Your advice on a station throat please

[cromptonnut]

I'm working on a terminus station as part of the RMWeb "modular" stuff, meaning I am restricted to 18" wide boards.  I've got 12ft in three 4ft long boards set aside for this.  I've got a 'station throat' design which does everything I need - allowing arrival and departure on all four platforms, and certain route combinations allowing simultaneous arrival and departure if required.

 

I want to get the complex pointwork all on one 4ft board to give me a long enough platform length for a pair of 4-CEPs, and I've come up with the following solution - using Peco code 75 trackwork, mostly long radius points, and it does the job but something I can't identify is bugging me that it doesn't quite look right.  I know I could handbuild trackwork to get a better flow but that isn't an option for me at this time, and unfortunately neither is Peco curved points or three way points as they go lower than the required 36" minimum radius.  I know technically the double slip also doesn't suit the standard but I don't see any other way.  I still have two platforms out of the 4 that do not use the slip in case we have any kitbuilt stock that won't handle 36" curves.

 

This is the section - the platforms have crossovers in them to allow run-round for loco hauled services although I envisage most stock movements being multiple units.  I've only shown the throat to make life easier.

 

 

Any suggestions gratefully received.

[Joseph_Pestell]

First up, as already mentioned elsewhere, the Peco double slip has a "nominal radius" of 36". That means that it deviates by 12 degrees (1/30 of a full circle) in about 8". (2 x 3ft x 3.142 = 20ft / 30 = 8") But in reality the slip curves are concentrated into much less than eight inches so the real radius is only about 24" which will give a problem to kit-built steam locos.

 

But apart from that, you are right that the layout is not quite right to follow most prototype situations with too many movements, particularly inwards to platform 2 (counting from the bottom) using the slip.

 

Proper solution may need a scissors crossover (e.g. Shinohara) but that won't conform to the Code 75 norm.

 

Worth repeating also that you are not limited to 18" (or 20") except at the end interface of the module.

[Joseph_Pestell]

I will have a look again later at this over morning coffee.

 

It may be you can solve it more easily with two island platforms rather than one island and two side platforms.

 

Y-points and 3-way points may also help out.

[maunsel]

I know what you mean. It all works, and could function properly but somehow doesn't look the part?

 

I don't think the design is wrong, but I could make a couple of suggestions.

 

Firstly, is the double running line from the top platforms necessary? How about an extra double slip:-

 

 

Secondly, is the double slip de rigueur? Looking at terminus throats the more popular option appears to be:-

 

 

Then thirdly, there is the siding at top right. Is this for parcels or a loco storage siding? If it was for the released loco wouldn't be on the arrivals side?

 

 

or even:-

 

 

or possibly:-

 

 

Although this impinges on the platform board with the turnouts and uses two short peco code 75 turnouts for the loco loop/siding.

 

 

Hope this helps!

 

Eric

 

 

 

 

Hopefully I haven't missed the point of your post. But it's worth repeating I don't think your initial design is wrong.

[cromptonnut]

Thanks all for the advice so far.  You are of course right that I only need 18" at the end of the module and could go out to 2ft (or wider if I really wanted although that may prove problematic in my Fiesta) for the station itself. 

 

Obviously the scissors crossover won't fit for the modular 50mm track spacing unless I trim the diamond; a possibility but not a preferred option.  Point taken also about the double slip - although I personally don't have or intend using 'kit built stock that may have a problem with 36" or less' when you are at a modular meet you may find people who do have stock that won't go round less than 36".  Primarily I am building the station for "my entertainment" with modular connectivity a necessary but secondary issue.

 

As it's not a "busy urban terminus" in the Minories style simultaneous arrivals/departures is not critical; however it's nice to watch

 

I like the "two island platforms" reworking idea.  I'll give that some thought but am very grateful for the differing opinions and interpretations of a fairly "normal" concept of two lines into four platforms.  Keep 'em coming!

[Peter Kazmierczak]

It looks a bit too symmetrical to me and lacking in some parallel moves, though nothing major. Will have a think and report back later.

