Theory of General Minories

[t-b-g]

22 hours ago, Pacific231G said:

And they weren't alone. When Wrenn started marketing their originally export only track, with H0 sleeper spacing, to the British market, they also described it as fine scale for the more discerning modeller  (I think it was also a bit less "universal" than their domestic range so with finer checkrail and crossing clearances)

I know this is not a popular view in fine scale circles but, if you're using much sharper pointwork and curves than prototype, a scale sleeper spacing tends to emphasise that.  I think it's because the number of sleepers is one of our unconscious visual cues to length but it also seems to emphasise the narrowness of OO track.  I've  noticed this even on layouts like Buckingham and Borchester Market . 

 

You mean Buckingham, that well known EM gauge layout?

 

To be fair, the track on Buckingham is very crude by the standards of today but then again, much of the trackwork was built long before code 75 rail was invented. But looking narrow because it is OO isn't one of its failings!

 

The subject of OO track standards has been debated to death on several other threads. The conclusion is that there is no right answer, just a choice of compromise. I am actually with you very much and when I build track in OO I use EM templates, reduced by a proportion of 16.5:18.2, to set out my sleeper spacings and lengths.

 

I think it gives a decent result. I have shown this before, many years ago but this is a OO point built using EM templates shrunken slightly, with just the check rail gaps kept wide enough to allow OO flanges to go through. It was done so long ago I can't remember the check rail gap but it may have been 1.2mm.

 

I was pretty sure I couldn't get OO points looking much better than that.  

[Pacific231G]

1 hour ago, t-b-g said:

 

You mean Buckingham, that well known EM gauge layout?

 

To be fair, the track on Buckingham is very crude by the standards of today but then again, much of the trackwork was built long before code 75 rail was invented. But looking narrow because it is OO isn't one of its failings!

 

The subject of OO track standards has been debated to death on several other threads. The conclusion is that there is no right answer, just a choice of compromise. I am actually with you very much and when I build track in OO I use EM templates, reduced by a proportion of 16.5:18.2, to set out my sleeper spacings and lengths.

 

I think it gives a decent result. I have shown this before, many years ago but this is a OO point built using EM templates shrunken slightly, with just the check rail gaps kept wide enough to allow OO flanges to go through. It was done so long ago I can't remember the check rail gap but it may have been 1.2mm.

 

I was pretty sure I couldn't get OO points looking much better than that.  

good evening Tony

I was vaguely aware that Peter Denny had worked in EM

With both Buckingham (EM) and Borchester Market (OO) and other layouts including Metropolitan Junction (which I saw at ExpoEM in 2016) it was the sleeper spacing emphasising the sharpness of pointwork I was most aware of. I think the narrowness of the gauge in OO simply added to that by making the sleepers appear relatively more spaced out.  For that reason narrow gauge points with the same crossing angle as a standard gauge example also seem sharper- at least  to my eyes they do- because though the points will be in the same proportions so shorter, the lower number of timbers makes their relative shortness also look sharper.  

So, what you're doing by reducing EM templates by 16.5/18.2 is almost (the difference between 18.2 and 18.87 making it not quite) producing  proper scale 3.5mm/ft track rather than trying to make 4mm/ft scale track with the wrong gauge.  That seems a perfectly rational approach to me. I think the reason why Peco has had so much stick for doing the same is that their track is also H0 but with the tighter 600mm sleeper spacing used far earlier in countries like France for fast main lines than Britains traditional sleeper spacing of I think about 750mm (2ft 6inch)

Having tested my modified version of Minories yesterday evening I was watching a repeated  episode of one of the fly on the wall documentaries about the GWR (The Railway or Paddington I'm not sure which) and they were using the rolling track laying factory thing to renew a stretch of track. They were laying concrete sleepers and the commentary said that the machine was laying them exactly 600mm apart. I knew that to be the sleeper spacing used for HS1 (an LGV in all but name and curvature) but not that it's become standard on the rest of Britain's network- if indeed it has.

