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Strange " mini dollies " at Claremorris pre 80s

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Strange " mini dollies " at Claremorris pre 80s

Unread postby madscientist » Mon Feb 20, 2017 6:56 pm

IN my research into Claremorris signalling before the closure of the Burma road , I discovered from this photo ( you can use the zoom feature )
http://catalogue.nli.ie/Record/vtls000306959
(c) Odea Collection NLI

Which shows the junction signals ( there were two identical signals close to each other , on the approach roads from Balla and Kiltimagh ( westport , sligo ) . Note how small the dollies are , in fact the signal post construction seems identical to a similar " calling on " signal further into the station
http://signalbox.org/overseas/ireland/claremorris-s2.jpg
(c) Janet Cottrell

Later when the Burma road was closed the remaining junction signal ( the main signal refers to platform 2 and the minor signal to platform 1) was replaced with a more conventional dolly signal

One would almost think this was a subsidiary signal , but clearly ( from other photos ) the lower one refers to the loop road .

strange that the calling on and junction signals would be very similar ( albeit the Junction minor arms would be red)


anyone any comments
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby Wilkinstown » Tue Feb 21, 2017 1:06 am

The practice adopted at former Midland stations (MGWR) following singling of the mainline west of Clonsilla was to arrange signals in such a way that the main home could only be cleared if the main starting signal was off. The main starting signal could not be cleared unless token release had been obtained for the forward section. If the main starting signal could not be cleared, a subsidiary signal ("call on"), co-sited with the home signal could be cleared and this read to either the main starter or loop starter depending on the lie of the points.

At Claremorris, if I recall correctly the Sligo road ran directly to the up platform and the Westport road to the down platform with crossovers allowing trains from either line access either of these platforms. The "call on" signals in the illustration, as far as I understand it, read to the opposite running line - up platform running line in the case of Westport trains and down platform running line in the case of Sligo trains. I have some drawings somewhere which may shed more information.
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby madscientist » Tue Feb 21, 2017 11:54 am

What a bizarre arrangement , does that mean that a version of Rule 39 was not used , i.e. The main signal could not be used to check the train .

Even more so , given the resignalling of the branch by the GSR in the 40s and 50s , one would have imagined the midland practice would have been discontinued in favour of rule 39 working and conventional dolly signals. ( as was prevalent at n the southern approaches to Claremorris )

From my reading of the signalling diagram and the dolly priorities of the signals of Athlone and tuam approaches , platform 2 was the main road signalled both up and down , with platform 1 being a loop

Both homes therefore , when arriving either via the Burma road or from Westport , would therefore refer to platform 2 , despite the track arrangement .

So , it must mean that the main approach home signals , from Westport and Sligo , refer to either road, and hence the calling on arm below equally refers to each road. Unusual that the driver couldn't ascertain which platform was being signalled

What's also strange is the use of the term " calling on " , because my understanding was that calling on was used where the section ahead was obstructed , not simply that the starter wasn't released ( which was usually dealt with via rule 39 )

Thank you , I'm modelling clatemorris in the mid 70s , with the assumption of working Burma road and ballinrobe branch and therefore trying to modify the 1960s signalling to reflect CIE practice

I know that after the manulla accident , in the mid 60s, the use of calling on arms was severely restricted. And in fact by the early 80s the peculiar homes , where replaced by a more conventional junction dolly ( but of course the Burma road signalling was gone by then )

Any info much appreciated

Dave
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby madscientist » Tue Feb 21, 2017 12:42 pm

whats even further confusing is that Odea's picture of the signal diagram in the cabin , from 1960 , shows a different , more conventional junction dolly arrangement , that doesnt reflect whats outside the window based on the 1963 picture , and the midland was long gone by 1960 !

I wonder was it the case that the cabin diagram reflected the retaking of the signal as a junction home, whereas the physical signal was the same as the older midland calling-on usage

Checking photographs, I can see the calling on signal type remained in place even after the signalling of the Burma road was removed and by 1988 the signal was changed got a more conventional junction dolly.

I think it must have been the situation where the main signal and its sub-sid below read too both roads
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby Wilkinstown » Tue Feb 21, 2017 9:39 pm

I may have created a little unintentional confusion. The arrangements I referenced on former MGWR lines were introduced by the GSR in the 1920s and I was suggesting that the practice adopted at that time may have influenced the signalling at the west end of Claremorris which I believe was renewed in the 1950s.

