Detonator Placers

[mike knowles]

These came up in conversation at the club last night. Apparently they were(are) a mechanical means of putting detonators on the track - operated from the signal box. I have to admit I had never previously heard of them, has anyone got any further info/pictures?

[Boris]

Sorted!

 

They do exactly what it says on the tin, detonators are placed on a running line to stop a train in an emergency or to protect an obstruction or in some cases engineering work (not det placers usually though).

 

 

Exhibits A and B detonator placers with the signalbox lever normal and reverse respectively.

 

 

Non-lever det placers - the raised stirrup is with the dets deployed, in the lowered position is the normal position with the dets back in the housing.

 

I am not sure how common these stirrup devices were outside the LNER area, most I have seen are levers not the stirrups. IIRC det placer levers were painted white with black chevrons, and the convention was usually chevrons going up for the up line(s), chevrons going down for the down line(s) and alternating for a single line.

 

 

 

(And only 36 minutes after the original post - you know where to send the beer coupons)

[The Stationmaster]

Regrettably I don't have any pics immediately to hand and I'm not sure what I do have apart from, probably, some pics of signalbox levers which do work detonator placers and possibly one picture of an Eastern Region single shot placer.

 

Detonators (also known as 'railway fog signals') are small circular objects which come in several forms, the most common being the type fitted with lead clips which enable them to be attached to the rail head. When a wheel passes over the detonator it crushes it causing it to explode with quite a loud bang - the idea being to attract a Driver's attention to, in many cases, something else such as a fixed signal or handsignal or other lineside indication.

 

Detonators can also be placed onto the railhead by placing machines and over the years these have come in many forms with several different applications. The simplest is what is known as a 'single shot detonator placer' which puts one or two (very close together) dets on the rail when the operating lever is pulled - these were more or less standard equipment at GWR signalboxes (except on single lines) and other Railways/Regions used similar equipment. The lever which woirks them is painted white with black chevrons - the chevrons point upward on the lever for an Up line placer and downwards for the lever working a Down Line placer. Once the dets have been exploded they have to be replaced by someone going to the placer.

 

Single shot placers worked by individual levers were also used at Distant Signals to enable them to to be easily worked by the Fogsignalman and to avoid him having to put a det down or pick it up according to the indication given by the Distant Signal. However the use of a single shot machine meant the Fogsignalman still had to replace any det which had been exploded and this could be hazardous, especially in multi-track areas. To get round this there were also 'multi-shot detonator placers' which had a magazine preloaded with a number of dets. As one was exploded operating the lever at the linside caused its remains to be removed and the next det from the magazine to be put in place.

 

In addition to individually worked placers det placers could also be worked in conjunction with other items - usually signals but sometimes points and such arrangements were usually found at places where there was a risk of a signal being passed at danger with a consequential collision. In later years, particularly on the North Eastern Region power operated placers were used in this way noramlly (AFAIK) using a standard Westinghouse signal motor to work them.

 

Finally (phew!) the GWR used a device known as a 'three shot detonator placer' which placed 3 dets several feet apart on the railhead in a single operation. These were used in areas of particular risk and according to the list I have were installed initially (c.1913) at about 18 locations on that Company's network.

 

Hope that's helped - sorry about the lack of pics.

[the penguin of doom]

See Mike.

 

2 points. 1), My memories better than I thought. And, 2), How quick were those replies??? B)

 

Now, can anyone say wether they were ALWAYS directly outside the signalbox or sometimes a little further down the line, depending on track layout around the 'box.

 

Cheers.

 

Sean.

[The Stationmaster]

See Mike.

 

2 points. 1), My memories better than I thought. And, 2), How quick were those replies??? B)

 

Now, can anyone say wether they were ALWAYS directly outside the signalbox or sometimes a little further down the line, depending on track layout around the 'box.

 

Cheers.

Sean.

 

All the Western ones I have known (about 50-60 'signalboxes) were opposite the 'box other than the 3 shot placers which by consequence of their reason for being there usually weren't opposite the 'box. I can't speak for the lesser Railways .