Edited December 5, 2020 by Pacific231G

[St Enodoc]

5 hours ago, Pacific231G said:

They were laying concrete sleepers and the commentary said that the machine was laying them exactly 600mm apart. I knew that to be the sleeper spacing used for HS1 (an LGV in all but name and curvature) but not that it's become standard on the rest of Britain's network- if indeed it has.

I haven't seen that, David, but it strikes me that "spacing" could mean either a) the distance between sleeper centre lines or b) the gap between two adjacent sleepers. I wonder if they meant b).

[t-b-g]

9 hours ago, Pacific231G said:

good evening Tony

I was vaguely aware that Peter Denny had worked in EM

With both Buckingham (EM) and Borchester Market (OO) and other layouts including Metropolitan Junction (which I saw at ExpoEM in 2016) it was the sleeper spacing emphasising the sharpness of pointwork I was most aware of. I think the narrowness of the gauge in OO simply added to that by making the sleepers appear relatively more spaced out.  For that reason narrow gauge points with the same crossing angle as a standard gauge example also seem sharper- at least  to my eyes they do- because though the points will be in the same proportions so shorter, the lower number of timbers makes their relative shortness also look sharper.  

So, what you're doing by reducing EM templates by 16.5/18.2 is almost (the difference between 18.2 and 18.87 making it not quite) producing  proper scale 3.5mm/ft track rather than trying to make 4mm/ft scale track with the wrong gauge.  That seems a perfectly rational approach to me. I think the reason why Peco has had so much stick for doing the same is that their track is also H0 but with the tighter 600mm sleeper spacing used far earlier in countries like France for fast main lines than Britains traditional sleeper spacing of I think about 750mm (2ft 6inch)

Having tested my modified version of Minories yesterday evening I was watching a repeated  episode of one of the fly on the wall documentaries about the GWR (The Railway or Paddington I'm not sure which) and they were using the rolling track laying factory thing to renew a stretch of track. They were laying concrete sleepers and the commentary said that the machine was laying them exactly 600mm apart. I knew that to be the sleeper spacing used for HS1 (an LGV in all but name and curvature) but not that it's become standard on the rest of Britain's network- if indeed it has.

 

I think we both have the same basic idea about track. It is all about the proportions.

 

Having proper 4mm scale sleeper sizes and spacing works well for P4 and for more modern EM.

 

In 4mm scale, 16.5mm, having what is in effect HO track preserves the proportions better than having correct 4mm sleeping with narrow rails.

 

I know not everybody agrees so I don't make a big thing of it or say it is what people should do. Just that it is what I prefer.

 

OO has to be a compromise somewhere and it is down to the individual where that compromise is made. There is a slight benefit in that an HO point is 7/8ths the length of a OO one so saves you a little length when that is critical.

Edited December 5, 2020 by t-b-g
Spelling

[Zomboid]

32 minutes ago, t-b-g said:

In 4mm scale, 16.5mm, having what is in effect HO track preserves the proportions better than having correct 4mm sleeping with narrow rails

I agree, I find that correct sleeper spacing only serves to emphasise the narrow gauge.

 

Having all the track to one scale looks better to me than having the length to 1:76 and width at 1:87. The way HO track doesn't quite match the OO trains is less of an issue for me.

[RJS1977]

4 minutes ago, Zomboid said:

I agree, I find that correct sleeper spacing only serves to emphasise the narrow gauge.

 

Having all the track to one scale looks better to me than having the length to 1:76 and width at 1:87. The way HO track doesn't quite match the OO trains is less of an issue for me.

 Let's not forget of course that track on a layout is often seen without trains on it - particularly between stations. Whilst perhaps not appertaining to an intensively-worked layout like Minories, many layouts may well have significant sections of track where trains are seen less than 50% of the time.

[Pacific231G]

4 hours ago, St Enodoc said:

I haven't seen that, David, but it strikes me that "spacing" could mean either a) the distance between sleeper centre lines or b) the gap between two adjacent sleepers. I wonder if they meant b).

