The Supervision and Administration of Locomotive Repair Contracts

I started a thread on this subject in the Steam Traction section. In case anyone is interested, here is a summary of the work done to date on an austerity, Bagnall 2746 The Duke. It was prepared in advance of a visit from ORR and was intended as a guide to the compliance paperwork, it isn't enough to prove compliance in itself. If anyone is planning an overhaul of a run -down locomotive of similar size it may just be useful as a guide to the possible pitfalls and work required. We aren't finished yet, but we are getting close.

BAGNALL AUSTERITY CLASS 0-6-0ST No.2746 of 1944, “THE DUKE”

The project is independently insured for accident/injury; policy suspended until the boiler comes back and we can resume work.

SCHEME OF WORK

Aim: to conduct a thorough mechanical overhaul to fit the locomotive for regular service, and a fundamental repair of the boiler, with appropriate materials, to a proper standard, by qualified and experienced persons where appropriate and with assistance from others.

Personnel: We have the full support of the team of 48624 Locomotive Limited, who restored that locomotive to a very high standard, demonstrated by ten years in reliable regular service. The principal members of that team are:

AG - commenced apprenticeship at Derby Works in 1947. National Service: corporal in charge, Longmoor Running Shed, Longmoor Military Railway. Returned to British railways. Shedmaster, Annesley. Shedmaster, Great Central Railway, 1974 to 2017, latterly as semi-retired consultant. Advises on mechanical maintenance standards and general technique, boiler maintenance issues and the selection of appropriate competent contractors.

SH: machinist and fitter: completed 5 year engineering apprenticeship. NVQ level 3 BTec engineering. City& Guilds CNC programming + City & Guilds part II

MC: machinist and fitter: Craft apprenticeship, AMEME hons. City & Guilds, craft certificate.

JK: welder, boilermaker, Mechanical and Electrical apprenticeship, 4 years – craft engineering, drawing and development, fabrication engineering craft practice and related subjects. NVQ level 3 Engineering Maintenance.

The function of other volunteers is to fetch, dismantle, carry, clean, paint and perform similar tasks in support of the skilled members of the team.


Contractors and Suppliers

Boiler Contractors: Locomotive Maintenance Services. 14 Bakewell Rd Loughborough LE11 5QY.

Boiler Sub-Contractors: Newtons of Cromford.

Jones Brothers of Darlaston 0121 5687575, locomotive spring manufacture and repair

HP Rings of Chesterfield 01246 261299, cast iron piston ring manufacturers

Armstrong Oilers, NYMR, lubrication felt pad manufacturers

Spiralweld of Southampton 023 80228801 metal spraying and turning.

Wiilam Twiggs of Matlock, steel stockholders, suppliers of engineering steel and engineers supplies

Leeds Bronze: non ferrous supplies. 0113 2718711.

D & J Hawkins (Casting Services) Chesterfield, 01246 862097, non ferrous castings & stock supplied to order in LG4 bronze, pattern manufacturers.

Ribble Steam Railway (Russell Walker) pattern making contacts, castings in SG iron organised, locomotive fittings supplied.

Great Central Railway, Loughborough: whitemetalling and larger size machining services.

Heritage Traction Supplies (Martyn Ashworth). Fittings supplied.

Miniature Pressure Gauge Company: steam pressure gauge suppliers.

Railway Wheelset and Brake Ltd: vacuum & steam pipe suppliers.

Columbia Metals of Halifax: suppliers of HP steam grade C106 alloy copper pipe.

Bill Shorthouse Metals 01299 401648 silver solder supplier.

Boiler Work.

After various inspections we were advised by David Wright of LMS that a radical approach was required, dubious boiler components to be replaced with new material rather than repaired and the aim is to make all components fit for long term service. He has been instructed to proceed. Work is in progress; the boiler compliance file is at LMS for consultation by the boiler inspector on periodic visits. Preparation and dismantling including stay and firebox tubeplate removal carried out by MC and JK. The LMS invoices are available for inspection.

