Dual Gauge

[Dave Cooper]

Hi All - a bit of help from the experts please,

My diorama (working) is currently a mix of standard gauge and narrow gauge (Peco 00, 75 and N gauge, 80). Due to baseboard constraints, the operating scope is limited, therefore, I'm wondering about going dual gauge on the SG part - this is before adding an extension /fiddle yard baseboard.

I'm fairly confident about adding a third rail (which would be just off centre of the 00 track) except for point work - just two at present - which would cause some head scratching ! 

A few questions :

1. Would this look silly ?
2. Is it feasible to modify the existing Peco Electrofrog points to take a third rail ?
3. Would a standard 'N' track gauge also serve to modify the points ?
4. To make life easier, I could restrict NG access to only certain SG roads (eg by excluding access to the engine shed road, I would only need to modify the 'straight through' part of a point ?)

Hope this makes sense !
Dave

[Hobby]

You are aware that Tillig do Dual gauge track, aren't you?! You could look at their examples for what they look like.

https://www.tillig.com/Nenngroesse_H0e_Gleissysteme.html

[Dave Cooper]

I had a feeling someone did - just couldn't remember the name !

Nice looking track, a bit pricey but then I suppose this reflects the work involved...

Thanks

[Robin Webster]

Dave, have you thought of scratch building one for layout. I was looking at a peco OO switch after your post and i think it will be tough job. Funny a few weeks back i thinking of making one for myself except in broad gauge.I just haven't been too motivated of late. I will give it a try at some point.
Robin.

[JulienW]

To answer those in order Dave:

1. No. Such things did exist in real life and whilst I think it was more common elsewhere there were a couple of bits of dual gauge in the UK, one example that comes to mind were the dual gauge W&LLR / GWR sidings in Welshpool around the cattle market (which I think still exist somewhere in the redeveloped town center) and a couple of 3' / 5'3" sections in Ireland.

2. Yes and no. Staring with a 9 mm gauge point (N or 009) and if the standard gauge is  only going one way and it is 'outside' the narrow gauge - so it's not crossing any narrow gauge rails - that will be fairly straight forward to do. The problem comes when the rails need to cross because that needs a frog to be constructed, so laying a 3rd rail for the narrow gauge between the rails on a standard gauge point becomes harder as whichever way it goes through the point it will need to cross one or other of the standard gauge ones.

3. The only difference between an N and 009 point is the size and spacing of the sleepers. In some respects if you were cutting up a 9 mm gauge point then the smaller sleepers may be easier to fit into the spaces between the sleepers of the OO one.

4. That's probably the right approach. In real life laying a 3rd rail adds to the cost of building the track and also to the costs of maintenance - that's part of the reason why Statfold Barn Railway got rid of their 2'6" gauge 3rd rail as the extra costs didn't justify the use it got - so the dual gauge would only be put in where it was needed. As an example whilst a single road shed long enough for 2 locos might be dual gauge a more likely scenario is that a 2 road shed would be built with one narrow gauge bay and one standard gauge bay, each taking a single loco. It also means that you don't have to get one loco out of the way to get to the one you need.

I think that if you can find some then some track gauges for both 9 mm and 16.5 mm gauges would be useful so that any rails that you are adding to to ready to lay track can be set accurately.

The other way to go would be to hand build the dual gauge track. The track gauges will help with this and the usual method is to solder the rails - stripped from second hand would be fairly straight forward - to copper covered sleepers. Use OO ones for mixed-gauge track OO / 009 track, but as specific '009' ones may be harder to find you could use the OO ones cut down (just like the modern preservationists!) but for my own 009 track building I've used pre-cut TT sleepers.

The advantage of building your own is that you will not be limiting your track layout to what Peco, etc. produce, so if you wanted an unequal Y point with dual gauge on one side only you can build it as that's something that Peco will never do!

One thing to mention is that the "code" of the rail is its height in thousandth of an inch, so that there will be 5 thou height difference between the code 75 and code 80 rails if these were laid on the same sleeper. It's just over 0.1 mm so you might be able to get away with it , but it's possible that poor running may result if the rail heads are not level. If you were cutting up the plastic track to make dual gauge it might be worth getting some 5 thou plastic sheet to pack under sleepers of the code 75 rail(s) might be useful.

[Hobby]

Nice looking track, a bit pricey but then I suppose this reflects the work involved...

More likely the very limited market! ;)

[Hobby]

Just some general comments to add to what Julien said. Adding an additional rail to plain OO 16.5mm gauge track wouldn't be too much of an issue, I'd tend to cut out a sleeper every inch or so and replace it with a copper clad one and solder the third rail to that, easy and would look fine.

I'm not sure about the points, though. Personally I'd either make them from scratch using the images of the Tillig points to show you  the details or I'd bite the bullet and buy the Tilling ones. Modifying plain RTR points seems an awful lot of work and prone to disaster compared with the other two alternatives. The amount of cutting you'd have to do on a RTR point to make it suitable as a dual gauge point would also weaken the structure. I'm sure building it from scratch would be easier.

The only example I've seen where the NG and SG share a loco shed I've seen (Frydlant in the Czech Republic) the shed does indeed have two separate roads, one SG and one NG, they do not have dual gauge. One reason would seem to be that it would restrict access to the undersides of the SG locos from the pit.

[andy1878]

Not strictly the same: The Ravenglass and Eskdale once had the Standard gauge straddling the narrow gauge. So 4 parallel rails.
Never seen a photo of now the two met and separated, there must have been crossings of some sort.

