Current and Proposed New-Builds

4709 has a new/updated website. https://www.4709.org.uk/

 

That's been around for a while, but it does seem to have been re-organized; my bookmarked Latest News page there seems to have disappeared. The new blog page is a welcome addition/replacement, though. Good news about the cylinder patterns!

Noel

 

Hence I added 'updated', although unhelpfully it doesn't give any details that I can see of explaining how visitors can support the project unlike its predecessor.

 

Each item is dated, but only by month and day, with no indication of year. For example "Sat at Didcot for decades, 4709’s tender will soon return, coupled to our 2-8-0 monster" is dated MAR 5. Obviously not this year, but was it 2019 or earlier?

 

Hi everyone. I’m back, and am safe at the moment.
I’m sure everyone knows of the current situation regarding Covid-19 and the impact it is having on the Heritage Railway scene.

 

Excellent! A couple of questions:

1. What are the cylinders off which are shown in the photo on the blog?
2. Where will 4709 be moving to?

Good Luck with the project once all this Covid 19 stuff is over!

Richard.

 

1. Those are the patterns for the cylinders, and
2: I do not know.

 

No, I was meaning the cylinders in this photo:

Richard.

 

2861

Keith

 

Aha! Cheers Keith, it makes sense now - The new smokebox won't fit the saddle on 2861's cylinder block, it's a larger diameter.

Richard.

 

They have changed the plan now and are having new cylinders cast to the original design.

Keith

 

Two questions:
If the cylinders from 2861 are now not going to be used, why are they still attached to the frames in that picture?
And is the plan still to fit a No. 7 boiler in the fullness of time (with the saddle on the new castings dimensioned accordingly) and to make a temporary arrangement to take a No. 1 boiler?

 

I think it hasbeen announced that they have now decided to go for a new No. 7 boiler.

 

As far as I am aware the plan is to build a new No7 boiler which would then fit the new build original design cylinders/saddle. I don't think they are going to use the No1 boiler now. I assume the cylinders are still in the frames for rigidity purposes and maybe some measurements, until such time that the new cylinders are cast, machined and can be swapped in.

Keith

 

The cylinders shown in the photograph aren't physically attached, just held in place by gravity.

Bob.

 

Out of interest, how much a year are the 4709 group currently raising?

 

To reiterate what was posted back in May of last year :

Cylinders:
While the original intent was to use the spare castings from 2861 plans have changed. First off the pair need to be split to allow confirmation of the integrity of each. The possibility exists of finding something nasty in which case all the effort is wasted ..

Assuming all is OK the block still has problems as it stands:

• As said, the curvature of the saddle is wrong for the no7 boiler (see below),
• The boiler pitch is too high for the NR loading gauge - about 2 inches needs to be removed
• Once you have done that the block is still too wide for the NR loading gauge severely restricting main line usage - if any.

So a lot of work to make the existing block usable and the decision was taken to go for new with a few detail changes to take care of these problems. The latest newsletter shows the poly patterns for these complete and the casting of the new blocks was apparently only a few days away when the foundry shut down due to the virus situation.

The 28xx blocks are probably still on the frames as having been in position to help with the setting up of the extension frames etc, there has, to date, been no need to remove them - and wont be until the replacements are ready in due course/eventually.

Boiler:
The available no1 boiler is in ex Barry condition with all that this entails. It could require a lot spending on it to make it serviceable and probably more at the first 10 year overhaul and more after that. New boilers are currently under construction for other projects so the capacity has been proven to exist. Hence the decision has been made to go for a new no 7 boiler and ensure (hopefully) a trouble free period of operation. So the plan to use the no1 boiler even as a temporary measure has been dropped.

M

 

Thank you for this!

So, is the boiler centreline actually going to be lowered by 2" from original then, or is it sat at the correct height when using the new cylinders / saddle?

Sorry for all the questions!

Richard.

 

Is the no 7 boiler similar in size to the castle boiler ?

 

Bigger. The Castle boiler is basically a Standard 7 with a reduced diameter barrel to get the weight down.