Points, rodding, signals, cables, ground frames and boxes ???

Why try six posts when one will do ;-)
Back in the days when men were men and engines were black with "Lancashire
and Yorkshire" (Or at a pinch Great Western) painted on the side signalling
took a lot of pulling and pushing does anyone know (pretty please) ...
How far a set of points could be from the lever controlling it, that is
taking into account all the rodding the signal man had to shift when he
pulled on the lever?
If cranks etc are introduced (to change the direction of the pull) to the
above, how much reduction in distance would there be per crank (if any)?
Did the frames to be found in signal boxes give any mechanical advantage
over a lever on a ground frame, if so by how much?
Was there a typical maximum number of levers that would be accommodated on a
ground frame before they just gave up and built a box(*) instead?
(*
) I'm thinking in terms of a large yard and I appreciate that technically
a signal box in a yard isn't a signal box as it doesn't control a box
section ;-)
Signals? As a rough estimate, assuming they are operated by cable how close
would they have to be to a signal box?
Would facing point locks be required in a yard (no passengers)?
... and one last question, narrow gauge this time, did any narrow gauge line
(around 2' 6" gauge) use fully signalled block sections?
Many thanks ...
Reply to
Chris Wilson
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"Chris Wilson" wrote
I didn't realise that there were black engines with 'Great Western' painted on the side? ;-)
John.
Reply to
John Turner
Chris,
There were limits for pointwork and signals which I can dig out when I get home later today.
I'm not sure what you mean by the question. :-) Apart from changing direction, various forms of crank were used to compensate for expansion or contraction of the rodding due to heat (or cold). The basic idea was to get the same length of rod pulling and pushing in the run to set of points so that when rods changed length, the effect of those in compression was cancelled by those in tension - and vice versa. It could be possible to arrange this with the normal crank work in the run to a set of points, but it was often necessary to insert compensating crank arrangements in a long run to arrange a balance between pushing and pulling - that could be the arrangement of two cranks close together with a short link between them purely to reverse the direction of movement.
I think that would generally be the case since a ground frame was normally quite close to the pointwork it controlled and there would be less effort required to operate the short rodding length.
I think there might also have been a form of health and safety at work as well - i.e. the levers in a box could be worked regularly and often, and having longer levers with larger moments would make life easier for the signalman, whereas ground frame work was occasional.
I'm sure there will be many examples to prove and disprove theories :-) I do remember the signal box at Dalmally on the C&O line to Oban where the signal box on the platform was virtually a ground frame since the block and token instruments were actually in the station building.
But I'm sure that a lot of the decisions as to whether there should be a ground frame or not would be down to commonsense. If you didn't want your signalman having to operate pointwork for shunting operations on an occasional basis, then you would provide a ground frame interlocked in some way to the nearest signal box. If the workload was such that it merited almost continuous operation by a man, then you put a roof over his head and called it a signal box :-)
See above - there was a limit. I think it was 200 yards for a signal, but I can confirm that later. Also, the limit for signals was not purely down to the limits imposed by the mechanics of the system - the signalman also had to be able to see all that was going on before the days of track circuits and remote indication, so the actual limits might be closer because of obstructions to his sight line - probably more prevalent in city and suburban settings.
FPLs were normally only required on pointwork carrying passenger services, so would not normally be used in a yard.
Pass, but I think I remember the Isle of Man railway having a pukka signalling system :-)
Jim.
Reply to
Jim Guthrie
You know what I meant :-(
Anyway according to Russell there were some GWR engines painted black. They were some of the ex-ROD 2-8-0. Some were refurbished and got the full paint treatment, however many of the ones they (the GWR) got were so clapped out it wasn't worth spending any money on them, so they were painted black and run in to the ground 'till they curled up their toes
Nah-nah nah-nah-nah :-)
Reply to
Chris Wilson
"Lancashire
Cheers Jim, re the above, obviously it takes effort to shift a length of rodding, the more rodding the more effort hence the distance limit. Now if we introduce additional mechanical actions in to the rodding - such as cranks. Carrying out additional mechanical actions requires additional mechanical effort so if follows that if a signal man could shift a rod "x" yards long with "n" cranks in its length if "n" was increased then "x" must be decreased.
Been through all my books on signalling - which admittedly isn't all that many and I still don't have a solution for "x" though.
FWIW I'm trying to work out if the standard gauge station on my new layout is going to need 1, 2 or even 3 signal boxes. (Oh and if I can justify one at my narrow gauge stn).
Reply to
Chris Wilson
"Chris Wilson" wrote
black.
I suspect there were more than just the ROD 2-8-0s at various times, particularly during the two world wars.
John.
Reply to
John Turner
Yes, certainly for the last one, apparently though during the first big one the GWR simply did away with lining, used a cheaper less shiny green paint and painted over the brass bits, doesn't really effect me as I've now narrowed down my period to 1921 - 1928 (ish) on a L&Y secondary route, so I can run 3 "mini periods" L&Y, L&Y + LNWR, L&Y, LNWR, MR and LMS.
I am *so* going to have to scale things down though. I thought that I'd finished planning last night and so I started to add up how much it would all cost me (with a view to buying things in phases as I go along) ... just track at this stage ... for the 009 section alone I counted *46* sets of points. I fear that I'm going to have to go though a period of pre-build rationalisation.
Reply to
Chris Wilson
"Chris Wilson" wrote
Currently the only model loco I own of GWR origin is a 14/48xx 0-4-2T which has various bits of Airfix, Dapol and Hornby origins, plus a few more besides, sits happily in early BR unlined black livery, and very fetching it is too. Makes me want to add one of the new Bachmann Halls in BR mixed-traffic black livery, which I certainly think is the most attractive of the current offerings.
John.
Reply to
John Turner
My grandfather was the signalman at Hayfield, Derbyshire for many years. Although it's now over 40 years ago I recollect that at least one of the signals (the distant just before Slacks Crossing) was over 800 yards from the box and as it was not visible from the box there was some sort of indicator showing whether the signal was pulled off or not.
Reply to
Bruce Fletcher
In message , Jim Guthrie writes
There are examples of working (i.e. not fixed) distant signals being 1000 yards away from the signal box and out of the sight of the signalman.
Example: Aberaman Station (T.V.R.) down distant.
Reply to
Jane Sullivan
The Ministry of Transport Regulations set 350yards as the limit of manually worked points, this is also virtually the practical limit. Ponits located further away than this would be motor operated and have a shorter lever in the frame to remind the signalman that the lever would move easily. No limit is mentioned in my reference for signals, but there is a comment that "...may be located as much as 2,000yds from the signal box...".
Source is Mechanical Signalling Equipment (British Practice), published by The Institution of Railway Signal Engineers.
Reply to
John Shelley
The "signalbox" at Hayling Island was little more than a ground level shed covering a ground frame. About six by eight feet IIRC.
-- Cheers Roger T.
Home of the Great Eastern Railway
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Reply to
Roger T.
In later years, 350 yards IIRC. In the early days of interlocking, 150 yards I think.
-- Cheers Roger T.
Home of the Great Eastern Railway
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Reply to
Roger T.
The Lynton and Barnstaple seemed to have a reasonable amount of signals in the photos of the line. While refreshing my memory on this I came across this site.
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G.Harman
Reply to
g.harman
ISTR that the GWR had "manual" electric points where the signalman wound a hand powered dynamo to provide the power.
No idea of how it intergrated with the various levers though or wether other Railway companies had a similar device.
G.Harman
Reply to
g.harman

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