[Hobby]

Metre gauge Baie de Somme still has... In a few words... Don't go there!

CFBS mixed gauge pointwork, St.Valery Ville 28.05.11 by Phil, on Flickr


Normally when this happens (NG separate in middle of SG) is is normally to facilitate the NG locos being able to pull SG wagons, you can do it with offset (3 rail) but it is more difficult as couplings have to be offset whereas if the track is laid out as 4 rail centre couplings suffice. I think I remember seeing 750 or 760mm with offset couplers somewhere in Europe. One other place you can have 4 rails is where rollboks are in use where the NG goes down the centre of SG track but at a slightly lower level.

[Peter Boulter]

Didcot Railway Centre has some mixed broad & standard (or should that be narrow?) gauge trackwork.

[Tom Haythornthwaite]

I must warn you that Peco rolling stock cannot navigate Tillig points. 

Looking at their Art-Nr. 85181...



...and imagining a wagon approaching from the left, the flanges of the right-hand wheels will hit and ride up over the pointed end of that interrupted broad gauge rail. 

Also the narrow gauge arm extends straight for a few centimetres which needs accommodating or modifying.

I got rid of my Tillig stuff and am working on my own four-track solutions.

[Hobby]

Must be something to do with Peco stock, then... New or old stuff? I've seen a couple of layouts using them and without any issues, but they were German and Austrian layouts so using the Continental stock. The checkrail on the other side should stop the flange hitting the SG rail. Personally I'd modify the plain SG flexi track as I said before and build the points using the Tillig examples as examples of where to put check rails, etc. I just think 4 rail (I assume you mean that rather than four "track" which is something else) is just complicating things. Prototype-wise it is very rare compared with three rail.

[Alan Feldon]

I have triple gauge on my layout (9/12/16.5) Its not that difficult if you take your time and think logically .
I have used pcb sleepers and soldered all my own track but dependant upon how much mixed track you want its possible to cheat.
For instance you want a length of standard gauge track with 9mm sharing one rail .
Lets assume you want the 9mm coming off to the right .Then on the straight lay 00 gauge pcb sleepers upto where the ng branches off . Start with the common rail , then solder the rail for 9mm gauge and then the outer rail for SG .
Have the 9mm lead up to an 009 point which takes care of the line branching off to the right .Then using the straight frog rail for the SG , continue the top SG rail on .This does leave you with the stub of ng straight poking slightly into the SG section but does overcome the worry of ng stock not being able to traverse the frog as it will be going over a normal 009 point .
It gets far more complicated it you want the ng rail to enter one side and depart the other !
The only reason for this kind of track layout is either a goods siding on a pier where the width is limited or say a station where there is a narrow entry/exit so the permanent way has to be share d.
Be warned if you do go ahead the dual gauge track will limit what can be run at any one time .

[B.Meldon]

We tried the tillig track but it was no good for us.
The problems we had were as follows:

1. The dead frog caused some NG four wheel locos to stral at slow speeds. (Just like any deadfrog point does.)
2. The frog gap was too big for many of the NG items that just dropped down the gap.
2. The SG flangeways were too small and not deep enough for many of the SG locos and rolling stock we wanted to use.
3. The size of the rail and the height from the board to the top of the rail was not the same as Peco 009 track or Peco SG track.

In the end we made our own dual gauge track and points.

We used Peco SG track, rails and sleepers so we had the clearance we needed for all the SG items we wanted to run. This required some adjustments to the trackbed, so that the NG rail head is the same height as the Peco SG rails at the joint. We found it better not to use fishplates at all at the joints, but with the track securely pinned down this has not caused any issues in over 15 years of use:



For the dual gauge track we made this out of Peco 00 track. the third rail was made using Peco 00 rail with 00 sleapers cut in half. every other sleaper on the 00 track was cut away to give room for the third rail sleapers. As was use a 1/4 (6mm) plywood trackbed it was easy to pin the sleapers down. Once the ballast is added and it is all painted rust colour the extra track pins and any tiny gaps where the sleepers are cut are hardly noticable:



The point was another problem altogether. We tried various fixed frog arrangements both RTR and home built, using 00 rail, and a combination of 00 and 009 rail but none would give faultless slow running. It would have been possible to build it all with 009 rail and then only use fine scale 00 wheel flanges, but that would have been too restrictive on the standard gauge items we could use and also every other SG point on what is a very big layout would have to be built to the same fine standard as normal Peco 00 points would cause fine scale 00 wheels to de-rail!  In the end we made the point from scratch using copper clad sleepers and 00 rail but with a moving frog, much like that used in the Welsh quarry stub points. The dual gauge point also has a moving blade that is linked to the moving frog. This has proved to work very well indeed over the years. It is operated with a solenoid type point motor. Here is a photo of the point, it is set to the NG, the checkrails are not needed and have only been added for looks:



In conclusion you will have to comprimise is some way:
If you use the Tillig RTR track this may well give you running problems with 009 locos stalling at slow speed and some SG items not fiting through the checkrails.
If you build the dual gauge point your self using 009 rail you will have to use only fine scale 00 wheels.
The way we did it gives very good running and reliability but is complicated and perhaps not prototyopcal for your setting.

(There is an example of exactly this type of dual gauge points in use in East Germany, or there was in the 1990's, but we only found this  after we built the point!)

[Robin Webster]

Very nice work on the turnout /switch and track.
Robin.