[Guest stuartp]

All the ones I can remember were directly outside the box, with the possible exception of Clayton West Junction where they were co-acting with (and therefore in advance of) the signal protecting entrance to the single line. That one was interlocked too, there were a couple of occasions where faults on the transient TCB equipment was cleared by the signalman beating the det placer (carefully) with a brake stick to get the release back.

 

The Duttons (?) frame at Barnsley Jumble Lane had stirrups, dunno if this was just a Duttons thing or not. The catch handles were on the front of the levers too. I only ever pulled them once, to attract the attention of a driver who had run past my red handsignal because he was too busy chatting to his cab guest. It was quite effective.

[mike knowles]

See Mike.

 

How quick were those replies??? B)

 

Sean.

 

 

Incredibly quick - many thanks to those who have responded.

Thinking about adding some to our club layout, might catch out the nerdy punters who revel in telling you somethings wrong/missing at the next exhibition

[mike knowles]

Just had a thought.

When I was a lad (yes I know a long time ago) I used to play at cowboys and indians and had a pair of guns which fired "caps". If these were still available, could I make the detonator placer on the layout work and so place a couple of caps on the line which would be set off as the train ran over them. A new one for the sound effects department!

(Or should I stop sniffing the thinners!)

[DavidBelcher]

CCH (the colour light signal people) used to offer a rather neat fogman's hut plus detonator placer (handwheel-operated) moulding in their 00 accessories range, don't know if it still exists.

 

David

[the penguin of doom]

Just had a thought.

When I was a lad (yes I know a long time ago) I used to play at cowboys and indians and had a pair of guns which fired "caps". If these were still available, could I make the detonator placer on the layout work and so place a couple of caps on the line which would be set off as the train ran over them. A new one for the sound effects department!

(Or should I stop sniffing the thinners!)

 

And you talk about nerdy punters at exhibitions???......

[beast66606]

Detonators could also work electrically, in conjunction with IBS for example.

[edcayton]

Irritable Bowel Syndrome? I suppose the bangs may have some effect.

 

Ed

[mikemeg]

Don't know whether this might help? Were detonator placers always outside signal boxes; no, not always.

 

Up to the 1960's, perhaps even beyond, there was a fogman's hut by shipyard bridge at Hessle Haven, which was around two hundred yards from Hessle Haven signal box. This hut had a detonator placer for the down main, just in advance of the down gantry which controlled entry into Hull's Inward Yard and the down main and down slow into Hull, though on this photo the down slow doll has been sawn off.

 

Sean still walks his dog on the site of this bridge. Anyway, here's a photo of the fogman's hut and the lever just outside for operating the detonator placer.

 

Cheers

 

Mike

[brian daniels]

Here is a set at Banbury coming out of the up bay.

[Oldddudders]

I was convinced that det placers were in use at the old box at Borough Market Junction, which used a Westinghouse Type K frame, but am unable to confirm this. http://www.wbsframe.mste.co.uk/public/Borough_Market_Junction.html and the links on that page may give an idea of just how busy this area was and certainly still is. With slow-speed running, overlaps were miniscule, and long trains could be stopped within just yards of each other, so det placers would seem a priority.

 

I think the signalman in that picture is Bert Murton, who transferred to London Bridge new box in 1976.

[beast66606]

Up to the 1960's, perhaps even beyond, there was a fogman's hut by shipyard bridge at Hessle Haven, which was around two hundred yards from Hessle Haven signal box. This hut had a detonator placer for the down main, just in advance of the down gantry which controlled entry into Hull's Inward Yard and the down main and down slow into Hull, though on this photo the down slow doll has been sawn off.

 

Mike - isn't that detonator placer for the distant though ?

 

These were frequently provided at such signals - and of course isolated distants. Saved the fogman having to fix detonators to the railhead when the distant was at caution and remove them when it was cleared - when a train would be approaching

[mikemeg]

Mike - isn't that detonator placer for the distant though ?

 

These were frequently provided at such signals - and of course isolated distants. Saved the fogman having to fix detonators to the railhead when the distant was at caution and remove them when it was cleared - when a train would be approaching

 

You're very probably right. I know only that this placer was here; I don't know enough about the signalling practice to say exactly what it covered and even though I spent quite a bit of time on this bridge c 1959 - 1963, I don't think I ever heard the detonators used.

