) scale mile, right?
Forgive my inane question, but I was just wondering what size layout it would take to model a 1 Sq mile ho layout.
J.P.
Close Enough
You are right. HO is 1:87 (actually it’s 1:87.5 because it’s an odd mix of English and metric measurements - 3.5mm to the foot). So as long as you are using the same units, you divide by 87.
The units always have to cancel. So if you want know actual feet for a scale mile, you need to use 5280 feet, getting you 60.7 foot answer. Of it you want to know how many inches make 10 scale feet, you have to start with 120 scale inches and divid by 87.
–Randy
1:87.1
KL
An error in your little jump to metric in the first paragraph: there are 25.4 millimeters to an inch, times 12 is 304.8 millimeters in a foot. Not sure if that was a typo, but the rest of your calculation is close (actually 60.62 feet equals one scale mile in HO). As pointed out above, the real scale factor is 87.1
A one square mile layout in HO would be 60.62 by 60.62 (real) feet.
letssee…
3.5 mm/HOft X 5280 ft/mi = 18480 mm/HOmi;
(18480 mm/HOmi / 25.4 mm/in) / 12 in/ft = 60.63 ft/HOmi. QED