Catch points

[beast66606]

A lot of time on models you can design so the pointwork provides natural protection e.g rather than the sidings connecting straight onto a running line a crossover with a short headshunt provides effective protection and will be obvious to the novice operator. The crossover needs to be worked by one lever though. This also questions whether one should go to the trouble of facing point locks?

Don

 

My embolding.

 

Not strictly true, the (model) locking needs to prevent the signals clearing until both points are over, this could be done with one or two levers , depending on distance.

 

Working FPLs would serve no real purpose other than for looks.

[ozzyo]

I seem to remember a photo of a station? where the trap point was a bit different in that had two traps one going to the left and one going to the right. I've not explained that to well. But I think there was a running line on both side so the idea was to drop the train straight down in to the dirt and not go to ether side.

 

OzzyO.

[Free At Last]

I seem to remember a photo of a station? where the trap point was a bit different in that had two traps one going to the left and one going to the right. I've not explained that to well. But I think there was a running line on both side so the idea was to drop the train straight down in to the dirt and not go to ether side.

 

OzzyO.

You reminded of this which I was looking at recently. Is this one or is it just the remains of uplifted track?

[TheSignalEngineer]

I seem to remember a photo of a station? where the trap point was a bit different in that had two traps one going to the left and one going to the right. I've not explained that to well. But I think there was a running line on both side so the idea was to drop the train straight down in to the dirt and not go to ether side.

 

OzzyO.

 

Wide-to-gauge traps. There used to be a nice set worked by a GRS 5A machine at the north end of Snow Hill where the siding was between two running lines. The idea was that if anything dropped off it would stay upright and in line without fouling the lines on either side.

I think in the case of Snow Hill, before the colour light resignalling a derailment to the right would have also demolished Birmingham North Signal Box (the one on columns)

[beast66606]

Wide-to-gauge traps.

 

2 by me, one at Bootle Branch Junction (Edge Hill) and one at Liverpool Lime Street (engine neck), clamp locks at EH and motors (iirc) at Lime Street

[ozzyo]

You reminded of this which I was looking at recently. Is this one or is it just the remains of uplifted track?

 

 

Thank you that was what I was trying to describe.

And thank to the signal engineer for his explanation of the type of trap.

 

OzzyO.

[Oldddudders]

Thank you that was what I was trying to describe.

And thank to the signal engineer for his explanation of the type of trap.

I have a feeling that there is a wide-to-gauge trap at the exit of the bounceback siding for Bakerloo trains at Harrow & Wealdstone. Since the siding is only just long enough for the train, it means that if a driver finds himself in the trap, he's probably doing about 5 mph, having just passed the signal at danger. When, a few years back, there was press and public angst about SPADs, this was solemnly listed as a high-risk location, based upon the number of SPADs there, thus ignoring the fact that the trapping and low speed ensured there could never be any effect on a passing passenger train.

[Derby Road]

That is actually a 'trap' Point Ian. Catch points are on rising gradients to 'catch' runaway wagons running into a following train if the train divides. They date back to the days of unfitted freight trains, nowadys with fully fitted freights, the brake pipe should part and apply the auotmatic brakes so catch points are becoming a thing of the past (if there are any left at all), certainly they were elininated from the WCML in the 1970s when the Weaver Junctio to Glasgow electrification scheme was installed. Unfitted freights were re-routed after that.

 

I have definitions of 'trap' and 'catch' points in a hundred-year-old book at home. Will transcribe and post when I can.

 

If I've got the definitions right, there is still seems to be at least one catch point on the Lickey Incline. It's just north of the bridge taking the B4184 over the line and can be seen if you zoom in using streetview.

 

Cheers,

Gareth

[beast66606]

The Edge Hill wide to gauge photographed by Big Jim is in this thread

[lonesome_whistle]

On a practical basis, I was delighted to see the abolition of catchpoints. Having severely strained myself when attempting to close one so we could run wrong-road with a failed train - and we never did manage to close them - I regarded tham as a necessary evil that the fully-fitted railway did well to avoid. Hopefully modelled ones work a trifle more easily!

