71000 Matters

Me too. I also think the Caprotti is what gives the Duke a unique personality but its not the only thing that makes the Duke exceptional.

 

Appeal launched for steam locomotive "71000 Duke of Gloucester": https://www.railadvent.co.uk/2019/0...team-locomotive-71000-duke-of-gloucester.html

Please help so they can finish the restoration of this very unique mainline steam locomotive!

Knut

 

How can something be very unique? It is either unique, or it isn't!

 

In the long run for 71000 to have new rollers on her and new tyres for its driving wheels , And the caprotti valve gear to new parts to say only 2 locos survive with caprotti valves the other 73129. But it will be worth it in 2020 when duke of gloucester is back the best out of the 2 caprotti,s and mainline certified, the standard 5 will have quite a wait in the overhaul queue at swanwick jct yet.

 

I think I’d cut a Norwegian a bit of slack in his use of English! Certainly better than most of our attempts at Norwegian, I suspect.

Tom

 

I'm sure it doesn't matter, most of us understood what our Norwegian friend was saying...........thank you for your contribution.......

 

I believe it's a case of differences in the cam profiles, giving slightly different valve events. They've decided after all that the originals were a bit better, but I don't think either set of profiles was bad. The beauty of Caprotti is that it allows optimum exhaust valve openings over the range of inlet cutoffs, rather than the exhaust and inlet events having a fixed relationship as you get with piston valves.

 

Apologies i really dont remember the ins and outs, whether its reversing a change in Cam Profiles,Lifting Valve /Spindle profiles or just a reversion to original spec materials. One s suspicion is that whatever tweaks were made are now thought to be detrimental to the longevity/ reliability...

 

As long as they don't put the ashpan back to what it originally was!!

 

Before criticising someone's grammar, perhaps you should consider that 240P15's first language may not be English.

 

Ditto the exhaust!

 

Where can I read about the exhaust before and after?

 

Not sure but it was a standard Swindon double blast pipe originally. Now a Kylchap I believe.


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I think it is a double kylchap and the Duke does have a fantastic sound at speed - a real staccato, almost machine gun like beat.

 

Yes it's a double Kylchap.

 

It was described in "71000 Duke of Gloucester The Impossible Dream". Part 2 is available from the Trust but not the original booklet (which was not identified as "part 1"). Second hand copies may be available, but perhaps we should ask the Trust for a reprint.

 

See here: https://www.dukeofgloucester.co.uk/?section=locomotive&page=Modifications&subpage=Restoration

(and also interestingly here about the precise form of the brick arch, something I had not come across before): https://www.dukeofgloucester.co.uk/?section=locomotive&page=Modifications&subpage=Mainline+Running

Tom

 

the original was , I think , a Derby confection which didn't work well

it was sent to Swindon FAO Sam Ells . it returned from Swindon with (allegedly ) 2 Dean Goods chimneys ( and possibly blastpipes) stuck together . that didn't work either but it made a lot of noise and burnt a LOT of coal
. Swindons interest in it seems to be somewhere south of low.

5% cut off seemed to be a popular setting , probably to avoid running out of coal.

I saw quite a lot of it - nobody seemed to want to clean it much either