 

I presume the top siding is a loco spur; don't forget about the trap point.

 

Are we talking modern era or something earlier?

[cromptonnut]

Peter, it's set in the 1980s or thereabouts.

 

The top siding was intended as a loco spur, although in reality it would probably be rarely used and somewhat overgrown.

[Joseph_Pestell]

I think that era is perhaps key here.

 

By 1980, most locations had been "rationalised". Single lead junctions had become the norm and double-slips (and diamonds) eliminated wherever possible.

 

I like Eric's last option but with the right-hand of the two slips being a diamond.

[cromptonnut]

I think that era is perhaps key here.

 

By 1980, most locations had been "rationalised". Single lead junctions had become the norm and double-slips (and diamonds) eliminated wherever possible.

 

I like Eric's last option but with the right-hand of the two slips being a diamond.

 

It's also "somewhere southern, third rail" if that makes any difference.  The problem with the last plan is that short points are not permitted within the modular rules.  As I only intend using ready to run stock it isn't relevant to me however I do need to "maintain the standards".

 

Regarding the last plan with "the right of the slips being a diamond", how do trains get to the second platform from the bottom from the incoming (lower) track?

[eastwestdivide]

Do you really need four platforms? 

[cromptonnut]

Do you really need four platforms? 

 

I suppose not, in all honesty... I could model an overgrown, disused platform with the track removed I guess?  That would still leave three platforms, and remove some of the associated trackwork issues.  But forgetting that completely and just making it three platforms would still work for what I have in mind.

 

A good point which I hadn't actually considered beyond "ok 4 platforms would look nice" and going from that basis.

[maunsel]

It's also "somewhere southern, third rail" if that makes any difference.  The problem with the last plan is that short points are not permitted within the modular rules.  As I only intend using ready to run stock it isn't relevant to me however I do need to "maintain the standards".

 

Regarding the last plan with "the right of the slips being a diamond", how do trains get to the second platform from the bottom from the incoming (lower) track?

 

Ah I wasn't aware of the "rules". I only put the short turnouts in for the loco release. Personally I wouldn't have included the loco spur, but would have  had it further down the line.

 

For some reason I put two short turnouts in Plan 1. This should have been:-

 

 

Then of course there's the two platform option, and two platform with central loco release line.

 

 

Eric

 

[Joseph_Pestell]

 

 

Regarding the last plan with "the right of the slips being a diamond", how do trains get to the second platform from the bottom from the incoming (lower) track?

 

You're right. Silly me trying to look at this while working on a particularly tiresome legal case.

 

So potentially a single slip rather than a double slip. But if you want to respect the norms, I think you have to get rid of slips altogether due to their approx 24" radius.

 

The curved point has a real 30" inner radius which should not be a problem if it is taken in the trailing direction.

[Joseph_Pestell]

I suppose not, in all honesty... I could model an overgrown, disused platform with the track removed I guess?  That would still leave three platforms, and remove some of the associated trackwork issues.  But forgetting that completely and just making it three platforms would still work for what I have in mind.

 

A good point which I hadn't actually considered beyond "ok 4 platforms would look nice" and going from that basis.

 

For a 1980 layout, three operational platforms plus one disused platform could look very good. The track could still be in use for carriage siding but with no facing lead into it (which saves length on your station throat.

[TheSignalEngineer]

Although not Souithern, see if you can find layouts for Watford Junction DC Lines platforms in the late 1980s or Birmingham Moor St as it was from 1969 to 1987. Both done with single leads, 4 and 3 platforms respectively. Sorry I can't help directly with them at the moment, but I will have a look when I can access my files if you can't find them. 

[The Bigbee Line]

Good afternoon,

 

As someone who drools over Southern Region station throats and pointwork I would suggest the following:

 

This is my fag packet version of your original:

 

 

My first suggestion is a 'Readingesque' arrangment with two island platforms.

 

 

If you want three platforms one side can swerve over thus:

 

 

I've added two sidings, which if extended towards the scenic break can give the impression of a 4 track busy looking entry to the throat.  The platform arrangement could be like Holborn Viaduct, with lines for parcels traffic

[cromptonnut]

I'm rapidly coming to the conclusion that I'm not going to get this in 12ft and have enough platform length for a pair of CEPs ... some great ideas here but I just can't seem to quite crack it using off the shelf components.

 

I think it's gonna be 3 platforms.

[maunsel]

I'm rapidly coming to the conclusion that I'm not going to get this in 12ft and have enough platform length for a pair of CEPs ... some great ideas here but I just can't seem to quite crack it using off the shelf components.

 

I think it's gonna be 3 platforms.

 

 

Oh I'm not so sure..........

 

2 x 4CEP = approx 8 feet. 4 feet for the throat.

 

double tracks and a scissors crossing should do it.............

 

 

Eric

[Joseph_Pestell]

Oh I'm not so sure..........

 

2 x 4CEP = approx 8 feet. 4 feet for the throat.

 

double tracks and a scissors crossing should do it.............

 

 

Eric

 

2 x 4CEP is only about 7'. So no real problem there. The issue is getting enough pointwork within a 4' length. It may need 3' radius (medium) points rather than 5' (long).

[cromptonnut]

The problem is with the scissors using four medium points and an SL193 you don't get the 50mm double track spacing which would require a converter board of some description.  The alternative is to extend it up to 16ft and make it a through station, which generates a different selection of problems for me but may be an alternative solution.

[Xerces Fobe2]

Gargle with TCP

[Joseph_Pestell]

The problem is with the scissors using four medium points and an SL193 you don't get the 50mm double track spacing which would require a converter board of some description.  The alternative is to extend it up to 16ft and make it a through station, which generates a different selection of problems for me but may be an alternative solution.

 

Usually a terminus will be shorter than a through station. But this may be an exception.

 

With 7' platforms, you would have 30" each end for throats in an overall 12'. Enough to enable trains to reverse from any of the platforms. There's a bit of a danger of it looking a bit boring but if you box clever with loco spurs etc potential to make it interesting enough.

 

Another solution could be for one of the island platforms to have a bay as well as a loop.

[34theletterbetweenB&D]

I'm rapidly coming to the conclusion that I'm not going to get this in 12ft and have enough platform length for a pair of CEPs ... some great ideas here but I just can't seem to quite crack it using off the shelf components...

Yes you can, if you permit yourself to lightly crop those components; and all with single leads using the large radius point so that both up and down have access to all platforms.

 

To explain: linearly you need five points in series in the 48", which gives two crossovers in series and the splitting point closest the platforms.

 

Inconveniently the five points sum to about 50 5/8". But lose a tad over half an inch from the point blade end of each point and it all goes in 48". You won't be able to use rail joiners on the shortened pieces, because these will foul the point blade tips. Instead solder the rail to brass screws set in the board at appropriate locations.

[The Bigbee Line]

Whilst not OO. Peco have advertised a #6 double slip in code 83. I wonder what radius the slips will equate to? There was a picture in Model Railroader.

Roco do a large radius slip (spoiler is the large flange way). I think it's 10 degrees. Available from Conrad.

[DCB]

The trackwork looks much too complicated, by the 1980s the approach would be singe track and all but two platforms out of use.

Even for the 1960s it is unlikely that all platforms would be available for arrivals, more likely the two bottom platforms would be arrivals and all available for departures though the two top ones  would be the designated departure platforms so there is no real need for a facing crossover as movements will be arrive in the bottom platforms, pull out the stock over the trailing crossover, propel back into one of the top platforms for departure, so most of the pointwork is superfluous.

The trackwork looks much too complicated, by the 1980s the approach would be singe track and all but two platforms out of use.

Even for the 1960s it is unlikely that all platforms would be available for arrivals, more likely the two bottom platforms would be arrivals and all available for departures though the two top ones  would be the designated departure platforms so there is no real need for a facing crossover as movements will be arrive in the bottom platforms, pull out the stock over the trailing crossover, propel back into one of the top platforms for departure, so most of the pointwork is superfluous.