The programme includes: re-making and refurbishment of all components as necessary. Work identified includes: New smokebox and ashpan: to be fabricated by LMS (ashpan completed 11/19). New chimney pattern with casting in SG iron produced in joint venture with Ribble Steam Railway, new Hunslet pattern blastpipe casting obtained through RSR from Bo’ness & Kinneil Rly. Both to be machined by LMS and collected by them 28/11/2018. Despite initial repairs to smokebox tubeplate it has been condemned and a new tubeplate has been made; fitted 1/21. Weld repairs to base of barrel under the dome. J pipe removed for manufacture of new regulator link and machining of valve surface by LMS, J pipe casting examined and confirmed fit to re-use. Broken regulator quadrant repaired with brass insert, regulator rod welded up and turned down to proper size, regulator gland bushed to match.

Replacement of all longitudinal stays will be undertaken, new stays machined and ready to fit. Lower throatplate: cracked, saucer corrosion around stay ends, new lower part of throatplate to be welded into place (done) copper tubeplate condemned as beyond repair due to over-rolling (oversize tube holes and crown forced up, full thickness crack top flange) to be extracted (done) new copper tube plate to be formed and machined (done; new tubeplate now fully machined and fixed with rivets and set screws). Crown stays wasted to bullet points, some snapped entirely. Palm stays and stay slings removed. New palm stays made and fitted, stay slings refurbished ready for possible re-use. Sling stay support girder removed for examination, stay pin holes nicked in earlier (possibly NCB) repairs, to be welded up and re-drilled (done and girder rivetted back into place). All crown stays removed. Crown examined for cracks around stay holes, cracks found were ground out and welded up, newly drilled holes tapped to original size; sling stay holes especially bad due to old cracked gas welding repairs. Full set of new plain Crown stays fitted – October 2019; fitting of sling stays completed: December 2020. Inner crown plate distortion caused by over-rolling removed by heating and jacking against former. Lower firebox sides condemned due to foundation ring grooving and saucer corrosion around stay heads – cut out, stays removed, new plate to be welded in (done). Manufacture and fitting of lower side stays completed March 2019.

Backhead condemned due to extensive deep cracking: rear corners from foundation ring to crown, plus cracks up each outer column of backhead trays, crack between clack holes, triple crack between stays etc etc. Old backhead cut off. New backhead formed by Newtons, delivered 28/11/18, trimmed and machined to make ready to fit. Closer pieces made and rivetted to the new backhead and welded to and forming part of firebox outer shell. New Firehole door ring made and machined and fitted. Complete new set of backhead stays machined, fitted and tooled over. Bosses for pipe fittings flatted to true surface; backhead complete as of 27/6/2020. Dome joint flatted. Foundation ring condemned on inspection: triple cracks at each rear corner. New ring formed in one piece by water jet cutting from slab, machined and fitted in place to be rivetted in place sides and rear rivetted by 4/7/2020. Broken upper side stays identified by NDT and direct examination – replaced. Boiler barrel and upper firebox is generally very close to original manufactured thickness. Localised corrosion in base of barrel under the dome repaired by welding. Copper main internal steam pipe to be annealed, new external steam delivery pipe to be made; arsenical copper pipe in stock. Cracks found in internal injector delivery pipes and blower pipes; replacements made by LMS, machined and fitted 1/21.

New bosses for washout plugs fitted, tapped, new plugs fitted.

New regulator pin made, valve face skimmed flat. Regulator j pipe casting examined and passed fit for service. A set of new firebars has been purchased from LMS; the firegrate carriers are made and ready to fit.

Boiler Cladding

All cladding sheets and dome cover have been cleaned to bare metal, painted with Aluminium paint on the inside and red oxide outside. Crinolines: missing, new set made. Drawing provided by LMS. 40mm x 6mm steel strip supplied by Twiggs. Insulation to be purchased. Lagging bands required.

Mechanical Overhaul

Frames: had been conserved with car body underseal wax. No significant corrosion. Cleaned down and painted inside and out.

