Is the six-foot way going to be realistic fir UK track?

[Andy Reichert]

Is 21 mm for the space between double tracks going to be the norm for UK HO?  I get the feeling that the expectation is not.  I.e How do UK HO modellers feel about sticking with standard Pecoturnouts etc. for crossovers?

 

Andy

[Pandora]

The six foot is a nominal dimension,  for railway track, it is not an absolute dimension,  the minimum value  for seperatin of striaght track can be down to  5 ft 8 inches and vehicles within loading gauge  can pass each other on adjacent lines,  , therefore the figure of 21 mm , 5ft 3 inches in 4mm  is close enough

Edited February 1, 2020 by Pandora

[Joseph_Pestell]

3 hours ago, Andy Reichert said:

Is 21 mm for the space between double tracks going to be the norm for UK HO?  I get the feeling that the expectation is not.  I.e How do UK HO modellers feel about sticking with standard Pecoturnouts etc. for crossovers?

 

Andy

 

Even for 00 the standard Peco geometry gives a 6ft which is oversized and the track can look so much better with the gap reduced by modifying the turnout. So that will be even more the case for UK HO.

But in 00 you can only do this if your minimum curve radius is 4ft as otherwise coaches will collide on curves. Presumably in HO that minimum radius would be 3ft6 but it would be best to lay a bit of test track before committing to it.

[TheQ]

It depends on where you are modelling,  if it's former GWR broad gauge lines,  the 6ft is more like 10ft

If you are modelling the former highland railways Kyle line,  the tracks  were spaced so iirc 16ft wide fishing boats on carried on wagons could pass each other at the dual tracks through the stations.. 

[Joseph_Pestell]

2 minutes ago, TheQ said:

It depends on where you are modelling,  if it's former GWR broad gauge lines,  the 6ft is more like 10ft

If you are modelling the former highland railways Kyle line,  the tracks  were spaced so iirc 16ft wide fishing boats on carried on wagons could pass each other at the dual tracks through the stations.. 

 

That's a railway fact that I have not seen before. Nor indeed had I noticed a very wide "6ft" at those stations.

 

Did they not have boatyards on the west coast of Scotland? Why would one need to transport boats by train?

[Gordon A]

Probably cheaper to move a boat over distance by rail than sailing it.

 

Gordon A

[BMS]

My technique is to vary the spacing between tracks by on the outer rail(s) extending the straight leading into the curve before starting the larger radius curve so that the track spacing on the curve is larger. To my eyes Peco spacing looks wrong. Obviously any points on the straights need the straight part of the curved bit shortened to adopt my spacing!

[TheQ]

6 hours ago, Joseph_Pestell said:

 

That's a railway fact that I have not seen before. Nor indeed had I noticed a very wide "6ft" at those stations.

 

Did they not have boatyards on the west coast of Scotland? Why would one need to transport boats by train?

The intention was to ferry boats from fishing on the west coast to East Coast and back as the boats did  travel did seasonally.  Much quicker than using the Caledonian canal or going over the top.  However having built the line with such clearances, boats got bigger than 16ft wide and there was never the custom to justify it.

 

  I don't know if you noticed it but the unrebuilt platforms on the line are very low at around two ft, that was because the boats would have overhung the platforms as well.  

 

If you think about it each boat at 16ft, would have overhung a maximum width wagon of say 9ft, by 3ft 6inches each side.  So the 6ft would have to be 7ft for touching clearance, maybe just one  more foot for slowly passing through a station. 

[Robert Stokes]

7 hours ago, Joseph_Pestell said:

 

Even for 00 the standard Peco geometry gives a 6ft which is oversized and the track can look so much better with the gap reduced by modifying the turnout. So that will be even more the case for UK HO.

But in 00 you can only do this if your minimum curve radius is 4ft as otherwise coaches will collide on curves.

 

I think this is being too pessimistic. It depends on the coaches you use. I have a minimum radius of 24" with 48mm track centres so the radii of double tracks are 610 and 658mm. Trains of 57' coaches will pass one another without touching. Of  course, in 00 gauge 48mm is still larger than the prototype, which I think should scale to 44mm, but it is better than Peco's nominal 50mm, which if you fit two points as a crossover with insulated joiners is more like 51 or even 52mm.