Good morning

No. they specifically stated that it was 60cms centre to centre and it clearly was. I don't know if that spacing applies specifically to concrete sleepers.

Edited December 5, 2020 by Pacific231G

[Compound2632]

Our expectations are so conditioned by Peco Streamline and the set-track systems that follow suit that prototypical sleeper spacing, especially on older track, looks odd to us (even if at H0 scale spacing). It requires an effort of will and imagination...

[Zomboid]

We also normally see real track at vastly different angles to that which we view model track. The viewing angle (particularly along the track) from the platforms, or a bridge, or a level crossing foreshortens the gaps, so that when you see model track from some kind of helicopter, actual scale spacing looks much wider.

[Pacific231G]

18 minutes ago, Compound2632 said:

Our expectations are so conditioned by Peco Streamline and the set-track systems that follow suit that prototypical sleeper spacing, especially on older track, looks odd to us (even if at H0 scale spacing). It requires an effort of will and imagination...

Good afternoon Stephen.

Perception is obviously very subjective, so can't really be reduced to objective mathematical formulae, but I think that what makes sleepering spaced at 1:76 scale look odd is mostly the fact that our curves and crossing angles are almost invariably far tighter than would be found in the same situation in real life*. The number of sleepers is a major cue for our perception of the length of trackwork and therefore the curve through it.

 

 

*Because they generally have far more room to play with than we do,  I had a look at what was generally available for the American market and compared it with a British military railway manual from 1940 (like model track manufacturers the military standardised on as few types as possible. if they were going to have to be transported  overseas they didn't want to be messing around with umpteen variations of frogs and switches.)

 

So, in Peco's code 83 range (considered a premium product in the US) there are #5, #6 and #8 left and right hand turnouts (corresponding to crossing angles of 11.4, 9.5, and 7.1 degrees respectively)  while the "other" premium RTL brand, Micro Engineering, offers #5 and #6 L&R hand turouts in code 83. In code 70 - clearly aimed at the more fine scale modeller- they only offer a #6 turnout . Interestingly, in N scale- where there's obvously more space for prototypical length turnouts- they still only offer a  #6 turnout and their components for hand laying turnouts in both N and H0 only include a #6 frog.   So, for, "serious"  American modellers a turnout with a  #6 frog  is seen as a good general purpose turnout for all but high speed junctions.  (by comparison, a #5 corresponds roughly to a typical three foot radius turnout as offered by  SMP etc.) By comparison even C&L Finescale only offer common crossings in 4mm scale (OO,EM or P4) from no. 5 to no.9 so a no. 9 (1in 9) crossing angle can be taken as the largest crossing number comonly used by FS modellers. 

Now compare that with the turnouts used by the Britsh military in the field. These were standardised on a no. 6, no.8 and no. 12 but "The No.6 will only be used in very congested areas such as docks and where small shunting engines usually operate ; the no. 8 is the standard for general yard and station work; the No. 12 will only be used in places where high speeds are expected"  A typical no 8 turnout is 80 ft long overall.

So, even finescale modellers are using turnouts about 2/3 the length of those laid even by the military "in the field". 

 

[Siberian Snooper]

If I remember correctly, the Peco range was originally for the North American market and uses their track geometry.  When I have been over there, their ties (sleepers) are about half the width of ours and at closer spacings than ours, whether there has been a change in their track building methods, I don't know, not having taken much interest in overseas trackwork.

 

 

[Keith Addenbrooke]

3 hours ago, Pacific231G said:

Good afternoon Stephen.

Perception is obviously very subjective, so can't really be reduced to objective mathematical formulae, but I think that what makes sleepering spaced at 1:76 scale look odd is mostly the fact that our curves and crossing angles are almost invariably far tighter than would be found in the same situation in real life*. The number of sleepers is a major cue for our perception of the length of trackwork and therefore the curve through it.