Drawgear: Taken down for examination by AG. Front couplings: satisfactory. Rear Couplings: hole in bufferbeam worn out of square, shank of hook found to be packed with miscellaneous items including possibly needles from a needle gun. Hole filed square, shank built up with weld by JK and ground square. To check: safety cotters re-fitted?

Buffer beam gusset plates not subject to distortion; mechanical audit confirms frames are square. Steam heat and vacuum pipes taken down and rebuilt by MC . New sh + v hoses purchased from Railway Wheelset and Brake. New steam heat hose fittings required – originals missing. Second hand items obtained from Colin Fearnley and reconditioned by SH and MC.

Wheels & Axleboxes: flanges examined by AG, 10/9/11. Flange profile: no measurable wear against London Midland Region tyre profile and flange root gauge, profile A on leading and trailing wheels, profile G on centre driving wheels. Tyre thickness, 2” on leading and driving wheels. Trailing wheels: 1 15/16” L, 2 1/16” R. Fit for service. No loose tyres. No turning required. Journals checked by micrometer for cylindricity, crown bearings checked for fit with engineering blue and scraped in as necessary. Wheels de-greased cleaned down and painted. New felt lubrication pads purchased from Armstrong Oilers, NYMR, to spec 2149B. One broken axle box top pin replaced in EN24T (LH rear). Bronze wear plates fitted to centre axleboxes to reduce side play and secured with 3/8 brass CSK machine screws. Loco frames to be periodically rolled with Atlas pole and axleboxes topped up.

Springs & brake hangers & brake gear: some broken leaves found. All springs despatched to Jones Bros Darlaston for repair/overhaul and 2 new springs ordered. Spring hanger pins and brake pins found to be “necked” and corresponding holes in frames, spring links and brake hangers worn oval, in some cases obviously no attention since 1944! Holes reamed out with ratchet drill and journeyman and bushed with new bushes, steel grade EN24 (hard wearing). New pins made, EN8, (tough and resilient). Brake blocks found to be unsatisfactory ex – diesel shunter items. New set purchased from LMS, machined and fitted. RH leading block requires adjustment (done). Extensions (steel, ½”BSP) fitted to spring link lubrication cups for ease of oiling. Brake shaft: worn on RHS drivers side due to action of brake cylinder. Shaft taken down, journal polished to acceptable roundness and cylindricity, steel bush made and fitted, re-assembled. Main brake adjusters seized solid. Freed off by heat, threads inspected cleaned and greased, all threads on all brake components freed and greased. Nuts turned freely by hand when refitted.

Sanding Gear: sandboxes full of wet concreting aggregate and discharge paddles rusted solid. All boxes cleaned out, paddles dismantled, cleaned up, greased. Operating links; jammed solid on vacuum pipe but incomplete. Had obviously not worked in a long time. Remade and freed off, new drivers operating handle and shaft installed in cab.

Cylinder Block, Valves and Pistons: No significant top corrosion on cylinder block. Top cleaned down, 3 coats aluminium paint, filled with moulding sand, new smokebox floor plate sealed down with new studs and high temperature sealant. Bores checked by micrometer, minor wear at the ends but AG advises fit for ten years work. Bores wire brushed and greased, new rings ordered from HP Rings to 18.067” and fitted. Piston rods have been chromed in the past and are in good condition. New metallic packings cast from bearing grade whitemetal (swarf from slipper blocks, see later) and fitted. New cylinder cover gaskets made from gasket material supplied by LMS. Valve faces and valve plates: good. Valve rods: corroded and very rough, suspected failure of lubrication. Cylinder lubrication atomiser found to be non-conforming, fitted with extra and jammed non-return valve, effectively preventing all lubrication; rectified. Valve rods sent to: Spiralweld of Southampton for metal spraying and machining back to true. Atomiser re-made by SH. New bronze bushes made for valve rod glands and rod tails, - bronze source: Leeds Bronze.

