Great Southern Railway (Fictitious) - Signalling the changes...

[Skinnylinny]

I haven't, but I am familiar with working out the locking... the problem is I was about 80% of the way through working out the dog chart! Ah well, at least there's not *that* many changes to be made...

[makeitminiature]

Here's a link to the video mentioned by @Nick C.  There may be something of interest within it.

 

[Caley Jim]

Just out of curiosity, why green for the distant?  In my experience they were always yellow as they are in that video.  Was that an LBSCR practice?

 

Jim

Edited February 14 by Caley Jim

[Nick C]

10 hours ago, Caley Jim said:

Just out of curiosity, why green for the distant?  In my experience they were always yellow as they are in that video.  Was that an LBSCR practice?

 

Jim

My understanding is that distant levers changed from green to yellow around the same time that the arms changed from red to yellow - early 20s?

[Lacathedrale]

I just continue to be amazed by the Lever Frame system you've designed, @Skinnylinny - maybe because it just appears so user friendly.  I honestly can't believe this isn't more widely touted - it's truly revolutionary for those with FDM printers (or clubs which do) who want to get a nice lever frame without the aggro of the S4S kits.

 

I've worked out that it's £1.55 per lever versus the £8/lever of the S4S frame. For a layout like Brighton Trafalgar, which requires about 30 levers- that represents a cost differential of about £200.  The rub of course is that the S4S frame is well proven, metal rather than resin, and has direct microswitch compatibility.

 

From my own personal perspective I reckon before printing the remaining components and buying the metal parts, I feel like I need to design or see some kind of actuation of the levers against microswitches - presumably some kind of forked push-rod attached to the bottom of the lever, passing through a guide to depress the microswitch? Is this something you might consider before diving straight into the interlocking?

 

 

Edited February 15 by Lacathedrale

[Skinnylinny]

There's still a few bits I need to work on with the levers - as you've probably either found (or will do!) the printed catch rod guides aren't *super* strong, and can be broken off if a lever is tugged against the catch. I may look at getting some of the parts CNC machined in metal. For now, and for testing the interlocking, they suit nicely!

The system I have in mind for the actuation will likely not get designed properly until after Model Rail Scotland in Glasgow later this month, as I've got a lot of things on my plate until then, I'm afraid. The lever frame is still very much under development.

[Lacathedrale]

Yeah, I feel like the chubby kid who has grabbed all the sweeties out of the jar and is now indignant that there aren't any more! I'll sit on my hands for the moment, as I have enough parts for a working prototype and my layout's just about to approach basic operational function and I want to have a play with it for a bit first before embarking on the next major project. Cheers!

 

ps. may I ask where/how to drew up your signalbox diagram? It's gorgeous!

Edited February 15 by Lacathedrale

[Skinnylinny]

Thank you! I drew it up in Microsoft Paint, using various photos of Saxby & Farmer diagrams as inspiration. The idea is to eventually trace it and do it "properly" with waterproof black ink and watercolours... 



Source: https://www.gwra.co.uk/auctions/gnr-signal-box-diagram-humberstone-station-diagram-2017nov-0045.html

Edited February 15 by Skinnylinny

[Compound2632]

3 hours ago, Nick C said:

My understanding is that distant levers changed from green to yellow around the same time that the arms changed from red to yellow - early 20s?

 

For the Midland, Midland Style gives:

• distant signals - olive green
• stop signals, ground signals, and discs - red
• points - Oxford blue
• ground frame controls - yellow
• level crossings and wicket gates - brown
• spares - white

Unfortunately, LNWR Liveries and North Eastern Record are only concerned with the outsides of signal boxes. But it seems to me probable that lever colours would have been agreed on nationally, presumably through one of the RCH committees.

[Nick C]

10 minutes ago, Compound2632 said:

 

For the Midland, Midland Style gives:

• distant signals - olive green
• stop signals, ground signals, and discs - red
• points - Oxford blue
• ground frame controls - yellow
• level crossings and wicket gates - brown
• spares - white

Unfortunately, LNWR Liveries and North Eastern Record are only concerned with the outsides of signal boxes. But it seems to me probable that lever colours would have been agreed on nationally, presumably through one of the RCH committees.

Not black for point levers? I'd assumed that was pretty universal. Release levers were blue over brown later on...

 

It does seem logical that colours would be standardised, though I guess not essential as signalmen from one company wouldn't generally operate a box from another? 

