Bridge Height

[Anonymous]

What is the minimum distance, either scale feet or in actual inches, between the top of the rail and the bottom most part of a bridge or restriction a HO scale train may pass thru? I have a NMRA gauge but I am concerned with double stack container cars passing thru. Thanks in advance.

[cacole]

A double stack train will just barely clear the Walthers double-track truss bridge, which has slightly under 4" of vertical clearance in HO scale. If the bridge had 1/32" less clearance, the tops of the containers would hit it.

[Anonymous]

The minimum height from the top of the rails is 22 feet on the prototype. The NMRA standard is 3 inches, about .030 in. shorter than 22 scale feet in HO. What you have to watch out for is equipment tha is out of scale. Most of the time thebody of thecar will be scaled right, but it will be riding to high on the trucks. Over height equipment is a problem with the real railroads now a days. The best bet is to test taller equipment at all low clearance locations.

[rogerhensley]

For a good description of clearances and the NMRA gauge, you might want to read 'Standard S-7 Clearances and the NMRA Gage' at http://www.nmra.org/standards/gauge.html

This can help answer a number of question about prototype clearances, and how they relate to our models.