BR Standard class 6 No. 72010 'Hengist' and Clan Discussion Thread

Yeah, I'd say go for it too - would be interested to read. (And make sure you cover livery details of the casting boxes…)

Tom

 

Ah yes Whitworth thread. It was Kevin Duckworth of Cosworth fame who said that the the UK had the best thread form in the world, and they surrendered it without a fight. We have done that with lots of things, dock loading hoses, welding hoses and even simpler stuff like shot blast hoses. Are we useless? No, but those who would betray us are, and are frequently to be found in the House of Commons or the CBI.

 

If the man from Stockport got it better with 55ºcompared with 60ºfor Unified and ISO where does that put Mr BA with his 47.5º?

The mention of umpteen types of 'ose brings to mind the two Ronnies sketch.

 

Yes Brian, but not on this thread please, there is a specific thread for MIC isn't there?

 

Mick, is there a thread for thread please.
Oi Fred , put the thread for thread on mic for mick would you

 

Sorry about the hose ref. I used to work in the industry and these were examples of products whose standards were revised downwards, lowest common denominator etc. to the advantage of the bottom line and nothing else.

 

Forgive the mischievous moment. Sometimes the debates are, annoyingly, about the most trivial of things and I had a moment of weakness.

 

Love the Two Ronnies sketch Brian. And please don't stop with the 'trivial' chat. It brings a new and interesting twist to the thread which still, very much, relates to 72010 after all we are relying on your skills for our patterns!

 

The first of the new frames plates nears completion on the profile cutting machine at Stephenson Engineering (Manchester).
This momentous occasion is the commencement of the frame assembly programme that wouldn't have been possible without the support of our loyal members and donors.
The second frame plate will be profiled today (Friday) at Stephenson Engineering and the both plates dimensionally checked. The task of welding in the new horn guides, which are already at Stephenson’s, can then begin. This will be followed by a thorough Non Destructive Test (NDT) including Magnetic Particle testing and a Dye penetration test. This possibly all sounds very simple: but when you consider that the frame plates need to mounted vertically to allow access to both sides to allow balanced welding procedures to avoid distortion to the frame plates or horn guides, it becomes apparent that it is not so simple after all.
After this is completed the plates will then still need to be drilled, with all holes being undersize by 1/16th of an inch, ready to go on to Ian Riley’s works for fitting of the frame stretchers.
I think it is safe to say that as of Thursday 28th November 2013 the future of Hengist is assured. The build programme has started in earnest.
There is still time to get your name on our Frame Appeal wall of honour by becoming an individual donor, or better still if you are not already a member, please ‘Join the Clan’ and set up a regular standing order – the “Cost of a Coffee” a week would be a most valuable contribution. See our website, http://www.72010-hengist.org/index.php, for details of how to join us in our adventure. The dream is becoming a reality.

Remember:-​

Together we can achieve the extraordinary.​

 

Are you sure that you are doing both? Can't see any logic in that. They are both going to find surface flaws. MPI is best on steel but doesn't work on non-magnetic materials so you use dye pen, which you can also use on steel if you haven't got MPI. No point in using dye pen if you have MPI, though.

 

The tests cover the full frame manufacture including the horn guides and the welding of the horn guides to the frame plates.
Dave

 

But why were they welded and not cold riveted as were many other engines? FS being an example . . . . originally.

 

The horn guides on BR pacifics and 9Fs (and Bulleid pacifics) are a simple U shape, positioned centrally within the horn gap, the frames being set closer together to allow this. That's how they were done by the Southern and BR too: welded, not rivetted.

 

F S's horns were originally held in place by fitted bolts.

 

The horns on the Merchant Navies were larger castings and they were fixed in place using fitted bolts.
Well over half of the 9Fs had large cast horns that were held in place using cold turned rivets.

 

Sorry for my error. I re-place the question - But why were they welded and not attached using fitted bolts or cold rivets as were many other engines?

I understand how the frame plates on some engines were placed centrally on the horns. It the attachment method I'm asking about.

Looks good at Stephenson Engineering above.

 

Because they are a more modern design, and welding gives a more secure construction I'd guess?

 

An interesting question, given that welding produces stresses. I wonder if any of the Bulleid experts on the forum know why the man used the bolted on horn design on the Merchant Navies, yet used the welded design on the WCs/BBs.

 

Probably simplicity of manufacture but that is only an educated guess. Welded horns is only going to involve a bent bit of hefty-metal, whereas fitted bolts is really going to require a casting and machining.

 

Firstly the Clan's horns are welded, and they are a steel casting not just "a bent bit of hefty-metal".

At the risk of being spectacularly wrong I'd hazard that Bullied used welded horns for the WC/BB to save weight over the MNs. Getting to the minutiae of fixing methods; I'd be interested to know the pros and cons of fitted bolt v cold set rivets.