31A S&T

[31A]

Bored with having non-working (mainly colour light) signals, coincidentally I was clearing out a kitchen cupboard and came across a large number of chopsticks! They must have been bought (or donated) in a fit of optimism many years ago as I'd never been able to use them for eating food, but looked at in a new light they represented a supply of model railway timber, not dissimilar to signal posts. Presumably they're made from bamboo; I set about whittling one using a variety of tools to see what could be done. The wood is very hard to work, but on the plus side, good for drilling holes into.

 

I'd built several signals previously using etched parts, for a previous layout, but that was over 20 years ago so I decided to start with something relatively simple to re-learn the techniques involved. One of the signals on the layout would control the exit from the Up Siding (headshunt), giving access to the Dock platform, Platform 1, Middle Siding, Platform 2 and Platform 3; in other words, there are five possible routes from it. In order to economise on levers, I decided to use a single arm signal with a (non working) five way route indicator. Looking through various books, I found something similar at South Lynn in "Aspects of East Anglian Steam - Volume Two" (J. D. Mann, South Anglia Productions, 1991), also visible to the right of this picture:

 

https://transportsofdelight.smugmug.com/RAILWAYS/BRITISH-STEAM-LOCOMOTIVES/MIDLAND/i-4hBHRpC/A

 

Thanks to the information received from LNERGE and others in response to this query

 

http://www.rmweb.co.uk/community/index.php?/topic/115192-south-lynn-signal-query/

 

it became apparent that the real one isn't quite what it at first seemed, as there is a disc at the foot of the post and three of the five routes relate to the disc signal rather than the semaphore arm, on the post of which the route indicators are mounted. Nevertheless I made a non-working mock up from Ratio plastic parts.

 

 

The driver's eye view in the above picture is not normally seen on the layout as it faces an overbridge; hence the route indicators can be non working.

 

To start the working model, I carved a piece of chopstick to the size of a 15ft. signal post. I made up an assembly including a lamp bracket and arm bearing, joined together on one strip of brass, analogous to the similar part in the Ratio kits. The vertical strip that joins the bearing and the lamp is virtually invisible on the finished signal, between the arm and the backlight blinder. The lamp is an MSE casting, and the arm comes from an old MSE etch (these have now been replaced in the Wizard Models range by finer items originally from D&S). The bearing / lamp assembly is attached to the post by two dressmakers brass pins, with their heads filed flat and passed through two countersunk holes in the post. The other metal fittings were attached to the post in similar manner.

 

 

I then made up a bracket for the route indicators. The flat part is brass etch scrap, again soldered to dressmakers pins passed through the post, and the supporting framework is a finger singeing exercise in 1mm N/S strip.

 

 

 

 

Thanks again to LNERGE who provided a lot of information regarding the route indicators.  I made them up from two laminations of 60thou Plastikard, with the hoods from the thinnest metal I could find - from a metal drinks can; aluminium I believe.

 

 

Although the route indicator was to be non working (and not usually visible from the front), I thought I ought to try and represent the face of it somehow. After several false starts (involving bow pens), I drew up a grid in Word to represent the frames and printed it onto overhead projector transparency material. It is backed by a piece of grey paper, and glued onto the front of the route indicator assembly. Here's the finished post.

 

 

The ladder is a flat etch (actually in a D&S packet, but now I believe available from MSE), with the stiles thickened up by soldering 0.45mm brass wire down them and then filing flat. I had intended to put a crank at the base to attach the subterranean mechanism to, but there wasn't really room beneath the weight bar position so I've put a cosmetic wheel there instead. The bracket is from the D&S Signal Post Fittings etch (now MSE) and the wheel is from an old MSE etch of point rodding fittings. I decided a 'ball and spike' finial would be quite vulnerable at the front of the layout, so the post is topped with a pyramid post cap from the MSE range.

 

Having painted and glazed the arm, I fixed it in place by carefully soldering the backlight blinder in place, and attached it to the weight bar with a length of 5 amp fuse wire. The weight bar itself is again from the Signal Post Fittings etch, made more robust by sweating two together and soldering washers either side of the pivot hole. Here's the finished signal.

 

 

 

And planted on the layout; driver's eye view (or almost so) of the side which isn't normally visible. The base is recessed into the cork underlay so that the top is flush, and attached to the baseboard by a 6BA bolt into the tapped hole in the base. The base will be disguised properly once I've made the under board gubbins that work the signal!

