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So I am risk of confusing myself even more. I have found a couple of photographs that appear to show some sort of bar, but the other side of the point mechanism, i.e. 'inside' the point itself. Assuming that this is right (and not some sort of optical illusion) a bar in that position, adjacent to a switch blade, must perform a different function?

 

Probably a fouling bar, it prevents conflicting movements that may strike the vehicle standing on it.

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So I am risk of confusing myself even more. I have found a couple of photographs that appear to show some sort of bar, but the other side of the point mechanism, i.e. 'inside' the point itself. Assuming that this is right (and not some sort of optical illusion) a bar in that position, adjacent to a switch blade, must perform a different function?  

Locking bars were sometimes fitted on the switches where fitting them on the immediate approach to the points was not possible. It serves the same purpose.

Fouling bars were different and usually close to the clearance limits on the converging side of a turnout. Used to confirm no vehicles were standing foul before the points could be changed.

 

I would suggest, if you want more definitive answers, that you mention the location of the diagrams and phhotos you are discussing and either provide links or upload them.

Regards

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So I am risk of confusing myself even more. I have found a couple of photographs that appear to show some sort of bar, but the other side of the point mechanism, i.e. 'inside' the point itself. Assuming that this is right (and not some sort of optical illusion) a bar in that position, adjacent to a switch blade, must perform a different function?  

 

Point lock(ing) bars could be sited in a variety of positions.  The obvious one is in rear of the switch toes and probably between the protecting signal and the toe of the point but often the bar would be 'inside the point alongside the switch rails and on the inside of them but also bars could be outside the running rail.

 

This page of Jan Ford's very informative site show two ways of doing it -

 

https://janfordsworld.blogspot.co.uk/2014_09_18_archive.html

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Locking bars were sometimes fitted on the switches where fitting them on the immediate approach to the points was not possible. It serves the same purpose.

Fouling bars were different and usually close to the clearance limits on the converging side of a turnout. Used to confirm no vehicles were standing foul before the points could be changed.

 

I would suggest, if you want more definitive answers, that you mention the location of the diagrams and phhotos you are discussing and either provide links or upload them.

Regards

 

 

 

Venn Cross, on the Taunton-Barnstaple line. Here is one of the points, with what appears to be a bar on the right, 'inside' the point.

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Yes, FPL bar along the inside of the switch, and you can see the joint from the bar to the scalebeam crank which operates the FPL itself. 

 

Even more worth a mention is that magnificent signal. GWR centre pivot arm but the spectacle plate mounted separately lower down the post. Looks as if when the arm rotates anti-clockwise to 'OFF' the spectacle plate rotates clockwise.

 

You should post that picture in the prototype for everything thread.

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Yes, FPL bar along the inside of the switch, and you can see the joint from the bar to the scalebeam crank which operates the FPL itself. 

 

Even more worth a mention is that magnificent signal. GWR centre pivot arm but the spectacle plate mounted separately lower down the post. Looks as if when the arm rotates anti-clockwise to 'OFF' the spectacle plate rotates clockwise.

 

You should post that picture in the prototype for everything thread.

 

It was arranged like that for sighting from the tunnel mouth but even then it was a very unusual arrangement probably also prompted by the steep (1in58) rising gradient through the tunnel towards this signal.  

 

Somebody was also very clever when they planned the single line crossing loop at Venn Cross as it had trap points at the departure end of both loops thus obviating the need to stop/check approaching trains at the Home Signals when crossing another train, particularly important with the steep rising gradient through the tunnel.

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Rule 39a exemption was used in a number of places in similar circumstances. At Rowley Regis it applied to the Up Home, where the signal was on leaving Old Hill Tunnel. Trains were banked up there and if the signal was not cleared the banker was still in the tunnel and pushing as he couldn't see the signal. One night the signalman forgot to clear the signal, the train engine slammed the brakes on and the banker didn't, resulting in a large pile of scrap wagons in the cutting.

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I had my copy of the 1960 Exeter District Sectional appendix out the other day, and an entry for Venn Cross caught my eye: “The provisions of Rule 39(a) do not apply to the operation of the Down Home signal so far as Down Freight and Down Passenger trains, booked to stop at Venn Cross, are concerned.” I guess they really did not want to stop trains in that tunnel / on that gradient. Looking at the recently published Lightmoor book on the Taunton - Barnstaple, the signal box diagrams show that all the loops on this line had traps at the departure ends of the loops. I think this was part of the 1930’s upgrade on the line (also the Minehead line which is why I had the appendix out in the first place!). None of the other stations on the Barnstaple line had this instruction.

