34039 Boscastle WC class

In addition to the Boscastle Official Supporters Club, with its monthly e mails, there is now a Facebook site for the supporters and other interested people, who may prefer that method of communication.

 

During the shed tours it was good to see that parts of the boiler cladding were being prepared. These fit on top of the firebox.

 

There will be "Boscastle Shed tours" on the Saturday and Sunday (Nov 16th, 17th) of the GCR Last Hurrah Gala, so an opportunity to walk up to the shed and go with a guide to see the work going on inside. The tours are free, but a donation towards the overhaul of Boscastle is appreciated.
More parts for the tender have been made and fitted.

 

There was a letter sent out to the shareholders last week following the AGM. The directors are looking for more help as the long standing and very valued Company secretary (John Woodward) has not stood for re election and is retiring. Any offers of help will be Much appreciated ...... The job can be split up to suit applicants skills. More details via our website or PM me.
We are close to getting Boscastle back into steam but need fresh people to join our team.

 

The Shed Tours were very popular yesterday with a steady flow of visitors from 10.30 to 4pm. There were several parts of the firebox cladding on view that had been prepped and primered. So steady progress by the team.

 

Some of the backhead (?) cladding which will need repair sections welding in place.

 

Seasons Greetings to all on NP from the Boscastle team.

 

Boscastle shed Tours are again being offered during the GCR Winter Steam Gala. These take place on Saturday Jan 25th and Sunday Jan 26th from 10.30am to 3.30pm at regular intervals. They are free but a donation towards the overhaul of 34039 is appreciated.
If anyone is looking to help, either with the physical overhaul, or more generally with the Boscastle team, please let us know on here or via the Boscastle website. It is a great time to come on board as the locomotive is close to getting its boiler finished and then back into service.

 

You are quite right.

Certainly at 300 psi you need/require a steel firebox - and though few people had such pressure, whether in the the USA or Germany, they had steel inner fireboxes when they did: with the increased pressure the strains on the boiler increases and at the same time the heat in the boiler -water and steam - increases while the strength of the copper decreases with the rise in temperature. At 300 psi/20 bar you are beyond the point where copper is practicable.

I suspect that if you wanted to substitute copper for steel in a Merchant Navy boiler there would be little difficulty because, first, they had a solid foundation ring and second, there is no harm in having more water space around the firebox. Though I would certainly get the obvious calculations done and checked.

However, the Light Pacific boilers had a lightweight foundation ring of plate bent into a trough and if you needed a solid one it would be decidedly heavy. You could perhaps lose a third of the extra weight by reducing the stay length to all you need for a copper box but you would have a wider span in the firebox crown to recalculate for and the grate would become a loose fit. However, if you could trust the new copper to fix satisfactorily without a solid foundation ring, it would be amusing if it turned out that it cured the outer corners of the firebox shell cracking - this they did on the West Country's boilers but not the Merchant Navy's with a solid foundation ring and also extra length - 18 inches more.

To my knowledge Nicholson siphons etc. were always only done in steel.

 

Did the GWR 1000 Counties use a steel firebox?

 

No.

 

The pressure on the Hawkesworth counties was indeed 280 psi with a copper firebox and standard Swindon staying and it is fair to say there was no immediate catastrophe from this. But the pressure was reduced to 250 psi, which of course the Kings ran with fine.

The same the same pressure and the same reduced pressure obtained in the Bullied Pacifics which was after the steel inner fireboxes were failing early. Wether there
were any equivalent troubles on the Counties I have never heard any detail - however much one might think it likely- it is not clear there were let alone what exactly they may have been.

 

In his book West Coast 4-6-0s at work, C.P. Atkins reports that Claughton No 42 was fitted with a single thermic syphon in 1921, and the inner firebox would almost certainly have been of copper.

 

There has also been work preparing the inner cylinder connecting rod for its eventual re-installation. Some of the smaller locking parts were stolen and are being re-manufactured.


Connecting rod seen here behind the smokebox door.

 

Thank you for that, quite new to me. Wonder if it might be be possible to date when it was reoved or not persisted with?

Incidently, the second Gresley V4 after Bantam Cock had Nicholson syphons in a steel box which was soon repaced: if the difficulties were first attributed to scaling in the syphons if might explain why they were sent to Sotland where the boiler water was notably soft. (There was another reason at least why they were a good fit for the West Highland.)

 

Atkins records that the boiler lasted five years, doesn't say anything else. As far as I am aware there was no publicity about the fitment at the time and was only mentioned 20 years later when there was discussion whether the V4 or Bulleid was first. Clearly it wasn't sufficiently successful for the experiment to be extended, though it should be remembered that Bowen Cooke had died and the LNWR incorporated in the LMS so the experiment was something of an orphan.

 

I think that various writers recorded the reduction of the 280psi pressures in both the "County"s and the Bulleid pacific as being made to reduce boiler maintenance costs - whether that is a coded way of saying that in practice a relatively small increase in pressure introduced a disproportionate rate of wear is an interesting question! Does anybody now really know? In either case, are there any records of the decision, and more detailed explanation of the reasoning, to reduce the wp to 250psi?

 

There is a comment in “Bradley” (who was no fan of Bulleid’s Pacifics) that reads, with regard the Merchant Navies:

“The Eastleigh boilersmith estimated that the reduction in maintenance and wear would add 80,000 miles to the period between successive boiler lifts”, however Bradley gives no further information about how that figure was determined.

It is also worth noting that the first ten MN boilers, built by North British, were particularly prone to cracking at various points in the firebox, after which there were modifications to both the stays and the thermic syphons.

Bradley also gives the comparative boiler maintenance costs per mile after the boiler pressure had been reduced and water treatment introduced:

MN - 0.24p
A1 - 0.39p
Britannia - 0.39p
Royal Scot - 0.54p
King - 0.91p
Duchess - 1.12p

Whatever else their faults, the boiler was both a superb steam producer and cheaper to maintain than any others of comparable size on BR.

Tom

 

Interesting cost comparisons Tom, thanks.

Oh, and I think you've got a software problem. The fourth word of your final sentence didn't come out as 'excellences' as you surely must have typed?

Bryan

 

If I had been in the upper echelons of BR at the time I would have wanted to know how reliable those figures were and what could cause such big differences.