Model Railway Forum banner

4mm scale Signal wiring

7947 Views 21 Replies 6 Participants Last post by  Lancashire Fusilier
Hi All,

Just in the process of building my first ever MSE semaphore signal kit and will be electrifying the lamp via an LED to make it operate.

As such I appear to have a couple of options concerning the wiring.

I was originally planning on hiding one wire down the middle of the tubular post which is easy to do and making the rest of the signal live and that would be the + and - I would need to power the LED. If using a lightly filed shaped and painted 1.8mm mini or panel dot type from DCC Concepts I was planning on using one of the legs to form the lamp bracket and solder it directly to the post meaning just one wire needed to be run through the tube.

No real problems there except the drilling of the hole in the side of the tube to accept the wire but all quite achievable really.

I was wondering though, when I make my white metal cast "timber post" signals then this is not really an option and the wire would need to be run down the outside of the signal post.

Then I actually saw signal posts that did have a cable in real life running up the post, probably to power the lamp in later days 1930s on perhaps? and as such I am wondering if it would be more prototypical to actually run the cable neatly up the post and secure with a dot of superglue (CA) here and there. If so should I paint the cable all one colour, use the colour insulation to match prototypical cable colours, assume a conduit was used to run the cable, or what??

By the way I am using the nice single strand 30swg or 0.25mm diameter wire with insulation making it 0.5mm in total or a scale size of 1.5" in diameter, not a totally ludicrous size if it was considered to be a scale conduit however I could strip all the insulation off it and use it bare, against a well painted post for insulation purposes, painted black or appropriate weathered colours, giving a scale size of 19mm - all very realistic I would have thought for a conduit diameter.

Thoughts, comments, suggestions, ideas please.
See less See more
1 - 20 of 22 Posts
Dependant upon the date your model is based on an LED would be far too bright - oil lamps were very dull and when the spectacles got dirty they got even duller - until the lamp man gave them a wipe on his rounds.

The general proposals for powering the lamp look good though.

Some very early signals were gas lit which gives another excuse for a "wire" down the side
QUOTE (beast66606 @ 13 May 2008, 18:33) <{POST_SNAPBACK}>Dependant upon the date your model is based on an LED would be far too bright - oil lamps were very dull and when the spectacles got dirty they got even duller - until the lamp man gave them a wipe on his rounds.

The general proposals for powering the lamp look good though.

Some very early signals were gas lit which gives another excuse for a "wire" down the side

***With 12v and between 12 and 15k the LED will be just fine - Several of the best Pro builders in the UK do just that, as do eveyone else I know who makes signals.

The best way to try the reistor value is to buy a 20K linear potentiometer. Put a ik resistor in series with it as a "safety net".

connect it in series and twiddle the knob until you have the light level you want, then take away the power and measure across the potentiometer terminals. Just use the nearest (next highest usually) standard resistor value and you are done!

with a high value resistor it will be limited to a milliamp of so as will barely glow. If its still slightly bright paint the lens with a mixture of clear varnish containing a very little black and orange - it softens the colour even more and gives a smoky tint thats actually rather neat.

for the wire find a dead motor - old shaver, dead model railway motor etc. the motor winding wire is super thin (hair sized sometimes) and is enamel covered. You'll need to strip off the enamel of course to solder to it - use a strong solvent.

Option - I sell a silver loaded paint - Martin71 has an image on forum somewhare showing a lamp in the hand of a 4mm scale guard - he painted the wiring onto the figure with the silver loaded paint then painted his clothes over it when it was dry - totally invisible.

BTW - paint the LED all over white or spray with standard gray car undercoat...(it reflects light inwards and helps reduce leakage better than a black base coat) then paint the final colour on top of that. to make the clear lens, file across the face of the 1.8mm microdot and you'll get a perfect round shape - much easier than painting it neatly :) :)

Regards
Richard
DCCconcepts
See less See more
Some signal lamps were electrically powered, but often oil-lit signals have wires running up the post to connect to a switch indicating the arm position back to a repeater in the signalbox and also connections to a bimetal strip in the oil-lamp - if the lamp flame failed and went out, the bimetal strip cooled down and broke a circuit which then alerted the signalman that the lamp had gone out. Such devices were in use from around 1850/60 onwards, so wires on signal posts are truely prototypical.

Regards,
John Webb
QUOTE (John Webb @ 13 May 2008, 20:26) <{POST_SNAPBACK}>Some signal lamps were electrically powered, but often oil-lit signals has wires running up the post to connect to a switch indicating the arm position back to a repeater in the signalbox and also connections to a bimetal strip in the oil-lamp - if the lamp flame failed and went out, the bimetal strip cooled down and broke a circuit which then alerted the signalman that the lamp had gone out. Such devices were in use from around 1850/60 onwards, so wires on signal posts are truely prototypical.