[Lacathedrale]

Excellent, that's a lot of patience, right there!

 

Reviewing the S4 Society frame, it looks like they mount microswitches against the long end of the lever arm, while the bottom of the lever is as you have described for connection to an interlocking system.

 

 

Maybe this could be facilitated with exterior end plates through which run the 2.5mm rods for the microswitch to mount to?

 

I've whipped something up in Fusion360:

 

The idea being it could be fitted non-destructively as a girdle to any existing lever frame of your design to provide an interim microswitch solution while interlocking/etc. was worked on. I'd be happy to continue this if you are at all interested, though I imagine your solution would be far more elegant!

 

More along your specific point about fragility - I wonder if the addition of a brass plate infront of the catch-rod guides and atop the frame rails might be a simple expedient for stability? I would've thought the hooks for the springs would be the most fragile aspect.

Edited February 15 by Lacathedrale

[Skinnylinny]

The hooks for the catch rods have so far not been too fragile, as they are only ever acted on by fairly weak springs. The difficulty is been having with the catch rod guides on the levers is that the 3d printer layers can, if the lever is pulled on without operating the catch handle, delaminate causing the end to snap off. A possible solution would be to carefully solvent weld another printed strip over the open side once the catch rod is inserted. This does trap the catch rod permanently though. The printed strip would be printed with the layer lines oriented differently in order to give added strength. 

 

I like the idea of the microswitches on a "girdle" - if I'd known you were going to attempt to edit the files in Fusion I'd have sent you the Fusion files as well as STLs! 

 

My only thought with mounting microswitches like that is that there may be a fair amount of flex in the 2.5mm rods over their length, which might result in unreliable positioning. Perhaps inserting similar mounting holes every few quadrants might help with that. I'll have a look, thank you! 

[Lacathedrale]

The F360 files might make things simpler, but in no way do I wish to take away any of your thunder on this one!

 

The S4 lever frames have closed ends every five levers into which there are tube bearings for the microswitch mounting rod, which presumably limits the flex to something reasonable. While thinking about how to provide intermediate support, I reckon I've imagined a better solution overall: a clamp-type attachment onto the rear leg of the frames which is held in place with nuts/bolts, providing a pill-shaped boss with the two bearing holes for the rod to register through.

 

I imagine a pair of 2mm mounting holes in the rear leg would make things easier, (or indeed simply adding the bosses to the frames) but it would then be compromising the original and prototypical design.

 

[ianathompson]

On 15/02/2024 at 13:05, Nick C said:

Not black for point levers? I'd assumed that was pretty universal.

 

The Midland, I believe, used economical FPLs which operated the lock and blades simultaneously.

There were no FPL levers as such, hence the blue colour.

The "standard" arrnagement which I worked with in manual GER boxes was black for point blades and blue for FPL.

The GER practice was for the FPL lever to be out of the frame when the points were locked.

On some other railways I understand that the FPL lever was in the frame when providing the locking.

 

Confidently waiting to be contradicted and put right!

 

Ian T

Edited February 16 by ianathompson
typo

[Compound2632]

37 minutes ago, ianathompson said:

The Midland, I believe, used economical FPLs which operated the lock and blades simultaneously.

There were no FPL levers as such, hence the blue colour.

 

Ah, but, it appears that all point levers were blue, irrespective of whether facing or trailing - i.e. with or without FPLs, economical or otherwise. There were very many Midland boxes controlling layouts with no facing points.

[Nick C]

21 minutes ago, ianathompson said:

The "standard" arrnagement which I worked with in manula GER boxes was black for point blades and blue for FPL.

The GER practice was for the FPL lever to be out of the frame when the points were locked.

On some other railways I underdtand that the FPL lever was in the frme when providing the locking.

That certainly matches the LSWR practice that I'm more familiar with.

 

Brighton practice seems a bit more varied when it comes to FPLs - Looking through the Pryer book on West Sussex lines I see 8 stand normally in, 5 normally out, and 7 don't say.

[ianathompson]

43 minutes ago, Compound2632 said:

Ah, but, it appears that all point levers were blue, irrespective of whether facing or trailing - i.e. with or without FPLs, economical or otherwise. There were very many Midland boxes controlling layouts with no facing points.

 You are probably correct with the Midland.

I had momentarily forgotten their aversion to facing points.

I believe that  I once read somewhere that there was only one between Settle and Carlisle!