 

 

And the reverse side, which is the side usually seen by layout operators. I'm not sure why the camera makes it look as though the arm hangs inwards from the top, as this isn't apparent to the naked eye. The passing motive power is a nod to the South Lynn inspiration! The non-working colour light will be the next to be replaced, by a gantry with three dolls and six arms!

 

 

 

 

[LNERGE]

Magnificent.

[31A]

Magnificent.

 

Why thank you kind sirs!  Hopefully something more complicated to show before too long.

[31A]

Having practiced with something simple, my next signalling project goes to the opposite extreme!  The (dummy) colour light signal in the picture of the 4MT is the Inner Home giving access to three of the platforms at Finsbury Square station, and has only ever been a 'place marker' until I could replace it with working semaphore signals.  So, I've raided the S&T stores and come up with a D&S Models Great Northern Railway signal bridge kit, and two lattice base posts (these parts are now available from MSE).  However the parts in the D&S kit only provided the basics, and no instructions.   Despite studying as many photos as I could find (mainly of the gantries in the Belle Isle area outside King's Cross of which I found several close ups) I was struggling a bit over dimensional aspects.  Thanks to the generous help of Mick Nicholson of this parish, I now have enough information to give it a go.

 

To start with, I made up the lattice base posts, but added corner reinforcements from 1mm brass 'L' angle, which I think improves the appearance, and also makes the posts stronger.  Then turning again to my supply of chopsticks, I made three doll posts.  Whereas it had been relatively simple to make a post for the last signal from one of these, making three consistently was more difficult.  Luckily each chopstick is long enough to make several doll posts, and I've got a good supply!  As before, arm bearings and lamp brackets were made from brass and secured to the wooden posts by passing pins through holes in the post, and soldered to the brass components.  Lamps are glued to the brackets with cyano, which brings us to this stage:

 

 

Using the information Mick supplied, it appeared that the decking for the bridge need to be 3' 6" wide (14mm in 4mm scale) whereas the brass component was more like 22mm wide; I think this was one of the reasons I had difficulty coming to terms with the dimensions.  To make the bearers which run from side to side of the bridge supporting the decking, I was going to use 1.5mm square brass which is close to scale size for those on the real signals.  So I soldered one length of square brass under the strip to one side of the etched component, then soldered the other strip in the position for the narrowed decking, 12mm apart rom the first one.  Then cut away the surplus from the overhanging edge of the decking etch.  This has made a surprisingly strong 'top' to the bridge which should help to make the finished signal quite robust.

 

The dolls wil fit into sockets made from pieces of 4mm OD square brass tube soldered into the top of the left hand base post, and between the bridge sides. This should mean that I'll be able to finish the dolls before fitting them into the bridge.  The picture below shows progress so far, with the left hand half of the bridge now soldered to the left hand base post, and the doll sockets soldered in position.  The other components are not yet fixed together but have just been placed in position for the photograph.  The right hand doll looks a bit wonky, but at the moment is a loose fit in its socket - this will be rectified in due course.  For the moment, I've deliberately left the corner angles on the base posts long at the bottom as I'm considering whether to let them into holes in the base plates to make a stronger construction.

 

 

 

 

[31A]

Today I'll be mainly drilling 28 x 0.5mm holes round the edges of the deck for the handrail stanchions!  Seemed sensible to do this while the deck can still be worked on 'in the flat'.  Thanks to Eileen's Emporium for swiftly delivering another supply of drill bits; I wonder how long they'll last.

[28XX]

It will depend how impatient you are

[31A]

I managed to break one of the new drills.

 

On offering up the bits so far, I was surprised by how tall the signal was going to be; so much so that it seemed to dominate the layout!  The base posts worked out at 23ft tall, so I suppose allowing for rails and ballast that would make the platform about 20ft above rail level.  In place on the layout, it would need to be 'sighted' by drivers of trains approaching under an overbridge.  Looking at the pictures of signal bridges outside King's Cross, some of them seemed to barely clear the loco's chimneys.  I managed to balance the pieces together in situ on the layout, and a Sighting Committee was convened.

 

 

Actually the driver's eye view of the signals from beneath the bridge was better than I expected, but note how much taller it is than the colour light on a Ratio post that it will replace; also by how much it clears the locos standing under it.  Mick Nicholson told me that several LNER signal bridges were built with their decks 17ft above rail level, so I made a lash up which would simulate this dimension.  This puts the bottom of the girder about 14' 6" above rail level, so still outside the loading gauge.