Regards,
John Webb

*** I didn't know about that bi-metal strip John - thanks for the very interesting bit of Information!

Richard
DCCconcepts
My pleasure. Basically the 'lamp out' detectors were fitted to any signal out of the direct sight of the signalman so that he knew for certain all his lamps were OK. Particularly applied to distants which could be up to around 1,500 yards away, or where bridges or tunnels restricted his view.

Regards,
John
QUOTE With 12v and between 12 and 15k the LED will be just fine - Several of the best Pro builders in the UK do just that, as do eveyone else I know who makes signals.

Be interested to seem some photos of those - from my observations most model signals are far too bright, whoever makes them, and as I photographed probably the best part of a thousand prototypes I have seen one or two of the real thing.
See less See more
QUOTE (beast66606 @ 13 May 2008, 23:04) <{POST_SNAPBACK}>Be interested to seem some photos of those - from my observations most model signals are far too bright, whoever makes them, and as I photographed probably the best part of a thousand prototypes I have seen one or two of the real thing.


***I haven't any installed yet but when I do I'll take a photo - the LED is really only just adequately powered to turn on... they are pretty well invisible as far as light is concerned in daylight, with a soft glow in softer light - I too know what they should look like!

Bear in mind they DO in reality have to be very slightly brighter than the original of they'd never transmit through the spectacle at all on a model!

Not quite the same thing, but here are a couple of led images taken with the lights off early in the development of my loco lamps on a part finished model - even though they are still totally bare LEDs you'll notice there is not enough light to illuminate the buffer beam - and this is before the tinted epoxy (smoky amber/yellowish) lenses are added in front of the tiny 0.8mm LEDs - once finished, they are indeed like paraffin or oil lamps. The resistor in this case is 14k from memory

Richard
DCCconcepts
See less See more
Of interest to those who are building UK mechanical signals... The real semaphores often have two or more cables running up their posts and in the main certainly one cable.
The first and main cable is there for arm proving - On/Off repeater back to the controlling signal box and used further in the interlocking.
The second, and not always present cable, is where the illumination style has been modernised to electric lamp illumination over the former oil lit lamp and the cable provides power to light the lamp. Some posts will have more cables where they have more arms on them to be proved.
So seeing a fine wire/s running up the post would be quite acceptable.
See less See more
QUOTE (Brian @ 13 May 2008, 16:29) <{POST_SNAPBACK}>....So seeing a fine wire/s running up the post would be quite acceptable...

If the signal was close to the 'telegraph' poles at the side of the line, the wires would sometimes be run from the nearest telegraph pole to a pair of insulators mounted near the top of the signal and make their way down the signal for a short distance rather than up. But as most of us don't include working telegraph cables particularly at 4mm scale....


Regards,
John Webb
See less See more
QUOTE (John Webb @ 13 May 2008, 22:52) <{POST_SNAPBACK}>If the signal was close to the 'telegraph' poles at the side of the line, the wires would sometimes be run from the nearest telegraph pole to a pair of insulators mounted near the top of the signal and make their way down the signal for a short distance rather than up. But as most of us don't include working telegraph cables particularly at 4mm scale....


Regards,
John Webb

Hi .
Some telegraph poles had cable stays to keep them upright . If modelled these could be used.
Regards ,
Tony
See less See more
Thanks for all the input. I see that using the wire would be fine and prototypical then running up the side of the post so will give it a go and see what it looks like. I was planning on using a trimpot for the adjustment of the LED brightness actually and leaving it in place as I don't think they are very expensive but obviously more so that a fixed value resistor.

I was also thinking about whether any light is emitted out of the back of the LED. From memory I dont think there is any but was going to file a small dot so that the back blinder would work in the sense that when on the little light at the back of the lamp would show.
As John says most cables, in the "early" days would use the pole route rather than down the post for light in/out indication.

Richard, you LEDs look good but a bit white I assume your comments about masking them will be applied.

QUOTE The first and main cable is there for arm proving - On/Off repeater back to the controlling signal box and used further in the interlocking

Out of all the signals on the railway VERY few (comparatively) were repeated in the boxes, most "interlocking" - actually releases - was done by the lever position, so HNC (home normal clearance) was proved through the lever, the arm could actually be stuck off - it was down to the bobby to observe the actual signal before pegging up, hence the back blinder which obscured the lamp when the arm moved.

Distant signals were the most common to have the arm repeated and the block release tied into it showing danger/normal - and as stated elsewhere most layouts don't have the room for an isolated distant, it would need to be approx 40' in front of the home, combined home + distant signals often only repeated the distant slot not the arm so again the slot could be normal but the arm stuck off and hence no wire up the post.

Which part of the LMS are you modelling L.F ?
See less See more
QUOTE (beast66606 @ 14 May 2008, 17:19) <{POST_SNAPBACK}>Richard, you LEDs look good but a bit white I assume your comments about masking them will be applied.