 

Cheers

 

Mike

[craigwelsh]

Motor operated 3-shot detonator machines were installed at Cardiff by Westinghouse during the resignalling of 1933. They look very similar to the Banbury picture given earlier in the copyright photo I have. The operating machine is the same type as used on signals and the weight attached seems to default the machine to on. The picture is of a machine on no3 platform line though i'd have to see the signalling plan again to see how many were fitted overall and whether they are indeed annotated on the plan though I expect so.

 

In fact here is the quote from "Power Signalling at Cardiff G.W.R."

The working on the down main and No. 3 lines necessitates the home signals for these lines being fogged, and, to obviate the employment of fogmen, 3-shot detonator machines operated by motor have been provided, which place or take off detonators on these lines immediately ahead of the signals. The arrangements are such that the detonators stand normally on the line and are removed by the changing of the signal from red to green.

To prevent their replacement, should the signal be put to danger before their position on the line is clear, they are controlled by the short track circuit immediately ahead of the signal. They also give a warning should the driver overrun these signals at danger.

 

Has anyone modelled one before?

[The Stationmaster]

Mike - isn't that detonator placer for the distant though ?

 

These were frequently provided at such signals - and of course isolated distants. Saved the fogman having to fix detonators to the railhead when the distant was at caution and remove them when it was cleared - when a train would be approaching

 

Fairly definitely for the distant I would say noting there isn't one on the line nearest the Fogman's hut. And the placer is clearly in rear of the signals - which was the normal procedure at a Distant Signal.

[The Stationmaster]

I was convinced that det placers were in use at the old box at Borough Market Junction, which used a Westinghouse Type K frame, but am unable to confirm this. http://www.wbsframe.mste.co.uk/public/Borough_Market_Junction.html and the links on that page may give an idea of just how busy this area was and certainly still is. With slow-speed running, overlaps were miniscule, and long trains could be stopped within just yards of each other, so det placers would seem a priority.

 

 

Ian, I have read elsewhere about the use of detonator placers at Borough Marke Jcn but can't find anything to confirm that. As the frame is preserved at the NRM there might be something there which would give a definite answer?

[LNERGE]

I have a couple of Clayton fogging machines. I'll post some pictures later if anyone is interested..

[mikemeg]

Fairly definitely for the distant I would say noting there isn't one on the line nearest the Fogman's hut. And the placer is clearly in rear of the signals - which was the normal procedure at a Distant Signal.

 

Let me ask another question. Up to around a year prior to this photo being taken, there was another doll on this gantry, configured similarly to the down main doll, for the down slow, which also had a distant on it. Would this distant have also been detonator protected at the same point; so would there have been two levers outside this fogman's hut?

 

I ask this because though I've modelled the fogman's hut on my Hessle Haven layout, I haven't yet modelled the detonator placer(s).

 

Cheers

 

Mike

[Chris116]

I know this may be a bit of the OP but didn't Triang used to do a Fogmans Hut which caused a bang when the train went past?

 

Chris

 

UPDATE

 

I have just answered my own question. I went to the Triang Railways Site and sure enough RT267 is a Fog Hut. It worked rather like a mouse trap with a lever being set and the train hitting a second lever which caused the first sprung loaded one to release and hit the toy gun cap that was used to make the bang.

[LNERGE]

Let me ask another question. Up to around a year prior to this photo being taken, there was another doll on this gantry, configured similarly to the down main doll, for the down slow, which also had a distant on it. Would this distant have also been detonator protected at the same point; so would there have been two levers outside this fogman's hut?

 

I ask this because though I've modelled the fogman's hut on my Hessle Haven layout, I haven't yet modelled the detonator placer(s).

 

Cheers

 

Mike

 

It may not have had a lever as the fogman could remove and replace detonators by hand. If there was a slow moving train on the near line he would not be able to do the same on the far line, hence the lever operated detonator placer.

[mikemeg]

It may not have had a lever as the fogman could remove and replace detonators by hand. If there was a slow moving train on the near line he would not be able to do the same on the far line, hence the lever operated detonator placer.

 

Many thanks for that, one lever and detonator placer it will be on the model.

 

Cheers

 

Mike