The Restoration of Kerr Stuart 2405

All the five remaining Joffre locomotives has lain out of use in the open air for many years before being rescued and then the four that went to North Wales were on exhibition in the open air and damp welsh conditions for many further years. Hence they were all in a particularly poor condition mechanically, and all require a considerable amount of restoration.

Here we detail the work undertaken to our locomotive over the last 12 years to get it to the current stage.

The locomotive is being finished in Dark Grey Livery lined in White and Black, the orignal livery being indicated in the records as 'French Admiltary Grey', and so we have adopted a colour that we consider is very close to the original. However we doubt the lining would have been applied to the locomotives when built, but the manufacturers picture does actually show the locomotive lined out in a similar manner.

The restoration has been carried out with the aim of getting it as near to original as possible, but ensuring that it is compatible with current standards required to allow it to operate on trains at both our railway and other sites, to ensure that the general public are able to appreciate these locomotives by seeing them in operation. 

Note; The Sections are in alphabetical order, and not in the order of work being undertaken.

AXLEBOXES

On examination the axleboxes were found to be badly damaged previously, and had extensive repairs carried out , mainly brazing the parts back together, they were also badly worn and so the decision was made to manufacture new patterns and cast new axleboxes. This enabled us to ensure that these were now square and true. The original Axle brasses were re-useable and have been refitted.

The Axlebox horn guides were found to be loose, and thereby moving about, causing out of true wear to the guides. The horn guides were removed, remachined back to true and refitted with redrilled  holes in the frames to prevent them becoming loose in the future.

BOILER

The boiler was examined fairly soon after delivery and the first problem was found to be the pin-cushioning effect in the inner firebox and the fact that as the loco had not been operated with a boiler blow-down valve there was limestone scale in the boiler to a level above the inner firebox, which meant that the boiler had been running without proper water circulation and local hot spots, hence the pin cushioning. We got several wheelbarrow loads of scale out of the boiler. We removed the original Brass boiler tubes and the Copper Inner Firebox to enable us to have a more detailed look inside the boiler, and  it was decided that it was repairable, and the boiler shell is currently undergoing repair at a Boiler Makers in the Isle of Wight, with a anticipated completion date later this year.

BRAKING GEAR

The braking gear was found to be badly work, and the brake hangers were re-bushed to take out the excessive play. The original brake  hangars, brackets and draw bars were used but a new brake  operating rod has been manufactured, to allow for some modifications made to the rear brake bar, which had been modified to allow for a steam brake to be fitted under the footplate (to enable the loco to be operated under current regulations). This has involved the manufacture and fitting of a new brake cylinder, and operating rod and crank. The original handbrake has been refurbished with a new screw fitted to take out the wear in the mechanism.

In addition new cast iron  Brake Blocks have been manufactured, and which are a deviation from the original brake blocks which were wooden, but to ensure a longer life and  resilience  to the steam brake operation this deviation from the original was thought to be acceptable.   

BUNKERS

The original bunkers were beyond repair, and new ones have been constructed, using rivets where required, and mainaining the original design, with the exception that the right hand bunker has been modified to accommodate the necessary air brake piping and gauges. The bunkers have taken a lot of effort to construct, resulting in a truly authentic looking pair of bunkers, down to the riveting detail replicated from the original lococs.

CAB

The original angles and other structural parts of the cab have been rescued from the remains of the original cab, and will be incorporated into the new cab, which is being constructed to the original drawings. The cab spectacle plates have already been cast, and the cab front has ben fitted, and the cab back will be commenced as soon as the bunkers have been completed. The cab roof has been manufactured and awaits fitting fairly soon.

CHIMNEY

The original balloon stack chimney had been replaced many years ago by a simple stove pipe chimney, however upon examination it was found that the original cast chimney base had been used as part of the replacement chimney. Therefore this has been retained, and a new replica internal chimney swirl has been manufactured, and so the chimney now requires the conical  rolled platework manufacturing and assembling. The component parts for the chimnety have now been constructed, and await assembly at the final stage in the restoration plan.

CYLINDERS

The Cylinders were removed and assessed and the decision made to re-bore the cylinders  to take away the years of wear in the bore. The Piston rods were metal skimmed and remachined, and new piston rings obtained and refitted to the newly made piston heads.