I am not sure as to the meaning of the home signals shown in O'Dea's photograph of the west end at Claremorris. I suspect that the main arms read along the straight road and the subsidiary signals read over the crossover roads. So a Sligo train with the main aspect would run to the main up platform with the subsidiary signal reading to the down platform line. A Westport train would run under the authority of the main arm to the down platform and would run to the up platform under the authority of the subsidiary signal. I have some more information somewhere but will need to do some digging !
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby madscientist » Wed Feb 22, 2017 2:02 pm

If you look at the odea photograph taken in 1960 of the cabin diagram, you see what would to most people be read as a junction signal . On the Westport road the priority reading a dolly left to right mean that the major signal referred to the " left road , i.e. Platform 1. The nominal " up platform " the dolly referring to the right , platform 2 ( the down platform )

Confusingly the junction dolly on the diagram from the Burma road ( Sligo ) was the same aspect , with the dolly to the right as well. Indicating the main signal was again pointing to the "up " platform
The dolly again pointing to platform 2

The actual signal I suspect was however a remnant of the MGWR practice of calling on with both posts ( Sligo & Westport ) showing a main signal with a mini dolly below , to confuse things this mini dolly is to the left of the signal post even when the cabin diagram shows it clearly to the right.

Hence I believe the posts are remnants of the MGWR practice that survived physically till the late eighties , even though CIE had abandoned the calling on practice after the manulla junction accident

It then further confusing that CIE replaced the original signal with a new regular dolly with opposite priority by 1988 , designating platform 2 , as the main line ( which represented the track work ) while the dolly was now to the left indicating platform 1 ( and that was the habitual route. )

The late 1980 to closure cabin diagrams then reflected that reality , interesting the order of the levers remained as previous 1960 diagram, even if the dolly priority was reversed

A curious one
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby Wilkinstown » Sat Feb 25, 2017 1:04 pm

"Madscientist" You refer to an accident at Manulla Junction in the mid 1960s - do you have any more details ?
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby madscientist » Sat Feb 25, 2017 11:49 pm

Wilkinstown wrote:"Madscientist" You refer to an accident at Manulla Junction in the mid 1960s - do you have any more details ?


The incident was relayed to me by another , seemingly an aec rail car crashed into a C class shunting at manulla as a result of a calling on arm not being replaced.

But strangely I can find no official accident report or even independent mention , so I can be sure of any original facts
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby Wilkinstown » Sun Feb 26, 2017 11:27 am

If you look at the signalling diagram for Manulla Junction at http://catalogue.nli.ie/Record/vtls000306641, you can see that the subsidiary signal (No 26) sited to the left of the up home signal (confirmed by the photograph at http://catalogue.nli.ie/Record/vtls000306950) actually reads to the loop despite this being geograpically to the right.

I am now inclined to think that the arrangement of the up home signals at Claremorris (as in the early 1960s) is similar to that which applied at Manulla around the same time. The subsidiary signal simply read to the lower speed route. At Claremorris, I now suspect that the subsidiary home signals at the west end of Claremorris read to the slower route only. This is different to the arrangement which applied at crossing points on the former double line segments of the midland main line where, post singling, the subsidiary signal could read to either the main or loop lines. As I mentioned before the main home signals at these stations could not be lowered unless the main starter had already been lowered. The main starter in turn could not be lowered unless the section token had been released.
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby madscientist » Sun Feb 26, 2017 1:17 pm

Wilkinstown wrote:If you look at the signalling diagram for Manulla Junction at http://catalogue.nli.ie/Record/vtls000306641, you can see that the subsidiary signal (No 26) sited to the left of the up home signal (confirmed by the photograph at http://catalogue.nli.ie/Record/vtls000306950) actually reads to the loop despite this being geograpically to the right.



I am now inclined to think that the arrangement of the up home signals at Claremorris (as in the early 1960s) is similar to that which applied at Manulla around the same time. The subsidiary signal simply read to the lower speed route. At Claremorris, I now suspect that the subsidiary home signals at the west end of Claremorris read to the slower route only. This is different to the arrangement which applied at crossing points on the former double line segments of the midland main line where, post singling, the subsidiary signal could read to either the main or loop lines. As I mentioned before the main home signals at these stations could not be lowered unless the main starter had already been lowered. The main starter in turn could not be lowered unless the section token had been released.