 

Bit of a nuisance when setting up single line working too. All sorts of potential pitfalls when clipping and padlocking the things as I'm sure one or two folk can attest to.

 

To be truly authentic, most steam-era catch points were unworked and were sprung in the open position and would just be trailed through by passing trains - that could be tricky to model - particularly if some of your rolling stock is a bit lightweight. On a related subject some of the most gut-churning moments I have had have been when holding a set of spring points closed while a train of 102t stone wagons is being set back through them at 15 or so mph.. you just close your eyes and hope for the best!

[Oldddudders]

Bit of a nuisance when setting up single line working too. All sorts of potential pitfalls when clipping and padlocking the things as I'm sure one or two folk can attest to.

 

To be truly authentic, most steam-era catch points were unworked and were sprung in the open position and would just be trailed through by passing trains - that could be tricky to model - particularly if some of your rolling stock is a bit lightweight. On a related subject some of the most gut-churning moments I have had have been when holding a set of spring points closed while a train of 102t stone wagons is being set back through them at 15 or so mph.. you just close your eyes and hope for the best!

Only half a mile from the recalcitrant catch-point I was berating earlier, there was, inside the yard at Grove Park shed, a "spring handle" where you pulled the points over, and then stood on a treadle to hold them in place while the train went past into the shed. Losing your balance on the treadle spelt disaster, as the shunter found out one evening in 1976, resulting in a 10-EPB with the front coach on the floor, and the rear of the train blocking the down slow. Doh!

[The Stationmaster]

On a practical basis, I was delighted to see the abolition of catchpoints. Having severely strained myself when attempting to close one so we could run wrong-road with a failed train - and we never did manage to close them - I regarded tham as a necessary evil that the fully-fitted railway did well to avoid.

 

er, yes (or putting it another way - if you want to get ahead, get off the road)

[Donw]

My embolding.

 

Not strictly true, the (model) locking needs to prevent the signals clearing until both points are over, this could be done with one or two levers , depending on distance.

 

Working FPLs would serve no real purpose other than for looks.

 

I stand corrected yes if the points were interlocked that would provide the protection.

 

I know FPLs would serve know real purpose. Although switching a point under expensive 0 coaches might make you wish you had one. However it could add to the pleasure of operating and make you think before throwing switches. Operating realism can be good fun too.

Don

[caradoc]

Some large signalboxes feature(d) separate train describers for fitted and unfitted trains, so that on a rising gradient the situation of "always have a catch point between an unfitted train and the train in rear" could be easily imposed. Doncaster had them when it was commissioned, according to magazine articles I have; and I've been told Motherwell box did too. Presumably, if this is all the case, Motherwell box must predate the electrification scheme?

 

Motherwell Signalling Centre was built as an integral part of the electrification scheme. While catch points were removed on the WCML south of Carlisle, they were retained northwards, due to the number of unfitted or partially fitted freights using the route, to reach industrial areas such as Lanarkshire for which there was no suitable alternative route. OS Nock's book 'Electric Euston to Glasgow' (Ian Allan 1974) has an interesting description of the method of signalling used for the catch points on Beattock Bank. There are no catch points on the WCML now, however. The fact that they had to be provided at all, in the 1970s, speaks volumes about the backwardness of BR freight operations at the time.

 

This book, and OS Nock's earlier volume about the Euston/Birmingham/Liverpool/Manchester electrification, 'Britain's New Railway' (Ian Allan 1966), contain fascinating detail about the WCML in the 1960s and 1970s, in particular before and after track plans, and are well worth getting if they can be found in a second-hand bookshop.

[craigwelsh]

I don't think I've ever seen a true catch point modelled. I suppose not many people choose to model the bottom of a steep gradient. Though it has operating potential for steam era modelling, attaching bankers, halting trains that have come down the bank to unpin brakes, and so on.

 

I seem to recall they were sometimes put in part way down banks as well. To protect the block section in the rear?

They are fitted on the P4 model of Sheep Pasture incline though that is a rather extreme example of a bank!

[beast66606]

Operating realism can be good fun too.

 

You haven't seen Widnes then

[avonside1563]

Stafford Railway Circle's 'New Haden Colliery' has a trap point at the boundary fence protecting the Cheadle branch from the colliery sidings, as per the original.

