HO scale?!

HO scale is 1/87, S is 1/64, N is 1/160, O scale is 1/48

And, I Scale is 1/32 (also rendered as "1" Scale)

Note that HO is not "half O" as used to be bandied about.

If the scale ratios seem odd, recall that rail guage is like 4'-6-1/2" and that's being made a uniform span on the ties/sleepers (so that the rails are 3/8" or some such, apart), rather than a "uniform" scaled value like 1/72 or 1/150.

There also used te be a "TT" scale around, being 1/110

HO scale, S Scale, N Scale, its kinda confusing me....

First, thankyou for recognizing that it is "scale", and not, as the model railroading industry has mistakenly called it..."gauge"!  Standard gauge is 4',8-1/2", not 4' 6-1/2". Anything greater, ie 5' gauge, is called wide gauge, anything less, ie 42",3', 30",2', is called narrow gauge. G scale, is meter gauge, and the track is used in various "scales", to represent 3' gauge, standard gauge, 30" gauge. As a result you get #1 scale(1/32), and a variety of others, depending on the intended size of the equipment. Oh, there is a "T" scale, which is "T"hree milimeters between the rails. This is smaller than Z scale 1/220. There was a lot of 3' gauge used by the Allies in europe, to provide supply support to the advancing troops. O scale, originally was 7mm = 1 foot, or 1:43.55. 1:48 for O scale is an American invention. HO, is half O, or half of 7mm, or 3.5mm = 1 foot,or 1: 87.1

thanks for all the tips guys. u just made life alot easier!

In the old days there was Gage 0 (zero), Gage 1 and Gage 2.  Gage 0 (zero) became O (oh) gage, now O Scale.  Gage 1 or G gauge track is still sold by LGB, Bachmann, Arsitocraft, et al. The actual scale of G gauge varies from 1:20.5 (Bachmann) to 1:32 (Marx).  The common G scales seem to be 1:20.5, 1:24, and 1:29.