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

The website is well worth a perusal again. There are have been some general updates to the situation which make very interesting reading as in bogie and cylinders news at least.
https://www.theclanproject.org

 

Your link has an error in it (the .php is not required) - the correct link should be:
https://www.theclanproject.org

 

Thanks for spotting that mistake, ghost. I have edited it accordingly.

 

The link as displayed has no php at the end but if you hover over it or click on it the actual link still has the php.

 

Providing Covid restrictions are lifted as planned, the Clan project will be holding an Open Day at CTL Seals premises in Sheffield on 26 June. You can find details here https://www.theclanproject.org/Clan_OpenDay.php. Come and see what we're up to! We will be very happy to answer your questions

Ian

 

Latest update to Project website shows how much care and precision is being taken with this work.
If I can get it right this time, look at https:/www.theclanproject.org
The Open Day could have some interesting news and sights for those lucky enough to be there!

 

Lovely!
I wonder if any of this was done on the production line back in the day?
Is this the sort of thing that allowed for "good" and "bad" engines of the same class?

The only frustration about making a one-off is that the specific fixes can't be reincorporated into the next one.

But hopefully the B17 boys and CTSeal will use the the knowledge on their project

 

Very interesting, and good to see that so much care is being taken with the build. Let's hope that this pays dividends in the years to come... Maybe it will reduce the amount of frame plate corrosion due to preventing water ingress.

Richard.

 

..not only that but increased efficiency of steam passage from cylinders. A solid metal to metal contact is better than a gasket filling the joint, not that there would have been that in this case. Together with the careful machining of the lead into the spider there should be a smooth exit for the steam now. I would suspect that once the cylinders are in place there is little further improvement can be made to these 2 joints.

 

Just to add a further comment to this debate.
When it is time to fit the cylinders to the frames, this process will be applied to the joints between the cylinders and the frame plates, for exactly the same reason - to ensure a steam-tight seal. That's a little way off as yet as Tony is still working on the pattern for the cylinders. A long and complex process that is progressing steadily. Looking forward to seeing the complete frames with cylinders attached. That will be a sight to see I am sure.

 

An additional thought on this process.

When the cylinders are fitted to the frame plates, this process will be gone through again for the joints between the cylinders and the frames for exactly the same reasons, to ensure a steam-tight seal. Be a little while before we get to that point as the cylinder pattern is still under construction - a long and complex process.

Keep your eyes on the website for updates. And I hope to see some of you at the Open Day. Please come along. You will be most welcome.

 

Sadly I cannot make the open day as I foolishly booked my first holiday in two years that week. I am starting to get excited about Hengist now as the big tasks are all progressing nicely and having the support of CTL is a massive bonus to the project. I hope CTL are getting something out of the relationship themselves as it must be an opportunity for them to showcase the breadth of their engineering capabilities to their customers.

 

It's a shame you cannot make the open day, but there will be others in the future.
CTL uses Hengist as part of their apprentice training scheme, as some of the skills needed are not to be found on other work that they do, so she is regarded as an asset. When we had the small sections of frame hot riveted numerous members of the CTL engineering staff came to watch as they had never seen it done before. And any tour of the works for CTL visitors normally concludes at what is currently referred to as "Hengist Corner", much to the surprise of those being shown around as they have no idea that a steam locomotive is under construction.
So it's a symbiotic relationship. We both get good things from our being there.

 

This weeks update might raise a question for some people.
Why do you need to radius the corners on the frame/extension plates, especially to such a small amount as 1/16th to 1/8th inch?
My apprenticeship taught me the reason but I wonder what reasons others know.

 

I’m no mechanical engineer but I’d say stress relief to prevent cracking?

 

I dunno; that's usually on an 'interior' corner, where in-plane forces are trying to 'widen' the angle formed by the two sides, thereby producing a stress concentration at the corner. In the image, he seems to be working on an exterior corner; I can't see a direct mechanical benefit to removal of the corner material there. I await enlightenment! (Maybe it's something as simple as 'sharp corners are more likely to cause injuries on unintended contact'?)

Noel

 

There’s a photo?


Sent from my iPhone using Tapatalk

 

The 1/16" to 1/8" radii on the corners, unless otherwise stated, as noted on the frame slotting drawing, is probably a combination of what has been stated in the posts above.
Most engineering drawing have the words " Break all sharp edges unless otherwise stated." on them.

 

Yeah, top item in Latest News. (I couldn't find a way to link directly to that item, so that link won't be good forever; probably the way their site is organized, I suspect that page is manually edited - items from before May don't seem to be in the News Archive.)

Noel

 

Nice comment Noel, I refrained from putting a link up knowing my problems with them!
I can assure you that there were lots of News items before 12th May, strangely they are now under the Construction section, Build Diary. Hmmm, I wonder why 2021 is missing from News Archive, no doubt Ian will respond with an answer.
Meanwhile, the reasons I know of for removal of sharp edges are:-
a) reduction of dangerous sharp edges, especially in areas of manual activity
b) reduction of stress concentration around edges/corners (particularly with rough/jagged edges/corners where indentations could encourage a failure)
c) sharp corners cause damage to slings and chains during handling.
In my day we did not have the luxury of grinders for that, it was hand filing mainly.