4079 Pendennis Castle Overhaul

Morning all,

I am working on the Overhaul of Pendennis Castle at Didcot Railway Centre and thought I'd post an on going thread of updates. I've been on the Pendennis team for pretty much exactly one year now.

When I arrived on the team the tender was pretty much complete (just awaiting the mainline things). The locomotive it self was also looking very complete, fully wheeled with all the external motion in place, the cab was also prominent (The cab sides, and front where all in place). Most of the running plate was in place, all the brakes wee in place (and working!) New cladding was also in store, along with all of the valve gear.


Since then a few things have been accomplished, such as the preliminary boiler inspection which has stated that for an 80 year boiler is in very good condition and very little work is really required on it, it has received the heat absorbent silver paint as seen here.


All the valve and cylinder liners have all been fitted, but the inside and outside left cylinder have had to be removed. The actual valves themselves have been completed (by your truly!) and have been trial fitted, and are now in store awaiting the fitting of the last cylinder liners. Since completing the valves I've been 'borrowed' to help fit the TPWS gear to the tender. Which the bracket for the TPWS reciever has been pretty much completed and is just awaiting a little bit of drilling before it can be fitted properly.

That's all for now, I will try to remember to get photographs of progress, but until then here's a picture of Her boiler being turned on the turntable.

 

Thanks for the update - nice to see good progress being made - keep the updates coming. You can never have enough running Castles, especially single chimney ones!

 

Crikey that's coming along nicely! Cheers for the update.
Henners

 

Blimey, i never thought they welded them up that well 80 years ago,
Just goes to show, even the GWR welders were better than all the rest.
God bless em.

The Melter

 

I expect the boiler isn't as old as the loco, it was most likely heavily rebuilt by BR before ending up with 4079.

Glad to see progress with the old girl, It'll be nice to have another single chimney Castle out on the big railway.

 

List of boiler changes & loco history here. Although the actual boiler age is not given.
BRDatabase - the Complete British Railways Locomotive Database 1948-1997

 

The boiler was first fitted to 5086 on the 28/12/1937 according to the database.

 

Boiler history here.
BRDatabase - the Complete British Railways Locomotive Database 1948-1997

Makes it 75 years old, but only did 27 years "service" work.

 

I expect the only part of the boiler that is from 28/12/1937 is the number. When you think about the sort of work that is carried out on a boiler these days after 10 years service... I expect a lot of Pendennis's boiler is relatively new.

 

Like Triggers broom (17 new heads and 14 new handles )

 

HAHA! Oh, I do love good ol' Only Fools & Horses!

 

Oh yes, of course, I think the current boiler is (only) 50 years old, that's what our (very well educated) leader says!

 

To almost completely get off the topic I note that Std1 and Std 9 boilers were being built as late as 1960... I wonder what the newest surviving GWR design boiler is!

Because new boilers were being turned out that late (high superheat ones of course) I presume that almost complete rebuilds of an old boiler wouldn't have been worthwhile. I suppose the economics of supplying a new boiler are rather different when you have a boiler shop with all the equipment ready to turn them out... Cook says in Swindon Steam that "in general the outer steel firebox, particularly the upper portion, remained intact throughout the boiler's life", but it seems that tube plate, backplate and inner fireboxes, sometimes in sections and later on with welded seams, were routinely replaced.

 

Must be one of the newest boilers around, then!

 

Well now, I have been accused of some things in my time but being well educated is a new one...

All the best,

Team 4079

 

Hi All,

A bit more information about 4079s boiler..

Boiler No. 6672 was actually built in 1937 (therefore it is 75 years old - so you were only a quarter of a century out Bennymilk!) and was first fitted to ex Star No. 5086 Viscount Horne (ex 4066 Malvern Abbey / Sir Robert Horne). You could argue I suppose that it is one of the largest surviving major components of one of the Castle conversion locomotives of which, none made it into preservation. That in itself makes it quite a historic thing. I wish it was only 50 years old though...