 

 

*Because they generally have far more room to play with than we do,  I had a look at what was generally available for the American market and compared it with a British military railway manual from 1940 (like model track manufacturers the military standardised on as few types as possible. if they were going to have to be transported  overseas they didn't want to be messing around with umpteen variations of frogs and switches.)

 

So, in Peco's code 83 range (considered a premium product in the US) there are #5, #6 and #8 left and right hand turnouts (corresponding to crossing angles of 11.4, 9.5, and 7.1 degrees respectively)  while the "other" premium RTL brand, Micro Engineering, offers #5 and #6 L&R hand turouts in code 83. In code 70 - clearly aimed at the more fine scale modeller- they only offer a #6 turnout . Interestingly, in N scale- where there's obvously more space for prototypical length turnouts- they still only offer a  #6 turnout and their components for hand laying turnouts in both N and H0 only include a #6 frog.   So, for, "serious"  American modellers a turnout with a  #6 frog  is seen as a good general purpose turnout for all but high speed junctions.  (by comparison, a #5 corresponds roughly to a typical three foot radius turnout as offered by  SMP etc.) By comparison even C&L Finescale only offer common crossings in 4mm scale (OO,EM or P4) from no. 5 to no.9 so a no. 9 (1in 9) crossing angle can be taken as the largest crossing number comonly used by FS modellers. 

Now compare that with the turnouts used by the Britsh military in the field. These were standardised on a no. 6, no.8 and no. 12 but "The No.6 will only be used in very congested areas such as docks and where small shunting engines usually operate ; the no. 8 is the standard for general yard and station work; the No. 12 will only be used in places where high speeds are expected"  A typical no 8 turnout is 80 ft long overall.

So, even finescale modellers are using turnouts about 2/3 the length of those laid even by the military "in the field". 

 

Fascinating, thank you.
 

I was re-reading Linn H. Westcott’s “101 Track Plans” (Kalmbach) the other day.  First published in 1956, the plans mostly use #4 or #6 switches (just one: a ‘dream layout’ idea has #8 switches as a minimum).  In discussing #6 switches v #8 switches, the accompanying text alongside the plans notes that, while #8 switches ‘look nice’ they are 50% longer than #6’s, and #6 switches are deemed suitable even for operating at speed.  
 

It is a different application (“model : model” not “model: prototype”) from an earlier era of the idea that turnouts 2/3rds the length that might be used can be recommended.

Edited December 5, 2020 by Keith Addenbrooke

[Joseph_Pestell]

9 minutes ago, Siberian Snooper said:

If I remember correctly, the Peco range was originally for the North American market and uses their track geometry.  When I have been over there, their ties (sleepers) are about half the width of ours and at closer spacings than ours, whether there has been a change in their track building methods, I don't know, not having taken much interest in overseas trackwork.

 

 

 

Absolutely not. Streamline was designed as a compromise suitable for Europe and the UK. I suspect that M. Fournereau played a big part in it.

US trackwork is based on angles (#4, #5 etc) rather than radius, both real and prototype as is the newer Peco code 83.

[Pacific231G]

20 hours ago, Siberian Snooper said:

If I remember correctly, the Peco range was originally for the North American market and uses their track geometry.  When I have been over there, their ties (sleepers) are about half the width of ours and at closer spacings than ours, whether there has been a change in their track building methods, I don't know, not having taken much interest in overseas trackwork.

 

 

British and European sleepers are usually 10" wide, American ties commonly  9" wide. 

US tie spacing is normally 20-21" centre to centre, but that can rise to 21-24" on lighter slow speed secondary lines.  In Europe (well France certainly) sleeper spacing on main lines in normally 60cms (23.6") but generally wider on secondary lines and sidings especially for older track . Standard British spacing is/was 30" but seems to have moved to 60 cms for high speed and modern concrete sleeepered main line track. 

