St Albans South Signal Box

You forgot to tell us when the next open day is John...

QUOTE (Bear 1923 @ 21 Feb 2018, 10:27) <{POST_SNAPBACK}> You forgot to tell us when the next open day is John...
See post #159 above - it's the 11th March!

When's the next?

QUOTE (Bear 1923 @ 10 Apr 2018, 00:06) <{POST_SNAPBACK}> When's the next?
April 22nd, 2-5pm. See www.sigbox.co.uk for a list of forthcoming open dates, and the News 2018 page for recent photos.

Regards,
John

Hooray! Just found out I can directly link images from the Signal Box's own website, so here's a selection to illustrate recent developments.

The expanded garden railway, now double-tracked:

But no trains in mid-March:

And our passengers were rather chilly as well:

But seem to have suffered no harm when seen in the sun a few days later:


I'd mentioned above our recently acquired 'station lights' - here's a few shots of them.
As received - photo rotated so we could see what they would look like when mounted:

Under restoration:

First one mounted:

and working:


Our 20,000th visitor and his family:


Behind them is our new 'flower bed' sign:

Made from concrete letters - cast in stout cardboard moulds - and placed on a background of small white chippings.

John

June saw a steady round of work and also attendance at the Herts Steam Show held in St Albans in blazing sunshine - the start of the heat-wave, although we didn't know it at the time!

July saw quite a lot of things going on. We had been given two 'carriage lights' which we decided to fit in our toilet instead of the rather bland fluorescent fitting put in when the box was restored ten years ago:

The toilet is without windows, so we added an emergency light fitting which we hadn't thought to ask for when planning the restoration.

More signal bits and pieces have arrived - one of our newer members is a recent retiree from Network Rail and has a wide range of contacts - fortunately for us!
A flood-lit SR Ground Disc from the Petersfield area:

Note too the 'point detector' in the foreground - this we hope to include in a new demonstration - see next but one picture below!

A rear view showing how this was a conversion from a shut signal with an arm - Westinghouse 1942 according to the main body casting:


Again through the same member who got us the above signal, the Talyllyn Railway offered us a set of stock rails and point blades so we can construct a demonstration point to be worked by one of our ground frames. Here are the said rails which were brought down by two of our members yesterday:

Seen here temporarily laid out on site - a lot of work awaits us to prepare a suitable area on which we can set up the point - probably to a narrower gauge than the Talyllyn's 2ft 3in.

John

QUOTE (John Webb @ 2 Aug 2018, 13:20) <{POST_SNAPBACK}>A rear view showing how this was a conversion from a shut signal with an arm - Westinghouse 1942 according to the main body casting:


John

Good to see your progress
Looking at the back of your "dummy" we can see the heavy cast metal "body" arm below the aspect holes and partly hidden by the top of the leg - which forms the flat floor that the original casing for the oil lamp would have sat on in the middle of the structure. To the right of the floor is the lamp bracket that held the lamp casing in place. The spindle passes through just below the floor and at the back of the signal is attached to the blinder - the kidney shaped lump of metal on the bar from the back end of the spindle. The disc of the signal is a standard SR "half moon" designed to be well clear of any adjacent live rails. (For reasons not known to me the GWR also used half moon discs on some shunt signals). Discs replaced small straight arms quite soon after the introduction of semaphore shunt signals. The straight arms were only the depth of the heavy metal arm but the same length as the width of the disc. They were red or yellow with a vertical white or black stripe near the left hand end - so miniature versions of full sized signals.

Usual request... Next open days/special days?

B)

Next Open Afternoons 2-5pm: August 12 and 26th. Extended opening 10am-5pm for Heritage Open Days Sat 8th and Sun 9th September. The latter will be celebrating the 150th anniversary of the opening of the line from Bedford through St Albans to St Pancras and Moorgate.

See http://www.sigbox.co.uk for location information etc.

Sorry for the "shut signal"! By the time I noticed the spelling error I was timed-out from editing it! I also meant to mention that this differed from the usual White and Red shunt signals. It could be passed at the 'Caution' position (as shown in the photograph) as far as the line was clear. Frequently used in head-shunts to allow shunting to take place without involving the signaller, it was only cleared to indicate safe movement onto the adjacent running line from the head-shunt.
This design of disc passed through several stages - originally a yellow bar on a white disc, the yellow was then edged with black lines, and particularly for floodlit discs they found Yellow on Black gave even better sighting at night-time.

Regards,
John

Being pedantic (for a change ) I wouldn't call the "On" position of a Yellow Dummy "Caution". "Caution" is the On aspect of a Distant or Repeater Signal - shown as a single yellow - it is a Running Signal indication. A Yellow Dummy is a Non-Running signal - and all Non-Running signals indicate permission to move as far as the line is clear prepared to stop short of any obstruction.

The difference between Red and Yellow dummies in modern practice is that Red Dummies may only be past when "Off" for all routes while a Yellow Dummy may be past when "On" when the route is set for Non-Running routes (i.e. head shunts and other Non-Running sidings) but may only be past when Off when the route is set onto a Running Line (i.e. out from sidings/Non Running lines).

Yellow dummies have been being phased out since about 2000 - I'm afraid I don't know the exact date. Since the naughties they have been banned from being installed in New Works and amendments.

An alternative to a Yellow Dummy is to provide a Red Dummy which is kept "Normally Off" when the route is set for the Non-Running route(s). This is sometimes elaborated by there being a second Red Dummy in the opposite direction which also "Normally Off" when the Non-Running route is set - when the Dummy is power worked or a Position Light the two (opposed) signals may be on the same control... Bear in mind that the authorised movements are "prepared to stop short of any obstruction".

On development - the thin yellow bar with a vertical black stripe became replaced by various shapes of disc quite quickly in most cases. The various combinations of yellow on black or white seem to be more of e Regional variation with preference for one or the other tending to persist to the present. I do suspect that Yellow on White came first.

I hadn't noticed the typo.

A massive amount of effort culminated today (22nd August) in a track-laying party at the box.
We'd levelled off an area in the NE corner of the site close to our Midland Railway ground frame. Today we laid geotextile and sleepers:


Using one of the few permanent way tools we have, one end of the first stock rail was lifted onto a large trolley we have:

A 'dolly' (steel plate with wheels) was placed under the other end and the whole rail moved to the far end of the site where it was lifted into place:


The second stock rail was moved similarly, and finally the point blades (first one seen here):

(As Bear 1923 could tell you, that's me at the front of the blade!)

The end result of the day's work:

We need to adjust the track and sleepers relative to each other before the former are screwed down to the latter. It does look as though we shall be able to recreate the Talyllyn Railway's 2ft3in gauge, which is rather nice as that's where the point came from.
(Note, by the way, our first 'leaf on the line'!)
Lot of work to do to sort out the steelwork to operate the point from the ground frame, ballast the track etc.

John

those are impressive numbers John.

When's the next one???

QUOTE (Bear 1923 @ 10 Sep 2018, 08:16) <{POST_SNAPBACK}>

When's the next one???
We resume Sunday Afternoons, 2-5pm, on the 23rd September, 14th & 28th October, then switch to Winter opening on the 2nd Sunday of the month only for the 11th November and the 9th December.

We have just started working out the open days for 2019 - I'll publicise these when they've been agreed by the Trustees.

Regards,
John