 

 

 

I think that gives a better proportioned result - would be interested to know what others think.

 

The snag would be that I'd have to shorten  the base posts that I've just put together!

 

[micknich2003]

Steve, the original drawing I sent you shows the top face of the decking boards to be 20ft 4in above rail height.

 

 The 17ft above rail height dimension ref to the later "Plate and Angle bracket signals as per attached photo'.

[31A]

Thanks Mick, that's interesting - obviously the 'plate and angle' brackets had less depth of girder beneath them.  I think I prefer the proportions of my 'mock up' though.  I'll do some more measuring!

 

The D&S base posts work out at 23' tall but they're probably a model of the complete post which allows for greater depth of track bed and ballast up from ground level, which if modelled correctly might well put the deck at about 20' above rail level.  Whereas on my model the bottom of the posts is level with the bottom of the Peco sleepers (I'll recess the base plates into the cork underlay so that the tops are flush), so that probably puts the top of the deck about 22' above rail level if made up as supplied.

 

Cutting it down to give a deck height of 17' as per my mock up with the steel rules does look OK though, given that the signals would have to be sighted from under the bridge.  In fact I wondered whether the gantries at Belle Isle were deliberately low to allow better sighting through the tunnels.  There was a tall gantry at High Dyke which is visible in quite a lot of steam age photos published in albums etc, which does look quite a bit higher above rail level.

[31A]

Various things have got in the way of railway modelling over the past couple of weeks, and I'm still pondering various aspects of this signal.

 

I've not really come to terms with the height of it (but think I have a way forward); I think the dolls (and hence the main posts and lattice girders) will have to be set back slightly further than scale in relation to the decking otherwise the pull wires won't be able to pass behind the handrail stanchions; and I think the pull off wires will have to go towards the right hand side of the gantry rather than the left.  This is because the left hand post will be in the six-foot between the Up Main and the Loco Spur (and these are on a curve), and there won't be clearance for the balance weights and connections to the 'underground' mechanisms.  This means the pull wires for all six arms will have to pass through cranks, whereas I'd originally thought that 2 of the 6 would be straight pulls.  It also means the 'underground' mechanisms will have to be towards the back of the layout where they're less easy to reach!

 

Anyway, I haven't been idle, and have prepared the arms for the signal.  Here they are, temporarily mounted on the dolls, and the dolls are temporarily mounted on half of the gantry.

 

 

I don't like to see semaphore arms standing at strange angles, especially when 'on', so I've come up with a way of incorporating a 'clutch' between the arm and the bearing tube.  A small slice of the same tube is soldered behind the arm, with most of its length filed to a semi circular section.  The end of the bearing tube is also filed to a semi circular section and the two interlock holding the arm horizontally, then the end of the bearing tube is filed off to an angle, allowing the arm to pull off to 45 degrees.  Hopefully these pictures explain better than my words!

 

 

 

 

This arrangement is quite fiddly to set up but once done, is unobtrusive.  It does make it quite difficult to get the arms close to the posts, but having said that I need to allow clearance behind the arms for the eventual spectacle glazing.  It also means that each arm then is unique and matched to its individual bearing, so I've identified them to the dolls they belong to with stripes of white paint on the rear.  The backlight blinders will need to be soldered quite 'tight' to the rear of the bearings so that the arms are held in place for the clutch to work properly.

 

 

 

[31A]

We now have a signal bridge!

 

 

 

The posts are straight and parallel with each other, despite the camera trying to make it look otherwise!  I must have managed to make it up quite squarely as it will balance on its own feet with no support.

 

In the end I set back the transverse girders from the front of the deck by slightly more than they should have been, to give clearance for the pull wires between the fronts of the dolls and the handrail stanchions.  Hence as well as the 1.5mm square brass that I used to represent the deck bearers, I've soldered another length of the same between the front girder and the front bearer as a spacer and to provide a strong joint between the girder and the deck.  This has helped make a surprisingly strong structure!

 

I think the decision to take the pull wires to the right hand end rather than the left will make arranging the cranks easier, as they will be remote from the dolls.  However I'll have to think of a way of getting the down wires through or past the deck; I think on the real ones they just pass through the slots between the deck boards, but I think I'll have to make openings to provide clearance for the model to work.

 

[31A]

Not much railway modelling happened here during December with one thing and another, but since the turn of the year things have started to happen again.