Presumably at Hellifield?

 

Ian T

[Compound2632]

1 hour ago, ianathompson said:

 You are probably correct with the Midland.

I had momentarily forgotten their aversion to facing points.

I believe that  I once read somewhere that there was only one between Settle and Carlisle!

Presumably at Hellifield?

 

Ian T

 

At Appleby, where there was a double junction connection to the NER.

 

Hellifield south of Settle!

[Edwardian]

On 16/02/2024 at 19:24, Compound2632 said:

 

At Appleby, where there was a double junction connection to the NER.

 

 

 

Do you know when?

 

According to the 1897 OS survey (if  accurate) it appears to be single, but double by the time of the 1911 revision.

[Compound2632]

1 hour ago, Edwardian said:

Do you know when?

 

According to the 1897 OS survey (if  accurate) it appears to be single, but double by the time of the 1911 revision.

 

I have to say my reading of that 1897 survey:

https://maps.nls.uk/view/125822844

is a double junction.

 

According to V.R. Anderson and G.K. Fox, Stations and Structures of the Settle & Carlisle Railway (OPC, 1986), Appleby North Junction signal box was brought into use in 1890, along with Appleby (station), New Biggin, etc. so it looks as if there was a general re-signalling of this section of the line in 1889/90.

Edited February 20 by Compound2632

[Skinnylinny]

Whew. It's been nearly a week since Model Rail Scotland, and life is nearly back to normal. Unfortunately, I rather over-exerted myself the first two days, and the chronic fatigue syndrome reared its ugly head, with 'flu-like symptoms, on the Friday evening. Indeed, the glands in my throat were so swollen and sore that I could barely swallow. However, lashings of ginger-and-honey tea and the Good painkillers, and 25 hours' sleep between Friday evening and Sunday morning meant that I was feeling well enough to make it back for the last day, even if I did have to take things easy.

It was wonderful to meet with friend old and new, including @Caley Jim (who brought one of his 2mm FS scratchbuilt Caledonian vans to compare with the Rapido 3D-printed prototypes), and meeting @Citadel for the first time. 

 

 

Forgive the broken door rail - those parts on the real wagon will be etched, and are exceptionally thin to print!

 

The shopping list was very short this year - I picked up a bogie caboose kit for the American HO stock (well, at £3, it would have been rude not to - it even had pre-formed grab rails!), several sets of wheels for forthcoming wagon projects, and a £6 Cooper Craft GWR V1/V5 cattle wagon kit, to be painted blue-grey and run with the Titfield buffet car and Toad. Now, all I need is a 14xx...

 

I've also done a successful print of some parts for the lever frame interlocking. This was a test piece, keeping the distant lever (lever 1, to the right in the photo) locked at "normal" or "caution" unless levers 2 and 3 are reversed (clear)). Yes, I know that lever 3 is a points lever here, this bit was a proof of concept!

 

 

Now printing is a slightly larger locking tray, and another type of locking; this time, a facing point lock, such that when lever 4 is reversed, it locks lever 3 in whichever position it's in at the time. Mighty oaks from little acorns grow, and all that!

[Michael Hodgson]

On 15/02/2024 at 13:05, Nick C said:

Not black for point levers? I'd assumed that was pretty universal. Release levers were blue over brown later on...

 

It does seem logical that colours would be standardised, though I guess not essential as signalmen from one company wouldn't generally operate a box from another? 

 

With regard to lever colours, they were not completely standardised between companies, although there was a lot of similarity.  It was relatively unusual for a signalman to move from one company to another, I suspect he would have to start again at the lowest grade.

 

Most of the inconsistencies affected the slightly more obscure functions, such as releases for ground frames, locks on gates, turntables or swing bridges; gongs; fog apparatus; King levers (used for re-arranging the locking when switching a box out of circuit at night).

There have also been changes over time, partly because of the need to standardise as companies got absorbed into larger groups.

 

The best known change was for distant levers, green until mid 1920s, yellow afterwards - except of course in Ireland which had been following British practice but had by then become independent, so they remain green to this day in the Emerald Isle. 

