For the technically minded, one of the available "free" references that covers railway design is Railtrack and Associated Equipment for Use in Underground Mines. by the UK Health and Safety Executive. The relevant standards of railroad rolling stock design are usually only available at a significant cost and many of the other "free" references like Google Books etc have arbitary page limitations that may hide the relevant pages on rolling stock design as applied to curves.
In the link I quoted, check out the curved track section. This section gives:
Minimum radius to prevent flange climbing and subsequent derailment Pdf page 19 to 21/84
Endthrow formula for the end of vehicles on curves - Pdf page 31/84
Centre Centrthrow formula for the centre of vehicles on curves - Pdf Page 31/84
Notice that the weight of the wagon plays no part in flange climbing.at the minimum radius. Simply adding weight will not help if your wheelbase is too long. Other topics covered are reverse curves, superelevation and gauge widening and checkrails.
For those that open the link, make yourself a cup of something. You might be there a while. This is not mainline stuff but the geometry of overhangs on curves is scale independent provided that you keep your measurement units consistent.
Unanderra in oz
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