 

Having pondered over how to arrange the cranks and pull wires, in the end I've gone for two groups of three balance levers, on either side of the right hand main post.  Hence there are two groups of three cranks at the top of this post.  I decided I'd have to cut holes in the deck to allow the wires to pass through so, to avoid weakening the structure of the bridge, the left hand group of cranks is set 'inboard' and the pull wires from these will pass between the girders of the bridge.  The wires from the outer set pass through the front edge of the deck.

 

 

I then made up two groups of three balance levers.  I prefer to laminate two pieces from the MSE Post Fittings fret for strength, but in this case I also need to allow clearance for the connections in between the levers, so the outer ones are only double thicknesses as far as the pivot point.  I hope this proves strong enough!

 

 

After a false start, I've made balance lever bearings from channel section brass (4mm x 4mm internal dimensions) with the outer face filed to resemble the etched fittings on the MSE sheet.  These are then soldered to mounting plates from brass strip, in turn soldered to the main post.  The false start was when I tried to be clever and make the bearing and mounting plate all in one piece, but this didn't allow any clearance for the pull wire to the innermost lever!

 

 

 

I've also made base plates for each post, including holes for fixing bolts and for the actuating rods which will emerge from underground.  The signal can now stand up!

 

 

I now need to prepare some ladders.  At the weekend I hope to pick up some nickel silver wire suitable for making the handrails, and hope for some decent weather next week so that I can get the paint aerosols out in the back yard!

 

 

 

 

 

[31A]

A few days of dry, if by no means sunny, weather here in York has allowed me to get out into the back yard with the Halfords Matt White Primer aerosol.

 

 

This may seem like a strange way to proceed, but I've decided to leave the platform handrails until last, so that I can get to the cranks to attach the operating wires without them getting in the way.  Eventually I intend to solder the handrail uprights into the holes drilled round the edge of the platform, and hope to be able to solder them into place from below.  Nevertheless I'm sure there will be touching up needed to the paintwork.  Similarly, I've given the decking a coat of Humbrol no. 64 matt light grey to start with, in the hope that I won't have to paint underneath the operating wires too much.  Eventually I'll weather the deck boards to make them look more like unpainted timber.  I've picked out the lamps, ladders and fittings using Tamiya acrylic flat black, which I hoped would run on more easily than the Humbrol enamel I would usually use but always seems to be the consistency of tar these days; it seemed to go on without too much bother, although painting the insides of the latticed posts was interesting!

 

[micknich2003]

Steve, looking good.

[31A]

Thanks Mick, just need to make it all work now!

[31A]

Just in case anybody was beginning to think I'd given up on this, an update.  Like many projects, the signal gantry seemed to take shape quickly to start with, but then the finishing off stages take an inordinate amount of time.

 

Since the signal arms have a 'dog clutch' device as part of the bearing, each arm is matched to it's bearing and so when painting them I had to make sure they remained identified as to their positions.  I had in mind that somebody had produced some transfers for signal arms at some time, but if so I can't find them now, so it was out with the Humbrol and the steadiest hand I could muster.  Transfers would make the job a lot easier!  The spectacles are glazed with the coloured film in the MSE range, fixed with Canopy Glue.  I'd earlier decided to model the Calling On arms with the red spectacles blanked off as usually seems to be the case; soldering a piece of brass strip behind the aperture also had the beneficial effect of strengthening the arms, which are quite fragile at this point.

 

 

The connections between the arms, cranks and weight bars are made using 5 amp fuse wire, being the thinnest wire I could find.  The wires only have to pull the arms 'off', as they drop back to danger under their own weight.  The first three arms have been installed and rigged up at this point.  These are connected to the three weight bars located on the inside of the post; the remains arms will go to the other group of three.  In the pictures the pull wires look rather 'unruly'; I'll tidy them up when I get nearer to finishing.  I was glad I'd decided to leave the handrails off until after I'd installed the arms and pull wires!  I've also left the finials off for now; these will probably be the last things to put on as they are quite vulnerable.

 

 

 

I've got a supply of 5 amp fuse wire but it did cross my mind that you might not be able to buy it very easily these days; a visit to my local hardware shop confirms that you can, but they don't seem to be so generous with the quantities these days!

 

 

 

 

 

[31A]

Progress has been intermittent recently; however I've now fitted all six arms, and connected them up to their weight bars.

 

Having done that, I made the railings and their stanchions from 0.45mm nickel silver wire which I thought might be stronger than brass.  I had to use a bigger soldering iron than I expected to solder the stanchions into their holes in the platform bearers - as these were made from 1.5mm square brass, they seemed to need a lot of heating up before the tinned n/s wire would solder itself to them.  The handrails have now been painted, but some touching up of the white paint remains to be done.