Firstly I fail to see how you can deduce , in the absence of any other information that #26 reads to the loop.

You are making a contradictory statement here. If the main signal read to the direst fastest route , irrespective of the physical orientation of the mini dolly , then your second comment about interlocking with the starter makes no sense. No semaphore system I'm aware of , would force a train to remain at the home , until the block ahead was cleared. It was the whole reason rule 39 existed. If you read the mini dolly signal as a simple junction signal , you must be able to apply " checking of trains " to the main signal. Otherwise a train using that line into the station , signalled by the main signal arm would be prevented from drawing into the station, until any train n the forward block section had cleared that block !!! ( that was not the case )

Furthermore , while many web and Thompson machines were so fitted, there is no evidence that the claremorris starters were interlocked with the staff machines. The staff machines had no key release ( electrical release was not used as the dept of P & T maintained the ETS machines and lines in Ireland unlike the U.K. ) and as a result , the ets machine were largely hand generator powered to the very end of their existence , which precluded any form of electrical interlock . The normal approach followed was to have the release of the staff , also allow a key to be released , which could then be used to release the starter , this was common but not ubiquitous.

I suggest that pre a change of purpose sometime in the 60s as a result of an accident , the sgnal main arm was read to both last lines as did the calling on arm. This would allow interlocking of the starter to the home , while still allowing trains to enter station limits , on either line , by aplication of the calling on arm. ( I believe the incident at manulla , if it actually occurred there ? , was more likely that the calling on arm was lowered but the route was incorrrctly set , running the appraching train, that the driver habitually would have entered into the free road , onto a road occupied and the driver , couldn't then stop in time

( note that previously I was told that this incident had cured at claremorris , in neither case can I find any report that mentions it )

Post sixties CIE , I believe , retasked the same signals to mean simple loop,signals and the signal acted as you described in your first paragraph. I.e. The dolly read to the " loop " , irrespective of the physical side it was on the post. This would have meant that the interlocking was modified to allow the main signal to be pulled off even with the starter " on" to allow the train signalled by that arm to enter the station under rule 39 ( or its Irish equivalent ) . CIE in the late 80 s then replaced that physical post with a conventional junction dolly signal that match its purpose.


Hence I would conclude that the original purpose of the signals as well nstalked by the midland and continued on into gsr and early CIE days was that such , signals , i.e. The main arm read to either line and were so interlocked with the starter , and that the calling on arm was then used to draw trains into the station on either line.

What I still find perplexing , is that the Odea photographs of claremorris , show the cabin diagram with the mini dolly to the right of the post , while the signal itself had the dolly isto the left In my experience cabin diagrams were always corrected to respresebt what was actually outside the windows. I cannot square this anomaly
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby Mike Hodgson » Sun Feb 26, 2017 2:56 pm

I'm confused, but maybe this is to be expected in Ireland. If I understand this correctly,
the miniature arm on a home signal might be a call-on reading to whichever road is set or
it might read only to the loop, and if so
that loop might be either to the left or the right of the main arm
the main arm might read only to the main or
it might lead to either road, whichever is set
the main arm might be locked by the starter

I don't like the idea of changing the meaning of existing signals, as drivers will have got used to whatever they had become accustomed to, and there must surely have been a risk that they would forget and apply an obsolete old interpretation inappropriately. I hope the crews understood what the signals meant, but talk of the odd accident suggests that I'm not the only one confused.
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby Wilkinstown » Sun Feb 26, 2017 11:20 pm

I don't understand the confusion.

At Claremorris and Manulla Junction, main home cleared, road set for straight route. Subsidiary cleared, route set for subsidiary road (i.e not the straight road). The only unusual feature is that the position of the subsidiary signal does not correspond geographically - not the way I would have done it but I don't see the big deal as the subsidiary signal tells the driver he is not taking the main route. Basic route knowledge provides the remaining relevant information.

The arrangement was different at the former double track MGWR stations which were re-signalled in the 1920s when the lines concerned were reduced to single track. In this case the subsidiary home signal could read to either main or loop depending on the lie of the points. Either way the driver will have been cautioned by the subsidiary signal and should therefore have his train well under control passing the home signals.

