GW BLT - Signal Box Diagram

[Coombe Barton]

Are you going to have an Interlocking Frame?

That's the original aim. However this may be tempered by room, time and practicality. I'm taking advice but need to do a load of drawing so that I can get the engineering right.

[Donw]

The general principle in laying out the box was to number the levers from the left. Connections to the levers would be made to minimise crossing of rodding and signal wires. Frames usually came in standard sizes so spare levers were common and were usefull for changes and additions. Your layout looks pretty good to me.

 

The advance starter allows the starter to be pulled off without having gone through the block signalling to allow the loco to proceed to the shunt signal. If you move the shunt signal back to the starter you then have difficulty signalling from the loop. Hence I feel that the advance starter would be prefered. However I am sure you could find somewhere signalled differently.

 

Donw

[The Stationmaster]

The general principle in laying out the box was to number the levers from the left. Connections to the levers would be made to minimise crossing of rodding and signal wires. Frames usually came in standard sizes so spare levers were common and were usefull for changes and additions. Your layout looks pretty good to me.

 

The advance starter allows the starter to be pulled off without having gone through the block signalling to allow the loco to proceed to the shunt signal. If you move the shunt signal back to the starter you then have difficulty signalling from the loop. Hence I feel that the advance starter would be prefered. However I am sure you could find somewhere signalled differently.

 

Donw

 

I'm just trying to work out why a Shunt Ahead signal would not be below the most advanaced starting signal - i.e the Section Signal - and I can't as it's very purpose was to signal a shunting movement into the section in advance for shunting purposes. (apart from the totally incorrect preserved railway use of one at Buckfastleigh of course - but it is a lovely looking signal and well worth preserving where it can be seen).

[Coombe Barton]

The advance starter allows the starter to be pulled off without having gone through the block signalling to allow the loco to proceed to the shunt signal. If you move the shunt signal back to the starter you then have difficulty signalling from the loop. Hence I feel that the advance starter would be prefered. However I am sure you could find somewhere signalled differently.

The shunt is on the adv starter. Prototype for this in GW BLT that I have diagrams for - Kingsbridge, Brixham, St Ives. For Brixham there is an intermediate start as well, and trains could depart via the loop as well as the main.

[beast66606]

The advance starter allows the starter to be pulled off without having gone through the block signalling to allow the loco to proceed to the shunt signal.

 

Isn't blocking back required unless there is an outer home ?? - the only single line I've ever seen was tokenless block so I don't know much about token working

[Poor Old Bruce]

Just had a quick look through this thread and two thing spring to mind:

 

1: Has anybody mentioned a 'Limit of Shunt' board?

2: Should Dolly 11 be yellow?

 

Richard

[Coombe Barton]

Just had a quick look through this thread and two thing spring to mind:

 

1: Has anybody mentioned a 'Limit of Shunt' board?

2: Should Dolly 11 be yellow?

 

Richard

1. Not yet

2. Based on what logic? This implies that the signal may be passed when in the on position, but 11 is protecting a point onto the main line.

[beast66606]

Just had a quick look through this thread and two thing spring to mind:

 

1: Has anybody mentioned a 'Limit of Shunt' board?

2: Should Dolly 11 be yellow?

 

Richard

 

 

1. No - not required

2. No

[The Stationmaster]

Isn't blocking back required unless there is an outer home ?? - the only single line I've ever seen was tokenless block so I don't know much about token working

 

 

A 3-3 Block Back is required for a shunt outside the (outermost) Home Signal unless the shunt is being made into the section following the departure of a train going away from that token station (in which case the 3-3 would be sent - if the shunt is still outside the Home Signal of course - after 'Train Out of Section' has been received for the train which was going away).

 

The last time I did the latter (showing my age now) was to shunt a D10XX and train (c.10/11 on) back out into an occupied single line section after giving a departing passenger train a chance to get well on its way.

