Scott, A closed frog turnout is typically one where the wingrail/closure rail assembly at the frog close the gap between the closure rail and rails that form the 'V' of the frog. This can be accomplished usually one of two ways. The points and wing rail at the frog pivot around an axis so that when the points close against the stock rail the wing of the closure rail of that point presses against the frog.
Another is a little flipper at the frog flangeway that points in the right direction filling the flangeway gap depending upon which position the points are in. These two approaches provide continuous rail without flangeway gap at the frog from point to frog. It eliminates the need for the guard rails at the rails opposing the frog. Guard rails that are designed to accept hi-rail wheels create flangeway guides that are too wide for scale wheels because they do not pull the truck snug with the opposing rail. This increases the chance that the wheels will pick the frog. If guard rails are designed for scale wheels, hirail wheel flanges don't fit and ride up over the top and can cause derailment. Ben Trousdale --- In [email protected], Scott Huston <steamtramper@...> wrote: > > Good Morning Pieter. > > This is the second time this week I have heard of a closed frog turnout. > Could you please explain what this is? I haven't heard the term before so am > unfamiliar with it. > > Thanks, Scott Huston, Las Vegas Nevada > ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/S-Scale/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/S-Scale/join (Yahoo! ID required) <*> To change settings via email: [email protected] [email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
