Superelevated Curves on Grades? - Model Railroader Magazine

dknelson

The main benefit for superelevation of curves on a model railroad (given our larger than scale flanges and such) is visual interest.  One of the most important aspects for superelevation both model and prototype is to make it gradual, not a sudden lurch upward (or downward). ....  Don't overdo the height --- even modest super elevation gives the visual effect you want.

Of course you do not want a huge gap showing under the rails and ties so super elevation calls for careful ballasting of track.

Dave Nelson

A couple of things to look for in pics of the subject are:-

1. Heavily built up ballast shoulders - mainly or only on the high/outside rail side.  These may rise as high as the rail head - but will be clear of any low slung equipment that will pass on locos and stock.  They may extend further from the rail than standard ballasting... i.e. the cross section of the ballast profile will be wider.  They may cover the ties right up to the rail.  Any combination may apply.
2. Track and rail stabilisation.  You are looking for signs of track anchors - usually attached to the ends of the ties... usually the outer (high side) ends.  The purpose is to prevent the track being shoved out sideways.  You re also looking for rail anchors - in this case they would be fitted to the up hill side of tiies to the bottom of the rail.  These are to prevent the rail creeping downhill.  Eve in H0 you wouldn't actaully model these 'cos they are way too small BUT you might want to represent new ones with tiny flecks of paint... when new ones are installed they really do showup bright.  You don't need to do a whole lot... they get replaced in ones, twos and groups as required.  A length of new rail (different colour from surrounding rails) would have all new anchors... there is no way the MoW gang want to prise/whack the old anchors off a rail taken out.

What this is about in practice...

Especially if you have a combination of steep grade and sharp curve the loads being transfered from trains'wheels to the track will be trying to push the track in a straight line and down hill.  The job of the MoW is therefore to keep the track where it's supposed to be - both up/down the hill and sideways.

Both trains going up the hill and those going down will "work" the track.  Those going up are tending to push it back out from under them while those going down are tending to heap it up in front of them when they are braking hard.  Therefore any (normally) directional tracks will be reinforced whether they are up or down grade.

A down grade track may have patterns hammered into the head by the braking action.  There is no way anyone is going to model this (!) but it is an indicator of the forces being repeatedly applied. Somewhere I have a low angle pic looking down a grade that shows a fern leaf pattern  repeated all along the rail heads.

Rail wear/damage like this would cause rail to be changed out more frequently.  Two things apply...

1. Short lengths may be placed or racked at intervals ready to be switched into the track whenever a broken rail occurs.  This may be mirrored by the broken rails being thrown out or piled ready for disposal/collection.
2. The whole length may be lined up for replacement.  Depending on era you may have the 40' lengths or ribbon rail laid in place ready to be switched in.  Again this can be mirrored by the rails switched out waiting removal.  Rails can be laid beyond or on the tie ends or down the middle of the track... or any combination.  On double track you might even catch a transition stage where one line has been changed out and the other is waiting for the rail to go in - soyou get both patterns.

For the modeller the detail to note is the different colours of rails that are new,old or in between.  Broadly

1. new rail may be (new/orange) rust coloured or black (gunmetal) - this is all over... it gets more rust coloured the longer it stands... this may be uniform or in blended patches.
2. old rail in use/just taken out will have a shiny top and be whatever colour it has weathered to locally.
3. old rail that has been out some time varies from totally weathered all over/dark rust to the same as old rail in use but with a fresh rusted top. 

You can model some of each! 

If you have jointed track you can make life easy by just detailing on 40' length.  If you have rbbon rail you can "cut out" a fault and "weld in" a replacement as short as 15' (depending on RR).  Don't forget to model the welds!

How much visual interest do you want?

As routine maintenance the ballast on a difficult curve will be well maintained.  This can mean more frequent tamping and more use of a ballast grader to maintain the profile.  Both may mean that the ballast is topped up more frequently.This can be strips or patches of fresh ballast.  Fresh ballast is usually lighter in colour and therefore stands out.For the modeller this is really useful -

1. At any time after you've done your main ballasting - and weathered it - you can top up the ballast to fill in any holes that you spot or that develop... without needing to blend in the new material.  If you really want toget technical you can part blend some in and leave some really shiny and new.
2. You can use this to just "add interest" and/or to highlight... either of which can draw the eye away from something close by (like a board join) that you can't hide.
3. These add-ins can be done anytime.  So,once you've done the initial hard slog you can constantly improve the appearance of the track by smallincrements.

The fresh ballast can be track wide, down either side or the middle or any combination in strips or in patches.  Topped up ballast dropped in from hoppers will run on top of the ties unti lit gets tamped in and regulated.  (It's a swine to walk on).  It would be much easier to model strips of new ballast than the mix following working it into the formation... but the really keen might like to work on either a mix of ballast material that includes both dark (old) ballast and light (new) ballast...or (if it can be made to stick down) a sprinkling of light stuff might be added onto weathered ballast...

A more simple variant for double track is to have old ballast in one track and new in the next door track... There will be a pretty clear break line between the two colours... usually with any overlap being of the new stuff getting onto (or being thrown onto) the older track... when the new job is done any left over ballast in hoppers might be run out onto the un-renewed track (as top-up) if it isn't due for renewal soon.

You want details for ties and fishplates?