[Edwin_m]

A catch point might be put in part way up a bank to prevent a train rolling back into any following train approaching a signal further down the bank. There was an accident at Inverkeithing-North Queensferry where a train slid back and derailed on a catch point leaving a coach teetering on the top of a high embankment, and the report states that the catch was so positioned to be 440yd in advance of a stop signal.

 

There were (unsurprisingly) other many accidents relating to catch points. One that springs to mind (sorry) was near Oxenholme where during single line working the catch points were correctly locked in place for running in both directions. The person in charge passed through on a train and shouted to one of the staff on the engineering train to "get that off" meaning to move the train out of the section as the possession would soon end. The person concerned went and "got off" the clips and scotches, so that the final train to go wrong direction on the single line ended up down the bank...

[Poor Old Bruce]

True Catch Points, i.e. those provided for run-back protection on a running line were only provided on rising gradients steeper than 1 in 260.

 

To me, maybe others, the catch point is there to catch, and divert into the cess, the runaway going in the wrong direction, and has a hand-operated lever to reverse it, while the trap is a part of the signalled safety system, typically preventing an unauthorised movement from a line or siding which would foul another running line.

 

official terminology for at least 50 years has been for a catch point to be for run-backs on gradients and a trap point to derail unauthorised moves out of sidings etc.

Seems that most people have a general grasp of what's what anyway.

[Happy Hippo]

Many years ago I remember the climb out from Cardiff Queen Street to Caerphilly had quite a few catch points between QS and Heath Junction in case an unfitted freight came apart. I don't know if this arrangement continued up through Llanishien and the Cefn Onn Tunnel (I expect it did). Last time I rode over the line they had all gone. I expect they went soon after the abolishment of unfitted freights.

 

However, I do not remember them on the Merthyr line from QS to Radyr, perhaps the incline is not as great.

 

If that was the case, is there a specific gradient at which catch points would be considered necessary?

 

Regards

 

Richard

[Poor Old Bruce]

is there a specific gradient at which catch points would be considered necessary?

 

True Catch Points, i.e. those provided for run-back protection on a running line were only provided on rising gradients steeper than 1 in 260.

[tomparryharry]

Many years ago I remember the climb out from Cardiff Queen Street to Caerphilly had quite a few catch points between QS and Heath Junction in case an unfitted freight came apart. I don't know if this arrangement continued up through Llanishien and the Cefn Onn Tunnel (I expect it did). Last time I rode over the line they had all gone. I expect they went soon after the abolishment of unfitted freights.

 

However, I do not remember them on the Merthyr line from QS to Radyr, perhaps the incline is not as great.

 

If that was the case, is there a specific gradient at which catch points would be considered necessary?

 

Regards

 

Richard

 

 

You're on the collar all the way up to Caerphilly..... There used to be a sand drag at Walnut Tree Jcn to protect the junction from the 'big hill'.

 

Regards,

Ian

[The Stationmaster]

You're on the collar all the way up to Caerphilly..... There used to be a sand drag at Walnut Tree Jcn to protect the junction from the 'big hill'.

 

Regards,

Ian

 

And the interesting thing about the one at Walnut tree Jcn was that it was a spring slotted catch point (plus two other ordinary catch points further up the hill -but then I was 1 in 48. Another interesting oddity on some of the Valleys freight only branches was the presence of catch points on single lines - all of them (AFAIK) spring slotted points connected to a nearby signal box.

[Guest jim s-w]

Hi All

 

I am doing my bit to bring the average up! My station has 8 trap points (dont add up the cost of tortoises - Its depressing!)

 

Heres a couple of them although these 2 are not connected up yet.

 

 

Cheers

 

Jim

[Donw]

A friend has two sprung (well weighted actually) crossover on a garden layout which allow trains accessing the main from a single point junction to cross over to the right road with out needing motors to activate the points. They work well until someone misses the junction and backs up a train halfway past the crossover ending up with half the train on the up and half on the down. I could see catch points having the same sort of possibilities on a model layout. You could back up or simply have the controller set wrongly and shove half the train off the baseboard edge.

Don