*** As I noted the image was to show you that an LED can indeed be attenuated to the point that it has the correct level of light. The white balance of the camera was still set for some product photography rather than natural light so that + the slow time of that exposure made them look whiter than they really are (they are actually golden/prototype white) however as I noted in the same post, they were also photographed without the lens which I also add/make from tinted epoxy being applied to them - they look exactly like an oil/parrafin loco lamps softer tint when its in place.... I am very particular about such things

Richard
DCCconcepts
While I think about it...

at the time of the grouping there was a really unusual signal at one end of Ribblehead - two arms on the same post but most unusually, one facing in each firection on opposite sides of the post. I presume it was done that way by the Midland because of sighting needs but it was a rare and very non standard sort of arrangement. The LMS replaced it not all that long after but I'd like to model it as it still was in 1928.

Does anyone have any good images of that signal? The only ones I can find so far are very much in the distance and not good enough to calculate height and detail well enough to satisfy me.

(For that matter I'd be grateful for any added detail or signalling diagrammes for Ribblehead stn, Blea Moor, Settle and Stainforth boxes as I'd like to recreate the original signalling + original box diagrammes on the computer screen I'll be using for each of those places on the layout - the layout will in fact be touch screen controlled from those diagrammes)

Regards

Richard
See less See more
QUOTE (Richard Johnson @ 14 May 2008, 16:02) <{POST_SNAPBACK}>While I think about it...

at the time of the grouping there was a really unusual signal at one end of Ribblehead - two arms on the same post but most unusually, one facing in each firection on opposite sides of the post. I presume it was done that way by the Midland because of sighting needs but it was a rare and very non standard sort of arrangement. The LMS replaced it not all that long after but I'd like to model it as it still was in 1928.

I'm sure it survived well into BR days

QUOTE Does anyone have any good images of that signal? The only ones I can find so far are very much in the distance and not good enough to calculate height and detail well enough to satisfy me.

I've seen a close up of it in a book but can't for the life of me remember which one - might be the Anderson/Fox one below.

QUOTE (For that matter I'd be grateful for any added detail or signalling diagrammes for Ribblehead stn, Blea Moor, Settle and Stainforth boxes as I'd like to recreate the original signalling + original box diagrammes on the computer screen I'll be using for each of those places on the layout - the layout will in fact be touch screen controlled from those diagrammes)

Have you tried the Fox/Anderson book Stations and Structures of the S&C ?

Blea Moor is an LMS box so potentially you could be looking at the old Midland structure - again I've seen photos but can't remember where.
See less See more
By coincidence I got the V R Anderson & G K Fox book "Stations and Structures of the Settle & Carlisle Railway" at a reduced price at Geoff Gamble's book stand at the SW Herts MRE last Saturday. (ISBN 0 86093 360 1, OPC, first published 1986, reprinted 2000)

Ribblehead
The double-armed Distant signal at the N. end of Ribblehead Viaduct is shown very clearly in Plate 44.
Track layout from Midland surveys of 1874 and 1913; signal diagram from 1967 information.

Blea Moor
There was a Midland signalbox from 1892 to 1941 - there is and end-on view in Plate 47.
It was replaced in 1941, when the sidings were extended and made into loops, with a brick and timber LMS box. This is pictured in close-up in Plate 49.
Track layout from 1913; signal diagram from 1962 information.

Settle (Station)
Track layout from a 1926 LMS plan; signal diagram from 1963 information.

Stainforth Sidings
Track layout from 1913 survey; signal diagram from 1963 information.

Roger Sivitar's book "The Settle to Carlisle - A Tribute" (Baton Press, 1984, ISBN 0 85936 293 0) has some lovely if more modern photos.

Hope the above is of help.
Regards,
John Webb
See less See more
QUOTE Stainforth Sidings
Track layout from 1913 survey; signal diagram from 1963 information.

Which is actually the 1950 BR cabin so beware
See less See more
QUOTE (beast66606 @ 14 May 2008, 17:19) <{POST_SNAPBACK}>Which part of the LMS are you modelling L.F ?

Very loosely based on Matlock Bath and Matlock area simply that my house here in Perth is Namsed Hightor and I saw that was near Matlock and part of the old MR area. Yes, before going further it is likely that these would have been all timber posted lower quadrant thingamebobs but there you go
See less See more
Sorry to interupt your thread here Richard however I had great success last night in filing down the 1.8mm LED on the lens and on the top of it then I cut of the top of the MES Adlake lamp casting and CA glued it ontop of the LED and let that go off. I then soldered the bracket to the signal and used the lower leg of the LED (can't remember if it was the cathode or anode) to solder the LED to the bracket providing a solid mechanical and electrical connection. Then soldered some of your very fine wire (name escapes me but it came with the 0.8mm LEDs) to the upper leg and trimmed the leg off as close as I could.

Hooked it up to 5 volts with the supplied resistor and it was all working very well indeed first go thank you very much!

I will secure the wire down the side of the post I think, probably the left hand side or the rear I would imagine. I have photos but don't know how to post them on this forum. I will have them up on other forums shortly.
1 - 20 of 22 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top