Flying Scotsman

Like everything it comes down to the skill of the people diagnosing the problems!

 

Didn't you know that Civil Servants are really our armed forces reserve? Can't actually call them that as it would upset the pacifists.:behindsofa:

 

Someone posted that the frames were realigned when Dr Marchington paid for its last overhaul , if that was the case, how come things can be so bad now? its my belief that the current problems stem from that period, if an engine runs on the mainline with frames being out of true then stresses are going to be placed on horn guides, on stretchers, and any other parts you would expect to be effected by this, the problems found on 4472 are now well known , im not an expert by any stretch, but how else do you explain it, I agree that York has worked wonders with past restorations, but i would guess that 4472 has been beyond their expertise , i would go as far as to say that most railway workshops would have thought again if asked to undertake this restoration given the state of the engine as purchased

 

Dont think running it with an A4 boiler at 250psi, with the extra tractive effort it could impose of the frames would help either....

As other people have said, the frames are 80 years old, she has done 80 years of work, if still working they would have been replaced by now.

Lessons are undoubtably being learned all of the time from FS, im sure other future restorations will encounter similair problems.

 

i belive some of the cracks have been claimed to of been caused b its australian visit, and seeing how she bounced along they're track im not suprised!

 

You may very well be right. I am 99% certain it was Peter Nicholson's book which mentioned the realignment of the frames under Marchington, but I don't have my copy to hand at present so I can't check that. However, one cannot rule out the possibility that either the job was not done correctly, or that the loco was so maltreated during her subsequent spell of operation that the good work was undone (although, not being an engineer, I can't make any suggestions as to exactly how that would have happened). However, we have to try to see things as they would have appeared to the NRM back in 2005: at that time, did they have reason to believe that the frames would need to be realigned again? If not, then that might explain why they didn't hunt for the kind of defects that might be caused by misaligned frames.

 

Wonder how the frames were 'realigned'?

 

Checking for frame alignment is quite easy. There are various optical or laser systems readily available.

 

Oi don't you dare pinch my hammereace: It's silver and I acquired it from a chap called Maxwell.

 

Given the history of frame cracking with the A3s, I doubt they're 80 years old.

 

That is a question that i would guess will never get answered fully , but i dont think that Southall have any optical alignment gear, so its my guess that they would have relied on mk1 eye and a line , not the most accurate way of doing it ,unless you know exactly what you are doing , they could have borrowed a set from somewhere also but how many workshops had alignment gear in those days?

its a pity that Bongo no longer posts on here, he would have the answers and could prehaps explain why sometimes things are done a certain way .

 

I wasn't so much alluding to the measuring process as to the means of correcting any misalignment, and whether or not this could have induced any of the cracking?

 

I doubt that the frames themselves were 're-aligned'. It probably meant that the axle centrelines were set to get them as near parallel with each other and at right angles to the cylinder centrelines.

 

My apologies if this has already been covered, but I cannot find an obvious reference to it; were Gresley's A3s any more or less likely than other pacifics of similar design to suffer the cracks that have been found? I would assume not given that the designer had considerable experience in locomotive design!

 

So just tinkering with the boxes and horns in reality then?

 

If you have the back issue of Steam Railway with the interview with Chris Beet he mentions removing the bow out of the frames at York.

 

But we're talking Marchington days I thought?

 

The Gresley A1/A3s certainly suffered a lot more frame plate problems than the A4s.

 

If you can find it read it.