The slide valve faces were skimmed to ensure their trueness, and due to the wear on the Slide Vales themselves, new patterns were made and new slide valves cast in brass and the machined to suit.

FRAMES

The frames were completely stripped down and assessed and the rear portion of the frames were so badly corroded a section of the rear frames were cut away and new plates welded in. luckily this did not affect the structural strength of the frames, as the replaced portion is purely under the cab. In addition the Front and rear buffer beams were renewed, but the original cast iron buffer beam weighing some 6cwts,  was re-used and refitted.

In addition alignment check's were made to the frames, as part of the process of re-fitting the axlebox horns guides, and additional strengthening to ensure correct frame alignment has been fitted. There were some cracks found in the top of the axlebox cutouts in the frames, and  these were re-welded to ensure the frame was returned to as near to 'as new. condition.

In addition the Well tank between the frames received attention, with the tank top being removed, and access gained to the Well Tank. It was found to be filled with Granite Ballast, as the loco had latterly be used without utilising the Well Tank, and so the previous owners had obviously replaced it with Ballast to try to maintain the loco's stability.

The well tank was restored, and new spring pushrod pipes refitted, together with a new tank lid fitted. The tank has been pressure tested, and the aim is to operate the loco with a fully operational well tank.

INJECTORS & FITTINGS

The locomotive  was found to have the wrong type of injectors fitted on acquisition, having a traction-engine style injector fitted. However the opportunity to obtain two original backhead style injector bodies was taken. However these had the injector cones removed, and so new cones are currently being manufactured, and it is hoped that this will result in a fully operational pair of original style injectors.

The other steam fittings have been sourced and many await fitting in the final stage of the restoration.

LUBRICATOR

The locos were originally fitted with a Detroit lubricator,which had long since disappeared from the locomotive. However we have located a correct Detroit lubricator for our locomotive, and it is awaiting overhaul before fitting.

MOTION & VALVE GEAR

The locomotive had a complete set of motion when delivered, however it was in a very badly worn state and upon dismantling and assessment, it was decided that most of the bearing were worn beyond repair, and many of the pins were also in need of replacement.

The slide bars were found to be extremely badly worn, and a new set were machined, and then refitted and alignment of motion checked and several adjustments made to the coupling and connecting rods. A complete set of new connecting and coupling rod brasses have been produced, as the originals were almost worn through to the wedge blocks, and are awaiting final fitting.

New Rod Bearing brasses have been manufactured and machined and almost all have now been final fitted, the remaining rod bearings are currently being completed.

SIDE TANKS

As the loco had been stood derelict out in the open for many years, the outer steel platework has suffered quite badly, as so there was little option but to construct a new pair of side tanks from scratch, utilising the originals as patterns. The original cast filler caps and surrounds were re-used.

SMOKEBOX

Again, this was another victim to standing in the open for many years, and was found to be unusable. So a new smokebox has been rolled and the front plate has been made and i awaiting fitting in due course. The smokebox door fitted to the locomotive was a replacement one presumably fitted by the previous owners, and is flat not dished.as was fitted to the original locos. So  again a pattern was made and a new dished door has been manufactured, along with the correct locking wheel made. The smokebox is awaiting completion so it can be fitted to the boiler.

SPRINGING GEAR

On examining the locomotive it was found that the springing arrangement had been modified heavily from the original design. In an effort to return the locomotive to original condition new spring hangar's and spring compensation beams have been made to the original specification, with some slight modifications  to improve the working of the compensation.

The old springs were badly corroded and were sent off to a spring manufacturer to be renovated, and returned  having had all the spring leaf's replaced, leaving the original buckles as the remaining original part of the springs.

The springing gear has pushrods that go through tubes on the well tank to bear on the top of the axlebox, and so the renovation of the well tank required new tubes to be manufactured and fitted.

WHEELS

On examination the tyres fitted were found to be badly worn, and  a new set of six rolled steel  blanks was obtained and machined the correct profile.  The old tyres were cut off, and the new ones heated up and fitted. The centre set being flangeless, as the originals,  to allow the locomotive to negotiate track with smaller radius curves . In addition the crankpins were replaced as again they were worn beyond acceptable limits, so the opportunity to bring them back to original dimensions was taken.