 

I very slightly disagree with Joseph that Streamline was designed as a compromise between the UK and continental European markets though it is a compromise for UK 4mm scale as is all OO track- it's just a question of which compromise you choose.  Streamline's sleepers are pretty well spot on for French FB mainline track in 1:87 (H0) scale at 600mm. centre to centre spacing. With some exceptions, standard sleeper sizes are though the same in most of Europe so the sleeper dimensions if not their spacing are also correct for British FB track IN 1:87 scale. OO is a compromise anyway so Sydney Pritchard may have figured that if he was going to produce track to 1:87 scale gauge for models of both 1:76 and 1:87 scale he might as well bite the bullet and produce H0 scale track.

 

French aiguillage (pointwork) also seems to be closer to British than to say German practice and all are rather different from American practice. 

 

US turnout geometetry does seem to be rather different from ours though, as everywhere, it's based on the crossing angle. quoted as a number in Britain and America  such as no. 7  or #7 for 1:7 but as a tangent such as Tg  0.13 or 1/7  in France (they used to be quoted there by some railways in degrees) . the tangent is in principle the reciprocal of the ratio though there may be a minor difference in how it's measured at the frog/crossing (right angle or isosceles triangle) 

 

One difference seems to be that ,in N. America, the frog angle pretty well defines the length of a turnout with a straight frog and an easement curve to the switch. In Europe, probably because pointwork is often more concentrated, it's quite possible to have longer and shorter  versions  of turnouts with the same crossing angle by using a different lead and adjusting the curvature between the switch and the crossing - what Peco does to get short and medium versions of turnouts with the same 12 degree crossing angle.

 

Sydney Pritchard certainly knew J. Fournereau and there does seem to be an ongoing relationship between the two family companies but, as a  model manufacturer, Fournereau had focussed more on locos and rolling stock  than track. He may though have supplied Pritchard with track templates. Unlike Peco, Fournereau gradually made publishing his main business activity and after the war Fournereau Modelisme, which had focussed on 0 scale, gradually disappeared.   

 

Though Streamline is scale H0 track with 60cm sleeper spacing, it's possible that Pritchard  figured- correctly- that he could sell it into the American market as well as to the rest of Europe even though, until their code 83 line, they'd never used NMRA standards. The sturdiness and ease of use of Streamline seems to have won over a fair number of modellers there even though it differs considerably from American practice. As wells as code 83 line They now also produce 10.5 mm gauge H0n3 track aimed primarily at the American market.

 

Though French modellers also use Tillig and Roco (as well as proprietary brands like Marklin or Hornby) the majority do seem to use Peco track and, despite the sleepers being slightly wide for H0 scale* , their new bullhead range seems to be selling well there.  

 

*I've been told that Peco bullhead is pretty well spot on in H0 scale for the spacing and the wider softwood pine sleepers used by the Midi for its double champignon rail but I think that really is just a coincidence.

Edited December 6, 2020 by Pacific231G
spelling and typos

[Pacific231G]

Back to Minories

This is what my modified version looks like laid out with track  (fairly crudely the main lines at the right are meant to be parallel)

A test train, pushed along by hand (which feels a bit like second childood) snakes reasonably elegantly over the six routes. 

 

From toe to toe the actual throat pointwork occupies 36 inches so should fit comfortably on a metre long board with room for an inch and a half of pcb reinforced track to cross the board joints at each end. The platform tracks will make a gentle curve to horizontal (as per the plan) after a couple of inches of straight track from the board joint. That should give me an an absolute maximum train length of five feet which, with the H0 stock I'm using, is very comfortably enough for a four coach train headed by a Pacific or Mikado  and just about long enough for four coaches and a fourgon (four wheel brake van) I am though also looking at a possible alternative single track throat that wouldn't allow a much longer train (maybe five coaches with no fourgon) but would be less tight all round. I think though that might not provide the urban spur  terminus feel I 'd rather like to have.   

[t-b-g]

2 minutes ago, Pacific231G said:

Back to Minories

This is what my modified version looks like laid out with track  (fairly crudely the main lines at the right are meant to be parallel)

A test train, pushed along by hand (which feels a bit like second childood) snakes reasonably elegantly over the six routes. 