 

Current practice can be found here https://modratec.com/mud_lev01.php

 

Historic GWR and NER schemes here

https://old.signalbox.org/frames/gwcolours.htm

https://old.signalbox.org/frames/nercolours.htm

 

 

 

[Michael Hodgson]

1 hour ago, Skinnylinny said:

Whew. It's been nearly a week since Model Rail Scotland, and life is nearly back to normal. Unfortunately, I rather over-exerted myself the first two days, and the chronic fatigue syndrome reared its ugly head, with 'flu-like symptoms, on the Friday evening. Indeed, the glands in my throat were so swollen and sore that I could barely swallow. However, lashings of ginger-and-honey tea and the Good painkillers, and 25 hours' sleep between Friday evening and Sunday morning meant that I was feeling well enough to make it back for the last day, even if I did have to take things easy.

It was wonderful to meet with friend old and new, including @Caley Jim (who brought one of his 2mm FS scratchbuilt Caledonian vans to compare with the Rapido 3D-printed prototypes), and meeting @Citadel for the first time. 

 

 

Forgive the broken door rail - those parts on the real wagon will be etched, and are exceptionally thin to print!

 

The shopping list was very short this year - I picked up a bogie caboose kit for the American HO stock (well, at £3, it would have been rude not to - it even had pre-formed grab rails!), several sets of wheels for forthcoming wagon projects, and a £6 Cooper Craft GWR V1/V5 cattle wagon kit, to be painted blue-grey and run with the Titfield buffet car and Toad. Now, all I need is a 14xx...

 

I've also done a successful print of some parts for the lever frame interlocking. This was a test piece, keeping the distant lever (lever 1, to the right in the photo) locked at "normal" or "caution" unless levers 2 and 3 are reversed (clear)). Yes, I know that lever 3 is a points lever here, this bit was a proof of concept!

 

 

Now printing is a slightly larger locking tray, and another type of locking; this time, a facing point lock, such that when lever 4 is reversed, it locks lever 3 in whichever position it's in at the time. Mighty oaks from little acorns grow, and all that!

 

This approach looks good, but I wonder whether you will have trouble over time.  Even the steel locking of the prototype suffered from wear and frames sometimes needed to be replaced after heavy usage (though less commonly than because of changes in layout to meet new traffic requirements). 

 

Model usage is generally a lot less than the prototype of course, and if your tappets and locking bars are drawn up individually in CAD and the files kept, I suppose it should be a simple matter to run off replacements to deal with wear.  Just as some designs of locking frame on the prototype were notably more robust and hard-wearing than others, of material will have quite an impact on how long a model lasts. 

[ianathompson]

On 01/03/2024 at 16:19, Michael Hodgson said:

This approach looks good, but I wonder whether you will have trouble over time.  Even the steel locking of the prototype suffered from wear and frames sometimes needed to be replaced after heavy usage (though less commonly than because of changes in layout to meet new traffic requirements).

 

The locking fitters used to come around every few years to dismantle the locking trays for cleaning and maintenance.

They worked sequentially down the branch, ignoring our electrically locked panel.

As a relief I usually caught all three boxes with massive holes in the floor and no locking etc.

It became a standing joke with the fitters because the "residents" booked the week off when the word got out!

I used to enjoy working in "degraded conditions" and it certainly helped when something went wrong for real.

 

As an aside I was the only signalman to gain their respect for manually dismantling a frame by pulling a lever too hard!

That was in the box shown on the icon.

Something had gone wrong with the lock which was "a bit stiff."

I got the lever out eventually but bent the ironwork at the back of the frame.

Nothing that brute force and ignorance cannot deal with!

 

Ian T

Edited March 2 by ianathompson
additional info

[Skinnylinny]

I do expect the parts to wear over time, so yes, I've been building the whole interlocking setup in CAD such that any one part can be re-printed if worn. I hope that the forces involved should be rather less that that inflicted on a full-sized lever frame, too! 

If money were no object, I would love to get the interlocking (and the levers) CNC-machined from metal, but I'm running on a relatively tight budget. At least with the 3D printing, it's easy to change things when I inevitably make silly mistakes. For example, the first time I printed a locking bar, I had managed to design the locking "dog" such that it locked both levers and neither could move! Fortunately, 20 minutes later I had a new one, and all worked smoothly.

Lever 1 (distant) is locked normal unless the home (2) is reversed, and reversing lever 4 (FPL) locks lever 3 in either position. Incidentally, in this photo you can see the surface finish that "ironing" has on flat horizontal surfaces. They certainly slide over each other much better!

 

I've decided that I will number the tappets when printing them, in order to make assembly easier, as can be seen on tappets 3 and 4 above. Now, I need to finish the locking table before I can get much further...