In essence for those without access to the 1950 Rule Book, 39(a) is about not lowering the stop signal in rear of one at danger worked from the same box until the train has been brought quite of nearly at a stand.

 

Thanks Paul - that makes considerable sense about Rule 39(a) as you observed.   The Lightmoor book on the Taunton - Barnstaple line is an excellent publication and a quality follow up to Volume 1 (although there is a minor error on one of the signalbox diagrams - presumably incorrectly copied from the SRS original).

 

And as you say a number of crossing loops were very thoughtfully altered/provided on the Barnstaple and Minehead branches in the 1930s - showing taht someone in the GWR was well aware of the impact of the Block regulations on train crossing movements on single lines.

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E-FPLs were very common in Ireland, and in some cases they had fouling bars, heres an interesting one of a station I am currently modelling , with the bars on the outside ( FPL covers were removed from points in the 60s in Ireland )

 

( all gone now since 2011

 

claremorris-p.jpg

 

and a closer look at an E-FPL, with its array of gubbins , ( WellingtonBridge , Wexford , still in existence today, but line out of use )

 

post-23919-0-34790100-1516907351_thumb.jpg

 

Edit : I don't think the photo above is an economical FPL , as I see two operating rods

Edited by Junctionmad
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On 25/01/2018 at 15:45, The Stationmaster said:
On 25/01/2018 at 11:42, PD&SWJR said:

I had my copy of the 1960 Exeter District Sectional appendix out the other day, and an entry for Venn Cross caught my eye: “The provisions of Rule 39(a) do not apply to the operation of the Down Home signal so far as Down Freight and Down Passenger trains, booked to stop at Venn Cross, are concerned.” I guess they really did not want to stop trains in that tunnel / on that gradient. Looking at the recently published Lightmoor book on the Taunton - Barnstaple, the signal box diagrams show that all the loops on this line had traps at the departure ends of the loops. I think this was part of the 1930’s upgrade on the line (also the Minehead line which is why I had the appendix out in the first place!). None of the other stations on the Barnstaple line had this instruction.

In essence for those without access to the 1950 Rule Book, 39(a) is about not lowering the stop signal in rear of one at danger worked from the same box until the train has been brought quite of nearly at a stand.

 

Thanks Paul - that makes considerable sense about Rule 39(a) as you observed.   The Lightmoor book on the Taunton - Barnstaple line is an excellent publication and a quality follow up to Volume 1 (although there is a minor error on one of the signalbox diagrams - presumably incorrectly copied from the SRS original).

 

And as you say a number of crossing loops were very thoughtfully altered/provided on the Barnstaple and Minehead branches in the 1930s - showing taht someone in the GWR was well aware of the impact of the Block regulations on train crossing movements on single lines.

Now that's very useful info; especially as I'm lined up to make a model of a Minehead branch station...  Many thanks for posting. 

What I was looking for when I found this was an answer to the following question (might this be one for you, Mick Nick?)  Below is a photo of Clare's east end blockwork, including an FPL and locking bar - but with three rows of point-rodding leading to it.  So one's the blade movement, the nearest must be the FPL and bar, (with is that an extension of that to a length of rodding to the side to allow that ground signal to be pulled?  And and an unseen Home too, presumably...), but what is the further one for?  And no, it's not the catch-point for the siding on the left, that's the 4th one along...   
Anyway, here's the photo; can anyone offer any clues?  

Clare[EEnd]FromOvrBr-d-s.jpg

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11 minutes ago, Mrs Durby said:

Now that's very useful info; especially as I'm lined up to make a model of a Minehead branch station...  Many thanks for posting. 

What I was looking for when I found this was an answer to the following question (might this be one for you, Mick Nick?)  Below is a photo of Clare's east end blockwork, including an FPL and locking bar - but with three rows of point-rodding leading to it.  So one's the blade movement, the nearest must be the FPL and bar, (with is that an extension of that to a length of rodding to the side to allow that ground signal to be pulled?  And and an unseen Home too, presumably...), but what is the further one for?  And no, it's not the catch-point for the siding on the left, that's the 4th one along...   
Anyway, here's the photo; can anyone offer any clues?  

Clare[EEnd]FromOvrBr-d-s.jpg

Is it the detection on the home signal? 

If you need any minehead branch info, let me know.  

Ian

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24 minutes ago, ikcdab said:

Is it the detection on the home signal? 

If you need any minehead branch info, let me know.  