 

From toe to toe the actual throat pointwork occupies 36 inches so should fit comfortably on a metre long board with room for an inch and a half of pcb reinforced track to cross the board joints at each end. The platform tracks will make a gentle curve to horizontal (as per the plan) after a couple of inches of straight track from the board joint. That should give me an an absolute maximum train length of five feet which, with the H0 stock I'm using, is very comfortably enough for a four coach train headed by a Pacific or Mikado  and just about long enough for four coaches and a fourgon (four wheel brake van) I am though also looking at a possible alternative single track throat that wouldn't allow a much longer train (maybe five coaches with no fourgon) but would be less tight all round. I think though that might not provide the urban spur  terminus feel I 'd rather like to have.   

 

That looks nicely balanced and laid out.

 

Sometimes, there is a time when the planning has to stop and the building starts. You may well have reached that point!

 

I don't think you will come up with anything better, no matter how long you spend trying.

[Keith Addenbrooke]

31 minutes ago, t-b-g said:

 

That looks nicely balanced and laid out.

 

Sometimes, there is a time when the planning has to stop and the building starts. You may well have reached that point!

 

I don't think you will come up with anything better, no matter how long you spend trying.

Good advice as always.

(Confession: I clicked ‘like’ quickly so I see @t-b-g’s reputation points tip from 10,999 to 11,000: must be Sunday evening .  I know it’s not why we do this - but well deserved nonetheless).

Edited December 6, 2020 by Keith Addenbrooke

[t-b-g]

2 hours ago, Keith Addenbrooke said:

Good advice as always.

(Confession: I clicked ‘like’ quickly so I see @t-b-g’s reputation points tip from 10,999 to 11,000: must be Sunday evening .  I know it’s not why we do this - but well deserved nonetheless).

 

That sounds like a lot but I have to confess that I have never heard of a reputation point and have little idea what that means!

 

But thanks anyway!

[RJS1977]

5 minutes ago, t-b-g said:

 

That sounds like a lot but I have to confess that I have never heard of a reputation point and have little idea what that means!

 

But thanks anyway!

 

It's the number with the green plus next to it underneath your avatar to the left of each post, and presumably it gives a count of how many positive reactions your posts have received.

[t-b-g]

1 minute ago, RJS1977 said:

 

It's the number with the green plus next to it underneath your avatar to the left of each post, and presumably it gives a count of how many positive reactions your posts have received.

 

I had never even noticed it before so thanks for explaining.

[Pacific231G]

4 hours ago, t-b-g said:

 

That looks nicely balanced and laid out.

 

Sometimes, there is a time when the planning has to stop and the building starts. You may well have reached that point!

 

I don't think you will come up with anything better, no matter how long you spend trying.

Thanks Tony and I agree so far as trying to develop Minories any further is concerned.

I really got to that point quite some time ago but wanted to take my H0m layout further first. Seeing if it really is possible to improve on Minories has also been something of an intellectual, almost a mathematical, challenge.  The constraints I was working with included trying to do it entirely with medium points to get as much train length as possible. With a four metre long room length a few inches really do make a difference. In  the end I decided to sacrifice the odd two inches (which only makes a one inch difference to train length on a terminus to fiddle yard set up)  by using a long turnout as the final exit point.

Working in European H0, the coaches are actually narrower than those to British loading gauge in 4mm scale so the relative displacement and apparent buffer locking is that much greater and more noticeable, though it's the relative movement of the corridor connection "bellows" that is most obvious, they were actually narrower in reality.  This plan probably would therefore work with 4mm/ft scale stock but I haven't tested it with any,

With the original Minories plan there is another solution to the problem of the excessive displacement over the two back to back middle points which is an operational one. You simply work it with platform one as departures only and the ECS movements from the other two platforms are always made via the departures line. That way a train would never actually travel over that route That does though run counter to CJF's conception of a busy inner city commuter station as all plaforms would then be both arrival and departure.