 

As far as a 'Limit Of Shunt' is concerned - you can't have one where it would be facing to running movements (although one UK tourist railway is installing one in exactly such a situation over the present winter ).

[Poor Old Bruce]

but 11 is protecting a point onto the main line.

 

I was not referring to 11 on the original diagram but that on the revised version where there is a siding to a Warehouse/Mill.

 

In the early 1960s there was a 'limit of Shunt' board on the main line outside Llanfair Ceareinion.

 

Richard

[The Stationmaster]

I was not referring to 11 on the original diagram but that on the revised version where there is a siding to a Warehouse/Mill.

 

In the early 1960s there was a 'limit of Shunt' board on the main line outside Llanfair Ceareinion.

 

Richard

 

As far as disc is 11 is concerned the WR did not start using 'yellow arm' discs until January 1950 - and then only in new work, they never seem to have carried out a 'campaign' conversion although quite a number of signals suitable for yellow arms were converted by the mid-late 1960s (and others weren't).

 

Judging by your remarks regarding Llanfair Caereinion there are now (at least?) two UK tourist railways making 'peculiar' use of a 'Limit Of Shunt' board. But - as the Signal Engineer on one of them said to me not long back - there is nothing to prevent them adopting an unusual arrangement in their signalling installations, provided they issue suitable instructions to cover it.

 

And - excuse me for pinching the thread - there lies a warning for the unwary - do not be misled by the signalling you see on a preserved railway because they have done it that way for a reason - on a line which is usually far busier and has more movements than it ever did as a 'real' railway. There are some smashing preserved signals to be seen but some, such as the one I mentioned above on the Dart Valley, are not the correct form for the job they are doing or might not have been typical at such a location in its past.

[Coombe Barton]

Things have come to a dead halt here - something called work. Early in and late home.

 

I'm in the process of making a full sized plan and some building mockups so that I can see how much control mechanisms I can fit in. And, of course, puzzling how to make mechanical control cross baseboard joins. The layout will be demountable and I'm designing storage/transpotrtation units to take it, so the space must be enough to take the finished article. Or the finished article must conform to the space requirements.

 

But its all on hold at the moment.

[Donw]

I have seen articles where mechanical methods were operated across baseboard joints;

 

1. Using a push rod against another rod sprung loaded to return.

2. Using a link connected up after setting up the baseboard

3. Having a lever frame which itself straddled a basboard joint and was effectively in two halves. Difficult to interlock!

Donw

[Poor Old Bruce]

As far as disc is 11 is concerned the WR did not start using 'yellow arm' discs until January 1950 -

 

there are now (at least?) two UK tourist railways making 'peculiar' use of a 'Limit Of Shunt' board.

 

And - excuse me for pinching the thread - there lies a warning for the unwary - do not be misled by the signalling you see on a preserved railway

 

Thanks for the explanations Mike.

 

Richard

[Coombe Barton]

I have seen articles where mechanical methods were operated across baseboard joints;

 

1. Using a push rod against another rod sprung loaded to return.

2. Using a link connected up after setting up the baseboard

3. Having a lever frame which itself straddled a basboard joint and was effectively in two halves. Difficult to interlock!

Donw

I'm favouring 1. Almost automatic, I'd like to think.

 

Of the two main baseboard joints one would have two such connectors, the other would have three. The swear box is going to profit, methinks.

[Pannier Tank]

I'm building the lever frame from brass with hand tools. I can't yet afford a lathe and mill. I saw the impressive frames made by Vince Worthington at ExpoEm North last yar (MRJ 193) so I'm adapring his designs using non-turned, non milled but filed working. This is probablly going to be a swearbox filling exercise.

 

You may find the Scalefour Society's Lever Frame componenets of some use; in particular the Lever Handles.

 

http://www.scalefour...ublications.htm

[Coombe Barton]

You may find the Scalefour Society's Lever Frame componenets of some use; in particular the Lever Handles.

Thanks, David - now on my radar.