Is this junction design realistic?

[sub39h]

Hi guys,

 

I swear I'm now on the 100th iteration of my track plan. I think I may have FINALLY found a broad outline that I like! For one of my stations, I want 2 different 2 track main lines to merge into a 3 road station (with the outer roads being unidirectional, and the middle road being bi-directional allowing through trains to pass trains waiting in the outer platforms, and also a place for regional trains to terminate and reverse. Please find a photo below with the main lines coming from the right and from the reverse curve at the bottom. the start of the three platforms is at the top. The other side of the stations sees the 3 roads merge down further into 2 and the line continues from there as 2 tracks. 

 

The lines going to the right are meant to be a fast line to London from somewhere in Yorkshire/Midlands (the layout will have no fixed location) and the lines coming from the bottom are to be a commuter/goods line. 

 

I have copied it three times, with the middle version highlighting in red the routes for trains going "down the screen" through the main platform and onto the two available routes, and on the right trains going "up the screen" and into its main platform. I have deliberately made the junction quite complex for the sake of visual interest. Similarly, the reverse curve is also there for visual interest. However I am wondering if I've made any glaring errors in terms of operation and i you had any suggested improvements.

 

it is OO gauge using Peco Code 75.

 

TIA

[The Stationmaster]

Apart from the diamond it's a fairly good representation of some 'modern' track layout ideas so I think it's ok and should look quite impressive.

[sub39h]

Thanks for your input - I have always wondered why diamonds are not favoured on the prototype? In my design surely it would be better for a train to carry straight on rather than have to snake through a ladder in a series of S bends? And surely a train could run at a higher speed on a layout like mine rather than a series of ladders? I mean high speed isn't the aim of the game on this section of my railway, but from a physics point of view I would have thought my solution was better than a ladder?

[cromptonnut]

Nothing wrong with the diamonds per se but I think the point Stationmaster may be trying to make is that 'straight' diamonds are very "model railway" whereas if you look at a junction normally the diamond is curved on at least one track.

 

Have a look at the first image on this page http://homepage.ntlworld.com/russelliott/3rd-4th.html and it's clear what I mean on the very top image - but just to prove the point the second image is a very straight diamond!

 

Curved diamonds are one reason people hand-build track   Sometimes sectional diamonds look right, sometimes they just jar and spoil the visual look.

 

This is for an american design but the prinicples remain the same, particularly for the visual look. http://coxy.squarespace.com/coxys-n-scale-and-railroad-bl/2007/3/31/curved-diamond-crossings-for-the-mn-rr-part-7.html

[TheSignalEngineer]

Apart from the diamond it's a fairly good representation of some 'modern' track layout ideas so I think it's ok and should look quite impressive.

If the speeds through the junction are low, and by the look of the curvature they will be, there is not really much of a problem with the diamond. I have seen similar layouts in the past with a 70/20mph speed, but the cross-levels and cant were difficult to maintain.

 

In relatively modern layouts the Regional Investment Manager would have cut the budget and got rid of the diamond without anything to replace it, making all trains to the Branch go through the Bi-directional line. Very restrictive and an absolute nightmare to operate when the timetable gets out of sequence.

[sub39h]

Nothing wrong with the diamonds per se but I think the point Stationmaster may be trying to make is that 'straight' diamonds are very "model railway" whereas if you look at a junction normally the diamond is curved on at least one track.

 

Have a look at the first image on this page http://homepage.ntlworld.com/russelliott/3rd-4th.html and it's clear what I mean on the very top image - but just to prove the point the second image is a very straight diamond!

 

Curved diamonds are one reason people hand-build track   Sometimes sectional diamonds look right, sometimes they just jar and spoil the visual look.

 

This is for an american design but the prinicples remain the same, particularly for the visual look. http://coxy.squarespace.com/coxys-n-scale-and-railroad-bl/2007/3/31/curved-diamond-crossings-for-the-mn-rr-part-7.html

 

Oh ok that definitely makes sense. I swear the bottom photo from the UK link you provided is on the DLR though. Does that count? 

 

Anyway I agree that ideally I would have like to have the curve from the "London line" a single uniform curve rather than having to briefly straighten for the diamond but with the limitations of RTR I don't feel it looks TOO bad. 

 

I have actually emailed Peco recently asking for curved diamond crossings. They'd definitely looks miles better. 

[Chris Turnbull]

Anyway I agree that ideally I would have like to have the curve from the "London line" a single uniform curve rather than having to briefly straighten for the diamond but with the limitations of RTR I don't feel it looks TOO bad. 

 

 

You can put a slight curve into a Peco diamond crossing which will improve the looks no end.  Cut the webbing on the underside of the crossing on alternate sides and gently bend it.  You won't be able to cut every web but you can cut some.

 

Chris Turnbull 

[GWR00N]

Be interesting to se the wiring diagram for that part of the track plan.

[sub39h]

Be interesting to se the wiring diagram for that part of the track plan.

 

haha we'll cross that bridge when we get to it! 

[The Stationmaster]

Thanks for your input - I have always wondered why diamonds are not favoured on the prototype? In my design surely it would be better for a train to carry straight on rather than have to snake through a ladder in a series of S bends? And surely a train could run at a higher speed on a layout like mine rather than a series of ladders? I mean high speed isn't the aim of the game on this section of my railway, but from a physics point of view I would have thought my solution was better than a ladder?

As others have hinted - albeit in slightly different ways - diamonds came to be frowned on for several reasons but the most important was the difficulty of maintaining them, and indeed providing them at all, to cope with the increase of train speeds which occurred from the late 1960s onwards.  Add in the sort of junction simplification mentioned by Signal Engineer and they simply ceseased to be used in many junctions and were increasingly only found in low speed layouts in the approaches to major stations.