 

The finials also remain to be attached but I am saving this until almost last, as they are quite fragile and there will still be a need to handle the signal until I've finished making the underground operating mechanisms and finally got the signal in situ.

 

However, I have dug out foundations in the cork underlay and drilled holes for 6BA bolts to pass through the baseboard.  The right hand post has two bolts at its base and these will be screwed into tapped holes in the operating mechanism, while the left hand one just has one bolt which will pass through the baseboard into a nut.

 

 

 

 

 

 

[LNERGE]

Super stuff. It looks magnificent. It's just taken me two days to get a home and distant working. They are a bit bigger though.

[chris p bacon]

Looking good Steve.

 

On a related theme I was cataloguing some GNRS archive items today including Specifications, Bill of quanities and forms of tender for signalling between 1887 & 1918 in the Leeds area.

[31A]

Thanks, Dave.  That sounds interesting - any drawings among them?

[chris p bacon]

I need to go through them to record what the contents are, I'll let you know.

[31A]

This week I've been working on the underground 'mechanism' which will make the signal work.  It consists of six balance weights formed as 90 degree cranks, which work as 'pendulums' and will be connected by cords to the lever frame.  I don't claim any credit for this; it is based on the article by Chris Pendlenton in MRJ No. 12.  One deviation from his ideas though, is to make the pivots from 6 BA bolts, with the pivot holes in the cranks being tapped out this size, and the cranks then screwed onto the bolt.  The advantage of this is that the distance between the cranks is infinitely adjustable, and no spacers or retainers are need for the cranks.

 

The first picture  shows three of the six cranks attached to the piece of aluminium angle which forms the mounting bracket, with a further two cranks still separate.  The weights are strips of lead folded up and soldered to pieces of scrap rail, which also has a series of holes drilled into it for the eventual attachment of the cord.  The cranks themselves are cut from brass sheet, with a washer soldered over the pivot hole and a 6 BA tap through this hole.  The other ends of the cranks can be offset so that they lie as closely as possible to each other, without interfering with their neighbours.

 

 

 

The next picture, rather blurred I'm afraid, shows five of the six cranks mounted on the bracket.  Each group of three has its own pivot bolt; the bolt head visible here is the pivot for the cranks on the far side, and had to be set higher so that it can be screwed into the bracket after the nearer ones have been mounted.  Also visible is an 8 BA bolt which forms an "off" stop for the three cranks on the nearer side.  This is intended to prevent the working parts of the signal itself being stressed when the lever is pulled fully over.  There is no equivalent "on" stop as the "on" position is that at which the pendulums come to rest.

 

 

The third picture show the same thing in side view:

 

 

Lastly, a view of the attachments 'above ground', with five of the six weight bars having been connected to the underground cranks by 0.33mm brass wire.  I've done all this on a 'test rig' on the bench prior to installing the signal in its final position; this means I can make the necessary adjustments etc. to make it work without lying on my back under the layout too much, I hope!  before final installation the pull rods will be blackened to make them less obtrusive.  At this stage, I've left the long brass pin which forms the pivot for the weight bars 'long' in case I should need to get them out again for some reason, although I sincerely hope I won't have to!

 

 

 

 

 

 

 

 

[31A]

At this stage, I've left the long brass pin which forms the pivot for the weight bars 'long' in case I should need to get them out again for some reason, although I sincerely hope I won't have to!

 

 

 

 

Pride goeth before a fall - AAAARGHHHH!  In trying to connect up the links between the signal and the mechanism, I've managed to break one of the weight bars.  So I DID have to take out the pivot, and will have to make up a new weight bar.  Actually I realised it might be a weak point, as I'd laminated two weight bar etches together as far as the pivot, but left the ends (with the two outer holes) a single thickness to allow clearance in between the bars for the drives to be attached, as you can see in the picture in post no. 12.  They would be stronger if double thickness and I might try this with the replacement but I'm afraid I won't then be able to make it work ....

[LNERGE]

I bought some OO signal kits at the Stevage show and i'm finding them a bit fiddly and flimsy.. I can at least go out and install bits that are actually strong enough..

 

Edited March 4, 2017 by LNERGE

[uax6]

Slotted signal Richard? I can't quite make out but I guessing that the detector is on the slot bar?

 

Andy g