As for checking trains, the main home at danger is fairly effective, once the signalman is happy the train is under control he can then call the train forward. Don't see any issue. At Manulla and Claremorris, in the up direction, the signal cleared will be the main arm for the straight road and the subsidiary for the secondary route. At some other stations, as described in the preceding paragraph, there was an additional control which prevented the main home being cleared unless the main starter was also cleared. At such stations the subsidiary read to either main or loop depending on circumstances.

Mike, the arrangements are so simple even the Irish had no problem understanding it !
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby John Hinson » Mon Feb 27, 2017 8:51 am

It might be worth remembering that a subsidiary signal indicates the line is only clear as far as can be seen, so there is no real need to tell a driver which route he is taking. In fact, if all routes are equal distance and equal speed, it isn't necessary for a main arm either (think Skegness). And speed signalling isn't specific about left or right divergence, eiher.

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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby Mike Hodgson » Mon Feb 27, 2017 10:35 am

John Hinson wrote:It might be worth remembering that a subsidiary signal indicates the line is only clear as far as can be seen,


Not if it's seen by the driver as a Warning arm (Rule 45 in old money) leading the driver to infer he has a clear run into the vacant platform, which is what I took to be the cause of the accident that was mentioned. I understood the discussion to say practice had been changed such that what had previously been a warning signal was in effect redesignated more restrictively to a call-on.
A somewhat similar unjustified assumption seems to be part of the problem behind the recent Plymouth accident, although in that case it was very clearly a call-on situation complete with route indication
https://www.gov.uk/raib-reports/collisi ... th-station
It is obviously good practice for drivers to look at the lie of the points as they approach, but in practice they reach a speed appropriate to what they (mis)understand the required movement to be and it can be too late by the time they realise.
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Re: Strange " mini dollies " at Claremorris pre 80s

Unread postby madscientist » Mon Feb 27, 2017 10:48 am

Wilkinstown wrote:I don't understand the confusion.

!!!!, you cant have the midland approach to locking without a calling on arm

At Claremorris and Manulla Junction, main home cleared, road set for straight route. Subsidiary cleared, route set for subsidiary road (i.e not the straight road). The only unusual feature is that the position of the subsidiary signal does not correspond geographically - not the way I would have done it but I don't see the big deal as the subsidiary signal tells the driver he is not taking the main route. Basic route knowledge provides the remaining relevant information.


My understanding is that originally the main arm read to both lines and the signal below was a true calling-on arm. after a accident, CIE redesigned the calling on arms, as a " loop home " , and as was typical did not change the physical signals until many years later.

The arrangement was different at the former double track MGWR stations which were re-signalled in the 1920s when the lines concerned were reduced to single track. In this case the subsidiary home signal could read to either main or loop depending on the lie of the points. Either way the driver will have been cautioned by the subsidiary signal and should therefore have his train well under control passing the home signals.


I beleive this was also the way the home at manulla and claremorris was originally interpreated was that the main arm did read to both lines and the subsids were also read to both lines, The Northern track work at claremorris, did not suffer the upheaval that occurred at the southern end in the 40s and 50s , and there all the signals are conventional dollies

As for checking trains, the main home at danger is fairly effective, once the signalman is happy the train is under control he can then call the train forward. Don't see any issue. At Manulla and Claremorris, in the up direction, the signal cleared will be the main arm for the straight road and the subsidiary for the secondary route. At some other stations, as described in the preceding paragraph, there was an additional control which prevented the main home being cleared unless the main starter was also cleared. At such stations the subsidiary read to either main or loop depending on circumstances.


You are mixing up signals periods that are decades apart. The evidence is that the GSR and early CIE continued the midland practice of the main arm reading to both roads ( which in itself is not unusual ) , a subsidiary signal , by definition , would therefore also read to both roads and was used when either road was not cleared to the starter or ( in claremorris , actually to the next home signal ,as there was one subsequently on both running lines in the station area , one of which to the day it was removed was a " true " calling on arm )

You cannot have checking of trains with a home interlocked to a starter , because there is no way to release the home, again as I mentioned , there was actually further inner homes ahead anyway before the starter was reached

Mike, the arrangements are so simple even the Irish had no problem understanding it !

leaving aside the fact that the arrangements by the midland would have been subject to board of trade oversight and are in essence UK arrangements !!!! :D , the Irish railways then had to sort it out !!
Last edited by madscientist on Mon Feb 27, 2017 11:14 am, edited 1 time in total.
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