Golden Rule

[Sumpter250]

Actually I was put off by On30 because there is now way to make an inside frame classic "narrow gauge era" 4-4-0 in O scale running on HO track. That is why I rubber gauged looking for 4-4-0's. The only ones were Sn3. I am not buying another $500 dollar loco kit and re-guaging HO to Sn3 is more bother than it is worth . If visual disparity between gauge and scale didn't bother me I would still be modeling the 1870's in OO scale running on HO track.
Harold

Regauging HO standard gauge to HOn3 is no fun either. That's the reason why I've set aside the HOn3 "dinky" mogul, I was trying to build from an HO 0-4-0.
"an inside frame classic "narrow gauge era" 4-4-0 in O scale running on HO track."
Finding a properly sized,scale, boiler and cab, to represent a 30" gauge 4-4-0 in On30,would be difficult. An outside frame 4-4-0 would, more likely, be easier to do. The boiler-cab-steam chest would be wider, and probably easier to find a suitable loco to start from.
Whatever the case, the loco's center of gravity has to appear (and be) low, and centered between the rails. If the loco looks too tall, or too wide........it then looks too improbable. This, in itself, rules out holding too tightly to "stated ratios of height and width".....good rules of thumb....but not fixed laws. The physics of stability are the fixed laws (until someone invents inertial dampers, that allow skyscrapers to be stable, balanced on a pin point, anywhere under the base.)

Ouch! One of the toe dancing hippo's from Disney's "Fantasia" just appeared in my mind's eye! hock: hock: