Verwood, Dorset - 3D Printed LSWR Type 1 Signal Box

[Blandford1969]

6 hours ago, Steve Smith said:

After an 'interesting' tussle with OpenSCAD since it doesn't allow the user to set variables in conventional 'if' statements, but does allow one to do it in a weird conditional assignment with 'C' language like syntax, the computing gods were smiling again.

And to please our Christopher, this is West Moors masquerading as an Evans O'Donnell frame with black numbers on white or yellow plates - still just in boring old grey resin.  As with the Verwood Crane, these could be printed much more impressively in 7mm scale.

 

Peter Russell cannot remember what the frame was, as he says he just enjoyed being able to pull the occasional lever , could I also get a stove as well please?

[Steve Smith]

There was always a question mark in my mind about the angle on the pulled lever.  Looking at photos of Stevens' style frames, it dawned on me that my lever slots came too close to the front.  Reducing the angle from 27° to 25° moved the end of the slot back by the right sort of amount and I think improves the look. 

 

This is the Verwood Frame ready to receive a train from Salisbury.  Interestingly, the locking diagram indicates that lever 2 locks lever 5 and 8, whilst lever 5 locks lever 2.  I'm sure Chris will be along in a little while to put me right.   This render adopts a more subtle blue that is closer to the lever colours on the MHR.

This is the partially assembled set of STL files, without the sashes, and therefore ready for printing.   I have a size for the Styrene floor which I have simulated, and have positioned the lever frame and stove.   The lever frame will need to sit in a hole in the floor with some closing boards around it and a tread board in front - a bit like the real thing.  I am fairly confident about the size of the stove, but it looked too large in the builder's opening of the wall.  Referring back to Nick C's MHR photos, it was clear that my fireplace was a tad undersized, and this render has the enlarged item.   There were two short section tablets, plus the long section token, so I'm thinking three machines.  It looks like there were two on the left, but there is no photo showing the right side of the frame and any instrument that might be there.

 

Of things left to do, there's no door - that I'll etch with the window sashes in multiple layers to take the glazing in a pocket, probably with the options of the half glazed four panel Verwood door, plus a half glazed four pane door that seems popular on the MHR.  I shall probably also model the distinctive cupboard in the rear corner, and I'm thinking that the interesting mountain of tablet/token instruments to the left of the frame is worth doing too.

 

[LNERGE]

One of my boxes at home has a Stevens frame if you need pictures or measurements. 

[RailWest]

>>>Interestingly, the locking diagram indicates that lever 2 locks lever 5 and 8, whilst lever 5 locks lever 2...

 

Quite true. Homes for opposing directions lock each other to ensure that only one train can enter at a time. Lever 2 can NOT be pulled if 5 is reverse.

 

4 and 5 would be reverse ONLY for when the box was switched out. When the box is 'in' to accept a train from Fordingbridge, and assuming that it would be passing an Up train, would require 2 on, normal, Down loop clear to 3, 5 normal and 4 reverse to lock 5. 2 should be pulled off only when the approaching train is (nearly) at a stand at 2 (i/a/w Rule 39a). 

Edited July 18, 2022 by RailWest

[RailWest]

>>>There were two short section tablets, plus the long section token, so I'm thinking three machines.......

 

No :-)

 

As Verwood was not a block/tablet post for the 'long section' it would not have a long section METS instrument, those would exist only at Fordingbridge and West Moors. There was of course the 'switch mechanism' on the floor at the RH end which held a METS when Verwood was 'in' or two x tablets when it was 'out'.

 

It was common for ETT/ETS/EKT machines to put one each at their respective ends of the box, but it was not unknown to have them together at one end or the other. I suspect it all depended upon available space (not much in an early Type 1 box!) and (sometimes) how the boxes were extended to hold the ETT machines when upgrading from TS&T working.

[Steve Smith]

3 minutes ago, RailWest said:

 There was of course the 'switch mechanism' on the floor at the RH end which held a METS when Verwood was 'in' or two x tablets when it was 'out'.

Excellent, I have a photo showing that little device, and now I know what it was there for!  :-)

3 minutes ago, RailWest said:

 

It was common for ETT/ETS/EKT machines to put one each at their respective ends of the box, but it was not unknown to have them together at one end or the other. I suspect it all depended upon available space (not much in an early Type 1 box!) and (sometimes) how the boxes were extended to hold the ETT machines when upgrading from TS&T working.

To the uninitiated (that's me), it looks like there were two tablet devices at the left-hand end, but they do look different.  Do you happen to know what they would have been?  I was going to start by tackling the varnished hardwood cabinet they stood, and take it from there.

To continue to wile away the time while my sciatica clears up, I tackled the cupboard in the corner.  I have a head on photo showing the right-hand door and a bit of the left-hand door, plus a couple of supporting shots showing less of the same end, one of them showing that the register was kept on it.   I had formed the idea that the left-hand end could only be a half cupboard, but when I mocked it all up and checked the proportions it seems that there was room for two identical doors, both left hand hinged.  Compared with the MHR boxes, this seems  a generous allocation of cupboard space.   As on the prototype, the doors don't fit ever so well, and the right-hand one is ever so slightly ajar, as in one of my photos.  I reckon there would have been a chair for the bobby between the fireplace and cupboard.

[RailWest]

>>> it looks like there were two tablet devices at the left-hand end, but they do look different....

 

Hmm.... given that both 'short' sections were worked by Tyer's No 6 ETT instruments, they ought to look the same. What have you got by way of photos  to suggest otherwise ????

 

I am familiar with the image of the LH end of the frame, where the machine for F/bridge can be seen quite clearly. The one for W/Moors ought to be similar.....

Edited July 18, 2022 by RailWest

[Nick C]

2 minutes ago, Steve Smith said:

Excellent, I have a photo showing that little device, and now I know what it was there for!  :-)

To the uninitiated (that's me), it looks like there were two tablet devices at the left-hand end, but they do look different.  Do you happen to know what they would have been?  I was going to start by tackling the varnished hardwood cabinet they stood, and take it from there.

To continue to wile away the time while my sciatica clears up, I tackled the cupboard in the corner.  I have a head on photo showing the right-hand door and a bit of the left-hand door, plus a couple of supporting shots showing less of the same end, one of them showing that the register was kept on it.   I had formed the idea that the left-hand end could only be a half cupboard, but when I mocked it all up and checked the proportions it seems that there was room for two identical doors, both left hand hinged.  Compared with the MHR boxes, this seems  a generous allocation of cupboard space.   As on the prototype, the doors don't fit ever so well, and the right-hand one is ever so slightly ajar, as in one of my photos.  I reckon there would have been a chair for the bobby between the fireplace and cupboard.

Alresford box has two cupboards - the one under the register desk is used for "domestic" stuff (tins of brasso, bin bags, etc), while the lower one by the door is for dirtier stuff (clips and plugs etc). The ones in Alton (which I believe was acquired as an empty shell) are standard kitchen type cabinets - a suitable style door and a coat of BR green and the difference isn't that obvious!

 

Remember though, in those days there would have been a locker for each regular signalman to keep their stuff in, which we don't have. 

[Steve Smith]

7 hours ago, LNERGE said:

One of my boxes at home has a Stevens frame if you need pictures or measurements. 

That would be very kind of you!   The distance between the centres of the bolt heads at the end would be a useful sense check for the scale of my 3D model.   Then perhaps the length of the slots and their distance from the toe for the throws.   The only drawing of a Stevens frame that I could find was of the Scottish variant, and does look different to the London version.

 

Although late in the design process, I can make changes until the STL files go off to the printer.

[Steve Smith]

16 minutes ago, RailWest said:

>>> it looks like there were two tablet devices at the left-hand end, but they do look different....

 

Hmm.... given that both 'short' sections were worked by Tyer's No 6 ETT instruments, they ought to look the same. What have you got by way of photos ????

I can now see that what I took to be two token instruments, is just the one Tyers No.6 instrument - so perhaps the other one was at the right hand end?   Have sent you a PM with the photo and will now look through all my other photos again.

[RailWest]

13 minutes ago, Steve Smith said:

I can now see that what I took to be two token instruments, is just the one Tyers No.6 instrument - so perhaps the other one was at the right hand end?   Have sent you a PM with the photo and will now look through all my other photos again.

That's got rid of that red-herring then :-)

 

Have a look at pix of the front or door end and see if you can spot the 'tombstone' shape thru' the windows at the W/Moors end.....

[Steve Smith]

Not too far from the Verwood signal box and spending the winter deep under the canopy and the summer in front of the Waiting Room was this distinctive station seat. 

Similar to the ones found on the Salisbury & Yeovil (S&Y) but with a much more relaxed back rest.  The photos I have are not terribly clear, but there is more than a hint of the curved seat as per the S&Y, but the feet were joined unlike the S&Y seats (as at Semley).  Same, but definitely different!  

Edited July 19, 2022 by Steve Smith
Add photo!

[LNERGE]

On 18/07/2022 at 16:45, Steve Smith said:

That would be very kind of you!   The distance between the centres of the bolt heads at the end would be a useful sense check for the scale of my 3D model.   Then perhaps the length of the slots and their distance from the toe for the throws.   The only drawing of a Stevens frame that I could find was of the Scottish variant, and does look different to the London version.

 

Although late in the design process, I can make changes until the STL files go off to the printer.

Sorry just seen this. Out installing a point machine tomorrow. I’ll sort it Friday. 

[Steve Smith]

Luckily I have a couple of photos of the instrument shelf, and with a lot of help from Chris we have been able to arrive at an educated guess as to what was there - needless to say it's him wot's educated not me, and the mistakes needless to say are all mine!

This is configurable with length based on the number of levers, but only the repeaters line up with the relevant lever.   The script that creates it has a line for each item and specifies the position of the item on the shelf in relation to the lever numbers including between levers as the 'position' doesn't need to be a whole number, plus if necessary the colour of the item or its size.    The shunting and block bells are more randomly placed, with a block gong for Fordingbridge at one end, a block bell for West Moors at the other end, and in the middle what we have assumed to be a shunting bell, possibly to communicate with the Ground Frame.  The drum rendered black is likely to be a relay of unknown purpose.   The repeater for the down home bracket signal was dual aspect, so just the one binnacle needed for that.    I have to remind myself that all this is just 18mm long in 4mm scale, and not to get carried away - the stalks for the bells are just 0.3mm diameter!   It's a very good match for the photos, and that's all I can ask.

 

I need to measure a couple of Tyers No.6 ETT machines (Shillingstone and MSN both have at least one), and then the signal box render will start to look quite crowded.

 

 

[Steve Smith]

 

 

Verwood also had a Ground Frame.  It was housed in a corrugated tin shed that was almost certainly unique to Verwood.  Colour photos show it to have had a greenish hue, which would be an option if it was considered to be in the station environs and hadn't already been given a coat of bitumen.  It was off the end of the down platform, and every down train would have required a visit to the hut to work the points at the West Moors end.  I actually suspect two visits, as the bobby would need to reset everything after tablets had been exchanged, and the train had been signalled out of the loop from the box. 

This was built the old-fashioned way a couple of years ago.   Slaters styrene sheet was used, and the corrugations are a tad over scale in 4mm scale, a deficiency shared with the lamp hut, weighbridge hut and canopy roof.   The door of the hut was open in all the photos that I have, so I modelled the framing on the inside, and what it's crying out for is a Ground Frame. 

We don't know exactly which type it had, but Midsomer Norton had some RSC frames that the friendly and helpful S&T people let me measure and photograph last year.   This is the result - the start of another tiny sciatica project! 

[RailWest]

On 02/07/2022 at 13:30, RailWest said:

West Moors in BR days had the SR style of plates (painted ovals), /probably/ a replacement set done i/c/w the war-time alterations, but one would need to check the SR's order books to confirm that.

Well now, it would appear that a complete new set of plates matching the WWII arrangements were ordered on 4th June 1940, so given the 1943 opening date of the new WD sidings, then the work much have been in planning for some while. Interestingly all 23 levers were in use, No 23 being - rather as I suspected - used for the Gate Stops, so I wonder when and why they dispensed with that?

[RailWest]

11 hours ago, Steve Smith said:

 

 

Verwood also had a Ground Frame.  It was housed in a corrugated tin shed that was almost certainly unique to Verwood.  Colour photos show it to have had a greenish hue, which would be an option if it was considered to be in the station environs and hadn't already been given a coat of bitumen.  It was off the end of the down platform, and every down train would have required a visit to the hut to work the points at the West Moors end.  I actually suspect two visits, as the bobby would need to reset everything after tablets had been exchanged, and the train had been signalled out of the loop from the box. 

This was built the old-fashioned way a couple of years ago.   Slaters styrene sheet was used, and the corrugations are a tad over scale in 4mm scale, a deficiency shared with the lamp hut, weighbridge hut and canopy roof.   The door of the hut was open in all the photos that I have, so I modelled the framing on the inside, and what it's crying out for is a Ground Frame. 

We don't know exactly which type it had, but Midsomer Norton had some RSC frames that the friendly and helpful S&T people let me measure and photograph last year.   This is the result - the start of another tiny sciatica project! 

Allowing for a mass of assumptions....:-)

 

Given that the basic layout at Verwood seems to have been original, then a GF would probably have been provided at the same time as the SB. As we know from photo evidence that the frame in the SB bore the Stevens & Son name, probably the GF was the same. It was only in later years, after the Stevens patent lapsed, that the L&SWR bought frames from other contractors and I would guess that Verwood had one long before 1898. Of course, there is always the chance that the original GF had to be replaced for some reason...

[Blandford1969]

Going slightly off topic again, does this photo of the West Moors frame taken from the Crossing Wheel end help with identifying the frame. I'm amazed by the block detail 

 

(I have sought permission to post this - it is in a non commercial form and comes from the Castleman's Corkscrew by the late Brian Jackson, a two volume series on this history of the line)  

Best wishes

Duncan

[RailWest]

>>>does this photo of the West Moors frame taken from the Crossing Wheel end help with identifying the frame.....

Only to confirm what was known already, namely that it was of the Stevens & Sons pattern. We would need to see the end-plate just above the floor to read the actual maker's name.

 

[Steve Smith]

After much chipping away at virtual resin, the ground frame has re-emerged as a Stevens & Son product and has sprouted levers, descriptor and pull plates and a front cover.   I doubt if the rear was boxed in, especially since it was in a hut, so I'm contemplating whether some slightly thickened 'rails' should be allowed to poke out the back.  I've left the RSL style 'teeth' where the interlocking 'racks' must have mounted for now.   An RSL version is still an option, as are Southern oval descriptor plates.

Verwood needs a couple of Tyer's No.6 Tablet instruments, and West Moors needs one too, so with Chris' measurements from Midsomer Norton, the last couple of days have been spent on this rather garish monster.

 

Looking more like something from a fairground, the base unit is probably unique to Verwood with the hint in my reference photo that the front had a door, and that this was another cupboard.   Not having any clear photos of the brass pull handles on the sides - something similar was traced off the interweb.  Some sort of transfer will be needed for the front of the tombstone.

Most satisfyingly of all, a mock-up of the signal box interior with instrument panel and tablet instruments.  It seems likely to me that the West Moors instrument would have been in the corner to enable access to the long section token device (not shown), and to behind the frame to the adjustors for the signal wires.   In this position, it would not have appeared in any of my photos of the interior.  The toe of the lever frame is now correctly in line with the cupboard and the frame slightly enlarged in line with Chris' measurements at MSN.

Edited July 28, 2022 by Steve Smith

[Steve Smith]

A cupboard door has been added, this was partly informed by hints in the murkiness of a Verwood photo, and what could be seen in the Midford box on that other S&D.   The framing widths have been refined to be more in line with Midford, which can be seen much more clearly than the Verwood unit.   The brass handles on the side panels has been traced from a photo of the real thing also kindly provided by Chris.  That handle is about 1mm long in 4mm scale, so just an impression required!  That photo also showed that the chamfer stops were curved, and due to the way I had implemented them originally this was very easy to replicate in the model.  The lever has been added to the left-hand side, together with what looked like a knurled fastener on the side of the tombstone.  With that, I think it's ready for a test print.   For completeness, I would very much like to do the floor mounted METS unit for the long section, but have a low resolution photo and no other information to go on.

[RailWest]

Yes, there was a knurled knob on each side of the wooden 'tombstone' cover...

 

...but no, I've not counted the number of notches in the 'knurl' !! :-)

[Nick C]

Here's the end plate of the Alresford frame - Dutton & Co. Not sure how visible it is in the photo, I'm writing this on my phone...

 

[Steve Smith]

 

One of the mysteries at Verwood was the light grey cabinet behind the signal box.  This was probably installed in the 1930s to hold batteries used in conjunction with the electric locks of the new switching out mechanism.   This cabinet is visible in an Eyers picture of the station frontage, but it on its own this was insufficient for modelling purposes.  Luckily, the photo that proved I had the signal box chimney wrong, showed the top of the cabinet and enough of the front, to produce the renders above.   Over the gaps between the pairs of doors there appears to have been some very heavy cover strip, and the Eyers photo has some strange diagonal artefacts across it that are impossible to interpret.  There should probably be a padlock, or other means of securing the doors, and suggestions would be welcome.   It's not won me over yet, and is still a work in progress.

 

Edited August 7, 2022 by Steve Smith
Upload render with revised chimney detail.

[Steve Smith]

To some extent because I can, and because I have a soft spot for the neglected signal box at Downton, I have started the process of creating a full height version of a Type 1 signal box.   Based around Verwood it uses details from the box at Fordingbridge (locking room access and light), but will use Downton as inspiration for the steps and porch. 

It has also gained the finials that could be seen at Downton almost to the end, that will look great on any Victorian version of the box, as I suspect they all had them originally.  They are a strange shape, but at Downton at least they really did look like that!  A full set of test prints for the Verwood specific box are winging their way to me, including a very nice looking roof that was printed in one shot, something I really didn't think would be possible.