 

The next challenge is how to deal with the timbering of Peco points on complex pointwork. Cutting timbers to the chairs is OK with scrap points for trial set ups but real track needs to be properly supported.

Edited December 6, 2020 by Pacific231G

[t-b-g]

7 minutes ago, Pacific231G said:

Thanks Tony and I agree so far as trying to develop Minories any further is concerned.

I really got to that point quite some time ago but wanted to take my H0m layout further first. Seeing if it really is possible to improve on Minories has also been something of an intellectual, almost a mathematical, challenge.  The constraints I was working with included trying to do it entirely with medium points to get as much train length as possible. With a four metre long room length a few inches really do make a difference. In  the end I decided to sacrifice the odd two inches (which only makes a one inch difference to train length on a terminus to fiddle yard set up)  by using a long turnout as the final exit point.

Working in European H0, the coaches are actually narrower than those to British loading gauge in 4mm scale so the relative displacement and apparent buffer locking is that much greater and more noticeable, though it's the relative movement of the corridor connection "bellows" that is most obvious, they were actually narrower in reality.  This plan probably would therefore work with 4mm/ft scale stock but I haven't tested it with any,

With the original Minories plan there is another solution to the problem of the excessive displacement over the two back to back middle points which is an operational one. You simply work it with platform one as departures only and the ECS movements from the other two platforms are always made via the departures line. That way a train would never actually travel over that route That does though run counter to CJF's conception of a busy inner city commuter station as all plaforms would then be both arrival and departure.

 

The next challenge is how to deal with the timbering of Peco points on complex pointwork. Cutting timbers to the chairs is OK with scrap points for trial set ups but real track needs to be properly supported.

 

I have carried out very similar exercises several times over the years, tweaking the plan here and there. A few layouts have resulted, including the present effort which has the station throat only two points long, allowing great long sweeping curves which suit corridor stock better.

 

I don't know if it was ever written down but I wonder if CJF was aware of the problems caused by the overhang on a corridor carriage, which is why he suggested it as a suburban type service, where non corridor stock was more likely to be used. It does away with that problem easily! 

[KeithMacdonald]

2 hours ago, t-b-g said:

 

That sounds like a lot but I have to confess that I have never heard of a reputation point and have little idea what that means!

 

But thanks anyway!

 

11010 now.

One more and you will be the palindromic RMWeb member of the day.

[Keith Addenbrooke]

8 hours ago, t-b-g said:

I don't know if it was ever written down but I wonder if CJF was aware of the problems caused by the overhang on a corridor carriage, which is why he suggested it as a suburban type service, where non corridor stock was more likely to be used. It does away with that problem easily! 

I haven’t read / re-reread all 73 pages of this thread, but I don’t recall that being mentioned previously - there would still be a ‘snaking effect’ for trains passing through the S-curve, but perhaps the answer to this particular point has been there all along, exactly as you describe.

 

I suppose it’s possible that CJF, starting with non-corridor suburban stock, didn’t worry about a problem that wasn’t there for him (if that makes sense), but the outcome is the same.

[KeithMacdonald]

On 30/11/2020 at 16:57, Pacific231G said:

Hi Keith

I had a play around with this in Anyrail and came up with this . It's on  25cm grid.

 

I've not tried to match your curves beyond the throat each side exactly but that could be done quite easily and the throat is the same length . This  is made up entirely of left and right medium length turnouts. Though you have to look quite carefully to convince your eyes, there are no unseparated reverse curves and the only reverse curve of any type is the one into the lower platform. That has a radius of 447 cm (14'8")  so won't cause any problems. 

The equivalent of your piece of track marked in red now has a minimum radius of 103 cm (40") so still a significantly shallower curve than the turnouts albeit tighter than your original. With no reverse curves there'll be no buffer locking and the passengers might even be able to use the corridor connections without falling to their doom. .

 

 

@Pacific231G - many thanks for that. To my eyes, it's the best design yet.