Ian

Hello Ian,

 

Detection

I don't think so.  The signal wires are running down the LHS, not the right, and I think  the detection is done on that side. If so, that explains what I think is rodding from the middle of the FPL cover plate, heading to the left but difficult to see owing to the tree shadow.  My guess - and as this was c.1947 and now long gone - is that it might be to help move the long blades of the long point, which is probably at least a C10...  Fwiw, I am fairly convinced there were only 2 sets of rodding running down that RHS as far as that point and if so, that suggests something's duplicated somewhere.  But why?

 

What is interesting is that possibly by the late 50s, or certainly by the early 60s anyway, it has disappeared - that suggests to me that it's a GE design and BR altered it to more 'standard practise' when it needed renewal...  But that's only a guess and I'm not at all familiar with GE point-rodding practise, which is why I'm asking !   Why would one point need three sets of rodding?  

 

Minehead Branch

Oh, and thanks for asking about the Minehead branch.   Could you confirm that 'Rule 39a' was suspended by 1947?  (I note it was in the 1950 rule book, but that the suggestion is that catch points were added to enable that rule change in the 1930 revisions to the line.)  

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Best I can make out, the additional roding is for the "Back Drive", looking it the photo' which is low definition and wont enlarge, this rod is connected to an additional stretcher. I have somewhere a close up picture, but typically, I cant find it.

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2 minutes ago, micknich2003 said:

Best I can make out, the additional rodding is for the "Back Drive",

Hi Mick, (Andy here), can I take it by 'Back Drive' you mean ensuring that the long blades' centres move clear of the flangeways?  

 

Here's what I've made of it so far... 

DSCF0211.JPG

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46 minutes ago, Mrs Durby said:

Minehead Branch

Oh, and thanks for asking about the Minehead branch.   Could you confirm that 'Rule 39a' was suspended by 1947?  (I note it was in the 1950 rule book, but that the suggestion is that catch points were added to enable that rule change in the 1930 revisions to the line.)  

 

I think that depends on the individual signalbox and all my sectional appendices are now held away so I can't check at the moment. 

At bishops lydeard, crowcombe, Leigh bridge, williton and kentsford, both ends of the loops were trapped during the late 1930s.

Washford was not a passing loop.

Blue Anchor did not have any outgoing traps.

Dunster was the start of the double line to minehead. 

So I guess the answer to your question is yes apart from Washford and Blue Anchor.

Ian

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Thanks Mick.  Not sure I really need to model anything too accurate in 2mm scale, but as the blades need to work, while the rodding doesn't, I can't make the 'bar' long enough to risk a short between the rails!    

Thanks again.  :read: 

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Some of my photos that may be of interest. First, a simple facing point lock on the Mid Hants Railway:

 

Mid Hants Railway Track Details

 

and one with signal wire locks next to the point:

 

Mid Hants Railway Track Details

 

And a facing point lock with fouling bar:

 

Mid Hants Railway Track Details Mid Hants Railway Track Details

 

Mid Hants Railway Track Details

 

Mid Hants Railway Track Details

 

 

When the locking bolt is being inserted or released, the fouling bar would rise and fall in an arc movement. If a train were standing there, the fouling bar could not be raised, so it is impossible to either insert or release the lock.

 

 

Here is the model version I made for my layout, 'Freshwater'.

 

IMG_20200309_214406

 

 

 

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16 hours ago, Mrs Durby said:

Hello Ian,

 

 

Minehead Branch

Oh, and thanks for asking about the Minehead branch.   Could you confirm that 'Rule 39a' was suspended by 1947?  (I note it was in the 1950 rule book, but that the suggestion is that catch points were added to enable that rule change in the 1930 revisions to the line.)  

You seem to be confusing two things here.  Venn Cross was a special situation due to the gradient etc as discussed previously - hence that particular Home Signal was exempted from Rule 39(a).

 

What the provision of trap points at the exit end of loops allows (exemplified by the 1930s alterations on the Minehead branch) was  an exemption from part of the 'Working of Fixed Signals' Instructions in the Electric Train Token (ETT) Block Regulations which in effect  required trains approaching a crossing loop from both directions at the same time to be brought to a stand at the Home Signal.    This is, I find having just looked, also explained on Page 91 of Ian Coleby's book about the Minehead branch.   After the 1930s alterations Blue Anchor was the only place on the branch where the approach to a double to single connection did not have a trap point although there was a catch ppoint in the Up loop because of teh rid sing gradient towards washford

 

Rule 39(a) would still apply to any stop signal unless there were any particular local conditions (as at Venn Cross) to require a signal, including a Home Signal, to be exempted from it. 

 

Rule 39(a) exemptions are normally only shown in Signal Box Footnotes (GWR )/Special Instructions (BR).  They are not normally included in the Sectional Appendix. 

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