 

Robert

[Joseph_Pestell]

Fair comment. My figure was for longer coaches.

[stewartingram]

9 hours ago, Gordon A said:

Probably cheaper to move a boat over distance by rail than sailing it.

 

Gordon A

Just like moving a loco by road (nowadays).

 

Stewart

[HSB]

7 hours ago, BMS said:

My technique is to vary the spacing between tracks by on the outer rail(s) extending the straight leading into the curve before starting the larger radius curve so that the track spacing on the curve is larger. To my eyes Peco spacing looks wrong. Obviously any points on the straights need the straight part of the curved bit shortened to adopt my spacing!

I would increase the track spacing through the transition curves.

Edited February 1, 2020 by HSB

[TheSignalEngineer]

15 hours ago, Andy Reichert said:

Is 21 mm for the space between double tracks going to be the norm for UK HO? 

The six-foot should be the minimum space between the outsides of the rails. This is an extract from the MOT Requirements 1950 revision, although the dimension was quoted by the Board of Trade for new construction at least as far back as the 1890s.

 

 

11' 2" track centres is 39.08mm in HO and 44.7mm in OO. 

In terms of clearances in the 12" to the foot world the usual objective was to achieve 18" passing clearance at the worst case of side and end throw. 

I remember when bogie tanks were introduced we couldn't get adequate clearance for the end throw if the connections to the Up and Down Loops outside the Shell depot at Rowley Regis were used at the same time so interlocking was provided to prevent both sets of points being reversed together.

[Grovenor]

16 hours ago, Andy Reichert said:

Is 21 mm for the space between double tracks going to be the norm for UK HO?  I get the feeling that the expectation is not.  I.e How do UK HO modellers feel about sticking with standard Pecoturnouts etc. for crossovers?

 

Andy

The standard spacing for double track in the UK, there are of course exceptions but this will apply to 90% or more of double track, is 6ft between the rails, which comes to 11ft 2 inches between track centres, at scale then 39.1 mm track centres. Even the prototype increases this spacing on sharp curves to allow for end and centre throw of vehicles.

There are very few H0 modellers of the UK prototype, some may use Peco geometry which will then look worse than in 00. Anyone interested in modelling track will aim to get it right.

Rgds

Edited February 1, 2020 by Grovenor

[royaloak]

4 hours ago, TheSignalEngineer said:

 

In terms of clearances in the 12" to the foot world the usual objective was to achieve 18" passing clearance at the worst case of side and end throw. 

They failed miserably at Clapham jn SWML Fast lines then then because if my train was stopped at the 4 car mark on the Down Fast I could put my hand out the cab window (just my hand and not my wrist or any part of my arm) and my fingers would be touching the coach stationary on the Up fast, my hands are quite small for a bloke.

[DCB]

We have been here with OO  quite recently.   16.5mm track gauge plus 24mm "6ft gap" plus 2mm rail top is circa 42mm track centre line spacing in OO  That gives you the 37mm "9ft 2" C1 Mk1 width plus a ft or so gap.   That is for straight track.   Its a bit tight in practice as Hornby etc don't build anything like as accurately  to scale width as they do length I think the 9F is 10ft wide.  10% overscale.   Continental HO and UK OO spacings work pretty much the same. UK Platforms being higher mean UK locos can't be grossly over wide or they n hit the plaforms, low platforms mean in non UK HO it don't matter.

I have tracks down to 44mm, spacing in OO and will use 44mm as a standard where ever possible as the close spacing and ability to shorten crossovers makes it well worthwhile for me.  You do need to widen the spacing for curves, both on model and full size.

If you want to try 21mm gap 39mm track spacing then with Lima UK HO you might get away with it but Continental chassis will be too wide, especially if you fancy a steam Pacific or 4-6-0  and I wouldn't recommend it.   Even 44mm your main line straight track needs to be straight and level.   Not something found on most models, or the stock will rock and roll and sideswipe stock on the other line, Some models by our Asiatic Chums crab along the tracks a few mm out of line out of the box, others won't stay on the shiny bits and the closer track spacing you have the more risk of damage. You have been warned. 