In terms of repairs this time round, it hasn't required a great deal of work in the grand scheme of things. She had a thicker than specification tube plate (to comply with Australian rules apparently) before she went 'on holiday' so that will be good for at least the next couple of overhauls one would hope. As JimC mentions, it has had many of the repairs mentioned over the years and there can't be that too many out there today that haven't. It does feel a bit like Triggers Broom or Cromwell's Knife but it is in reality no worse that the rest of the locomotive. We have to remember that only the frames are truly No. 4079. The rest is just the assemblage of components formed into a Castle shape the last time she left the works. Even her cylinders aren't the originals... Thankfully, we had to straighten her front buffer beam and while removing some part that had been riveted on for quite some time, underneath were those four famous numbers. No Tyseley Hall type problem there. Think of her frames like a stick of seaside rock with 4079 written all the way through, no matter where you cut it!

Apart from the obvious replacement of consumables (tubes, etc) it has had a the crown and a few side stays, the seam rivets and a few other bits done. There are a few foundation ring rivets left to do along with the grate carrier studs, a few of the holding down bracket studs (these sheared as the brackets were being removed for inspection and were actually ok if they hadn't been seized solid!), a few odd stays here and there and one or two other odds and ends. The only plate work repair to do is ironically not part of the pressure vessel. The dry extension to which the smokebox is fixed is a little thin at the bottom (where all the ash, crud and muck like to live) and will need a repair patch letting in. To facilitate this, and other work such as beading the tubes, it is planned to take the smokebox off. Our boilersmiths seem to have a taste for this at the moment with both Nos. 2999 and 4144 bereft of theirs! They are both having new tube plates though... That stay in the sandy, dry desert didn't do much for her motion but it did all kinds of good for the boiler!

The rather fetching heat proof silver paint was donated to us free of charge by our benefactor, John Scanlon of J&L paints for which we are very grateful. He reliably informs us that this is the same stuff as used on the inside of the engine bays of a certain RAF fighter jet so I hope it will wear quite well on No. 4079...

The further plan for this and next year is to put the motion up soon and then place the unfinished boiler back in the frames so that the loco can be totally 'finished' in its entirety and then carefully dismantled and stored to enable the boiler to be lifted, completed and tested. The next and hopefully last two big ticket items are the smokebox steam pipes (all of them except the two copper ones at the top are U/S and of course all that pretty (expensive!) mainline kit. It is all down now to that age old locomotive restoration triumvirate of time, money and a bit of luck.

Now, where are my spanners?

All the best,

Team 4079

 

Does that mean the boiler lagging is around the horne?

I'll get my coat...

Seriously though, thanks for the update!

 

Don't be silly, the amount you know of other engines and of Pendennis alone, gives you that status

So the boiler's not 50 years old, there was something that was 50 years, regarding the boiler and 4079? Was that when it was fitted to Pendennis?

 

Hi Bennymilk,

You might be thinking of her tender. It was built in the 1940s but was only fitted to No. 4079 for her last day in service (9th May 1964) so, it has 'only' been with her for about fifty years!

All the best,

Team 4079

 

Must be that then!

Right, on Saturday 4079 was being worked on again (along with 2999, 1014 and 4144) and I forgot my camera! (why didn't anyone remind me! ) but anyhow more progress was made.

I was once again working on the TPWS bracket, that got a lick of paint today and we started on the weather protector which now just requires a bit of cutting and drilling and that'll be done.

Also some of the pannelling for the chassis was being cleaned up and painted and also some brass fittings were given the 'Brasso Treatment' and I swear they were brighter than the welding! Job well done by that group of people on them.

Some of the internal valve gear was also being cleaned up and tested, didn't get to see too much of that, but I'm sure a good job was achieved by the team doing that.

That'd be all for now Here's some random pictures from Didcot a while back to spice things up a bit
The second King currently at Didcot

And my personal 2nd favourite loco (second to 4079 )