A problem I've always run across when track laying is deciding what size of turnout to use in a given area. This is especially true in cases where I haven't yet given the region in question a roughed out roster, as ultimately from a prototypical standpoint, one would be limited in their engine/car choices based on the track curvature that they can handle.
What I would like to do is compile some sort of reference table to roughly outline what turnouts and/or curve radii would be able to accommodate cars and locomotives of a given size or wheel arrangement. Not anything overly specific (as total rigid wheelbase can and does often vary wildly between locomotives of the same wheel arrangement) but rather something more of a 'in the ballpark figure' guesstimation.
I know that NMRA's website has something similar to this, but the way their car classifications are listed are a bit technical - especially if you're just wanting to drop something onto the tracks and go and don't want to fuss with having to manually look up or measure the equipment in question's wheelbase to make sure it makes the cut when it would be much faster to just say, look up a list of compatible turnouts by frog number for a general 4-8-4 locomotive and be on your merry way.
The other issue I have with the NMRA Standards in this regard is that given the limited scope one typically has to model a scale railroad, most models tend to have much smaller turnout and curve radii than would normally even be possible for them, so I'm hesitant to use the existing data as-is as some of the minimum turnout listings look a bit fudgey.
So, what I'd like if anyone would like to contribute is to provide some input or experience on what turnout types tend to work best for their rolling stock.
Here's some of the things I'm looking for:
Locomotive wheel type (either Whyte Notation or UIC Classification. Common names [i. e. Pacific, Northern, American, Ten-Wheeler, etc.] are fine too) From here a generic value for the rigid wheelbase could be established, rounding to the largest wheelbase (within reason) for that wheel type is preferable - that will ensure both the smaller and larger engines will still be able to negotiate the curve.
Or alternatively rolling stock grouped by common car-length measurements (i.e. 40ft boxcars, for example). Be sure to specify the presence of any diaphragms on passenger and express freight cars, if applicable.
Now here's where things get tricky. I would ideally like to have 4 different classifications for turnouts for each wheel type/car length. Something along the lines of 'High-Speed, Normal, Impaired Clearance (Reduced Speed through turnout), and Impassible.
High-Speed turnouts intended for Fast Freight/Highballers/Express Trains to pass through at atypically (at least as far as general speed restrictions) high speeds.
Normal/Standard Turnouts are for freight and passenger trains traveling at full speed, but not fast enough to require a high-speed turnout (such as mainline industrial division points, branch line junctions, etc.)
Impaired clearance would be for anything that's small enough to cause the engine to need to pass through at restricted speed (equiv. to a 'yellow aspect') for the entirety of the train. This listing would be the bare minimum the equipment would be able to handle (barely!) without derailing or jumping the track.
Impassible turnouts would be anything below Impaired Clearance. The train should under no circumstances attempt to pass further than the clearance point unless without express orders or special provisions for the situation, lest the engine jump the track and make a real mess of things.
With enough data I'll try to compile it all onto a nice little spreadsheet file for everyone else in the event anyone else ever asks (though given the frequency of questions about turnout/curve sharpness, that's a give anyways :hehe: )
What I would like to do is compile some sort of reference table to roughly outline what turnouts and/or curve radii would be able to accommodate cars and locomotives of a given size or wheel arrangement. Not anything overly specific (as total rigid wheelbase can and does often vary wildly between locomotives of the same wheel arrangement) but rather something more of a 'in the ballpark figure' guesstimation.
I know that NMRA's website has something similar to this, but the way their car classifications are listed are a bit technical - especially if you're just wanting to drop something onto the tracks and go and don't want to fuss with having to manually look up or measure the equipment in question's wheelbase to make sure it makes the cut when it would be much faster to just say, look up a list of compatible turnouts by frog number for a general 4-8-4 locomotive and be on your merry way.
The other issue I have with the NMRA Standards in this regard is that given the limited scope one typically has to model a scale railroad, most models tend to have much smaller turnout and curve radii than would normally even be possible for them, so I'm hesitant to use the existing data as-is as some of the minimum turnout listings look a bit fudgey.
So, what I'd like if anyone would like to contribute is to provide some input or experience on what turnout types tend to work best for their rolling stock.
Here's some of the things I'm looking for:
Locomotive wheel type (either Whyte Notation or UIC Classification. Common names [i. e. Pacific, Northern, American, Ten-Wheeler, etc.] are fine too) From here a generic value for the rigid wheelbase could be established, rounding to the largest wheelbase (within reason) for that wheel type is preferable - that will ensure both the smaller and larger engines will still be able to negotiate the curve.
Or alternatively rolling stock grouped by common car-length measurements (i.e. 40ft boxcars, for example). Be sure to specify the presence of any diaphragms on passenger and express freight cars, if applicable.
Now here's where things get tricky. I would ideally like to have 4 different classifications for turnouts for each wheel type/car length. Something along the lines of 'High-Speed, Normal, Impaired Clearance (Reduced Speed through turnout), and Impassible.
High-Speed turnouts intended for Fast Freight/Highballers/Express Trains to pass through at atypically (at least as far as general speed restrictions) high speeds.
Normal/Standard Turnouts are for freight and passenger trains traveling at full speed, but not fast enough to require a high-speed turnout (such as mainline industrial division points, branch line junctions, etc.)
Impaired clearance would be for anything that's small enough to cause the engine to need to pass through at restricted speed (equiv. to a 'yellow aspect') for the entirety of the train. This listing would be the bare minimum the equipment would be able to handle (barely!) without derailing or jumping the track.
Impassible turnouts would be anything below Impaired Clearance. The train should under no circumstances attempt to pass further than the clearance point unless without express orders or special provisions for the situation, lest the engine jump the track and make a real mess of things.
With enough data I'll try to compile it all onto a nice little spreadsheet file for everyone else in the event anyone else ever asks (though given the frequency of questions about turnout/curve sharpness, that's a give anyways :hehe: )