[Joseph_Pestell]

14 hours ago, TheQ said:

The intention was to ferry boats from fishing on the west coast to East Coast and back as the boats did  travel did seasonally.  Much quicker than using the Caledonian canal or going over the top.  However having built the line with such clearances, boats got bigger than 16ft wide and there was never the custom to justify it.

 

  I don't know if you noticed it but the unrebuilt platforms on the line are very low at around two ft, that was because the boats would have overhung the platforms as well.  

 

If you think about it each boat at 16ft, would have overhung a maximum width wagon of say 9ft, by 3ft 6inches each side.  So the 6ft would have to be 7ft for touching clearance, maybe just one  more foot for slowly passing through a station. 

 

Your calculation is wrong there. Never mind the wagon, the boat is overhanging the rail by nearly 6', so the "6 foot" would need to be nearly 13 feet wide if boats were to pass each other. But, from what you say, they would all have been travelling in the same direction so perhaps 9 feet would be enough.

 

This strange traffic must have had quite an impact on gauge for tunnels and bridges as well.

[TheQ]

Err 9ft wide wagon ( most  would be narrower)

Boat width 16ft

16 - 9= 7ft

Divide by 2 sides 

7/2= 3.5 so = 3ft6inches over hang each side... 

 

There are no tunnels on the line,  few bridges over the track. They are wide for Single track but still less than double track,  the only double tracks  on the line  are the passing places at the stations. 

As an example of the clearance here is Ravens rock cutting,  after the track had been realigned further away  from  the rock on the left due to rock falls. There wouldn't have been all those trees then, there are rock faces both sides. The line was built in a cutting round the existing cliff face of Ravens rock. 

 

 

[TheSignalEngineer]

7 hours ago, royaloak said:

They failed miserably at Clapham jn SWML Fast lines then then because if my train was stopped at the 4 car mark on the Down Fast I could put my hand out the cab window (just my hand and not my wrist or any part of my arm) and my fingers would be touching the coach stationary on the Up fast, my hands are quite small for a bloke.

The Southern Region did have a reputation for being a bit tight. The standard for placing TC joints at clearance came about after an incident at East Croydon in the 1970s. A train was right up to the platform end but without the last wheels being on the track circuit through the points. A train crossing to the next line lost a lot of door handles.

[Dungrange]

2 hours ago, TheQ said:

Err 9ft wide wagon ( most  would be narrower)

Boat width 16ft

16 - 9= 7ft

Divide by 2 sides 

7/2= 3.5 so = 3ft6 inches over hang each side... 

 

Yes, that bit's correct, but the 'six foot' isn't measured from the edge of the wagon, it's measured from the outside face of the running rail.  Therefore, you need to replace your nine foot assumed wagon width with the track gauge and the width of two rail heads, so that you are taking your measurements from the correct place.  That is a little over five foot.  16 - 5 = 11.  Divide by 2 = 5' 6" overhang from the outside face of the rail.  Therefore, if you were to have two 16' wide boats passing then you need the 'six foot' to be a minimum of 11 foot wide, plus whatever clearance is considered desirable.  If 18" was generally aimed for, then that means that the 'six foot' would need to be around 12 ' 6".  However, as has been said above, it's unlikely that there would be boat traffic in both directions simultaneously, so if you are only allowing for the passage of boats in one direction and are willing to reduce the clearance to the adjacent 'normal' vehicle (ie one within loading gauge), then it may be possible to get away with something like 8' 6" minimum for your 'six foot'.  That is, half of the boat overhang plus half of a standard six foot would give you half the normal clearance, which might be acceptable if the trains are passing at slow speed.

[TheSignalEngineer]

17 hours ago, royaloak said:

if my train was stopped at the 4 car mark on the Down Fast I could put my hand out the cab window (just my hand and not my wrist or any part of my arm) and my fingers would be touching the coach stationary on the Up fast,

Thinking back, there was a place in the tunnel under St Pancras where we had 4" clearance to the equipment cupboards on the tunnel wall with a 319. I used some battery locos down there once on an engineers train and we had to keep stopping to see if we were going to miss possible obstructions.