The team in The Works are pressing on with the overhaul of Sir Nigel Gresley. Locomotive Engineer Darrin Crone provides us with an insight of recent weeks’ work.
This is the 14th update – you can catch up on the previous posts here.
Week commencing 3 March
The dragbox bolting has been completed with the last couple of nuts torqued up. The dragbox was then di-pen inspected. Not an easy job on such a complicated component, so one level at a time was done. The areas around the draw bar and safety link pins have also been inspected and no defects were found. Then on Friday the first coats of primer were applied.
The safety-critical air brake components were retrieved from storage this week. They were given a clean up and we made sure the ports were sealed. These will be sent away for contractor refurbishment so that when they are returned to us they will carry certification and a guarantee.
Painting of the loco frames and major castings around the front of the locomotive continued. The final coat of gloss was applied to the outside-front bufferbeam area. Progress was also made on priming the middle cylinder and the saddle casting.
The boring of the cylinder mounting holes in preparation for reaming continued this week. About half are now completed, however there are some particularly awkward ones yet to do. Depending upon the amount of reaming, the cylinder flange holes may need to be revisited with the borer, but we will see what we get when we ream them.
The coupled wheel springs were given a clean off this week and the spring buckle pins and retaining boxes were removed. The springs will be sent for contractor refurbishment and quotes have been obtained. The pins and retainers were tagged and put in storage, and a start made in moving the parts from over the adjacent pit in to the GUV. We are clearing this area as it is planned to move the tender into this space. Other parts have been moved to the other side of the loco.
In Devon, the wheelsets are progressing with the crank axle on the wheel lathe. At Crewe, the tubeplate has been formed and will be sent for machining shortly. Repair work to the firebox copper side sheets continues at Llangollen and an access platform is being assembled so that work can commence on the top of the firebox.
The splashers on the left of the locomotive were refitted this week. As they are secured with dozens of bolts it was decided to fasten them by bolting through every other hole for the present. When they are all up we will put the rest of the bolts through.
During inspection of the air pump it was noticed that the clack valve springs show signs of wear, so it is planned to replace them. A suitable, commercially available spring specification has been identified. The cylinder end covers have now been di-pen inspected and no defects were found. That just leaves the steam cylinder requiring repair and the other cylinders will be honed to clean them up. The studs are being removed from the steam cylinder to aid repair.
The pistons have received a detailed inspection prior to their refurbishment. Particular attention has been given to the end of the piston rod where it meets the head and to the cotter slot and taper that fits in to the cross head. No cracking was found but one of the tapers shows some marking. This will have to be carefully removed.