70000 Britannia

7Fs are known to waddle as well when working hard.

 

Isn't this a feature of outside 2-cylinder engines that both inside cylinders and 3-cylinders designs was hoped to eradicate ?

 

Sorry, - I wonder which fitter Footbridge talked to....

 

Yes, its nothing to do with wheel imbalance as 3.40 onwards in this video shows

 

Very unlikely as the only derailed axle was the trailing axle on the bogie.

 

OK just wondering if things could have been forced whilst either derailing or reversing it back onto the track driving it up blocks. Appreciate that it was the bogie that was off, but getting it back on must have applied equal force to the front drivers in the opposite direction to the bogie being pulled back onto the rail.

 

The latest issue (193) of Heritage Railway arrived in the post today and a report in the Main Line news section says she will probably be out of action for another month before being run in on the MHR. They really haven't had much luck with the repairs to 70000. The original problem which saw her withdrawn from service nearly three months ago was a vibration caused by a problem with the front driving wheelset. Problems were encountered at the SDR as they did not have the correct materials (to BR spec.) so they had to be bought New. The axle repair was started at the SDR and was completed at Riley's works at Bury. Delays were also encountered with a new set of Timken bearings from America. However, if the repairs do not solve the vibration problem the other two driving wheelsets will have to come out as I mentioned in a previous post.

 

That makes grim reading!

And just where do they trace these problems back to - her recent spell at Crewe?.............

Either way its looking touch & go for the gala, especially if the other wheel sets have to come out.

 

Why does it always have to be someones fault?

 

Bearings don't last forever.

 

I'm not saying it is, BUT given that she spent quite a time at Crewe I surprised that nothing was picked up at the time........ so can we assume that this is just something that has manifested itself over time?.......

 

If its a bearing issue, anything is possible, it may be an overtime thing, it could be brinelling during road transport ( if there has been any that is i do not know) or it could be one bit of dirt that found its way in to the bearing,
roller bearings can be like light bulbs, fine today, but tomorrow who knows,

 

As I mentioned in an earlier post I would imagine the crash in Norfolk and the derailment on the NVR didn't do her much good.
IIRC 45305 suffered with several problems after she was involved in a crash at the GCR and had to have an overhaul to get her fully fit again for ML duty.

 

Thank you for that - you learn something new every day - and being no engineer, could mean a lot.

As for on and off wagons - Cromwell does it countless times, and yes "Brittany" has been on and off wagons, SSS III springs most recently to mind! Though she's not on "the wagon" as much as Cromwell Lol!

 

I'd forgotten about that!

That'll be the shock wave (whiplash) going through her.......... same as probably what's buggered up the Duke!...........

 

Plenty of locos have had low speed impact and lived to tell the tale afterwards..

Indeed at the mayday parade in Wolsztyn it's almost part of the days activities for something to drop off the turnable, see burly guys swearing in Polish with lifting jacks and easing the loco back on the track, all before it heads out at 5pm with a trip back to Poznan without so much as a quick glance over.
Not trying to down play the possibilities but counter balancing, lets not read too much into it either.

 

It may well be the best approach to go back a few stages, remove all the wheel sets and then double check the frame alignment as is part of the recent discussion on the Flying Scotsman thread. While this is being done the wheels, axles and bearings can be fully assessed. The crank pins should be checked for quartering and the rods for accuracy of centres. The existing balancing should also be checked and rectified if required. Or, put another way, take the required time to eliminate all possibilities.
Same as should have been done with 4472. At the end of the day no one really minds the time that you take but the quality of the end result is another matter e.g. 34092.

 

you got the job then!
congratulations,

 

I believe you are correct, due to the stresses involved on something that wasn't built to endure them.

A short wheel base 0-6-0 or similar will probably be OK due to rigidity & weight, but a larger lump like a Pacific with its size & weight - probably not, BUT that begs the question, why are some loco's of the same class prone to problems and others not - lets face it if the NRM were concerned about Cromwell, she'd be moved away from the GCR to a mainline connected railway!