Motion and Valve Gear

Reversing lever and rod taken down, lever pin found to be worn. New pin made, re-assembled. One eccentric has been broken in the past and expertly repaired by letting in a steel plate. AG pronounces satisfactory, spare purchased from Heritage Traction Supplies just in case. Connecting rods checked; big and little end bearings found to be an excessively loose fit. New big end castings purchased from LMS, connecting rods sent to GCR Loughborough for machining and whitemetalling. Slipper blocks sent to GCR for Whitemetalling, machined to size on return, whitemetal swarf used to cast metallic piston packings. Slidebars checked against cylinder centres with piano wire and electric micrometer. Variance reduced to 0.008”. Piston cotters had worn and are oversize compared with drawing. New cotters made. Side rods a good firm fit on crankpins. Rods and motion re-assembled. New lubrication trimmings made and fitted throughout, valve rod lubrication improved with extra trimmings. Motion and valve gear re-assembled, valve travel checked by manually propelling frames under supervision of AG.

Saddletank

Sound but contained large quantity of scale, tank filters choked, water level test cocks missing internal baffles thin but serviceable. Work done: Filters removed. Access holes cut in cab end of tank. Scale raked, vacuumed and flushed until tank clean inside. Outside being cleaned down and painted. Access holes welded up again, try-cocks being re-instated using modified Shanks brass cistern fittings. Possible future use of epoxy paint to seal tank bottom against future corrosion.

Cab, Bunker and Boiler Fittings.

Bunker condemned, new bunker fabricated and delivered by LMS. Fitted with ½” Whitworth bolts on top of existing footplating. Slot cut, bent down and welded so nothing for a shovel to catch upon. Coal rails fitted. Cab sides bolted into place, trial assembly of cab roof. Rear windows glazed with polyacetate, new catches and hinge pins made. Front windows: laminated glass supplied by Buxton Glass Feb 2019.

Combination ejector and brake valve: badly worn internally, parts which should have had clearance of 0.005” had clearance of 0.050”; replacement components made in bronze type SAE 660 obtained from Leeds Bronze (certificate on file).

Clack valves: in a poor state, valve seats replaced with unsuitable PTFE cones; on one, valve seat had been carelessly removed, female thread damaged presumably by a chisel, signs of blowing through and steam cutting. Valves condemned: not enough metal left to re-machine. New valves made, with stainless steel seats, by LMS at Loughborough.

Displacement Lubricator: 2 feed wakefield pattern handed over by previous user. Not from this locomotive and frost damaged. Unused, new gunmetal displacement lubricator purchased from Martyn Ashworth.

Injectors: taken down examined passed fit by AG and SH and replaced on locomotive. Securing nuts to be welded for security.

Safety Valves: springs corroded, one casing frost damaged, one valve seat steam cut and obviously has been blowing through. Casing purchased from Ribble Steam Rly as rough casting, casing and new base and spindle machined by SH from LG4 bronze supplied by D & J Hawkins, material certificate on owners file. New springs on stock at LMS from Tested Spring Co. Valves delivered to LMS for testing as part of boiler testing. The overhaul procedure and specifications for Ross pop safety valves in MT276 to be strictly complied with and forms G and H to be completed and held on file as per HRA boiler safety recommendations. Holes for safety valve mounting bolts welded uo, to be re-trilled and tapped. Safety valve pedestals ground flat for metal to metal seal.

Whistle: cut off by previous user. Replacement used Hunslet pattern with valve purchased from collector.

Manifold: Unsatisfactory, porous casting rectified in the past by brazing. New casting ordered from LMS. Gunmetal casting fettled and machined; ready to fit.

Boiler Gauge Glass Cocks: worn beyond repair. New set ordered from LMS; machined and ready to fit.

Clack feed etc pipes, to be gone through as necessary; some believed to have been stolen in 2011. LG4 castings in stock machined to make flanges (D & J Hawkins certificate on file). Revised feed to ejector to be taken from clacks rather than manifold. Take off fitting to be supplied by LMS. Low pressure water feed pipes suppled from stock by 48624. 10 gauge HP copper pipes supplied by Columbia Metals of Halifax. Certificate to follow. Silver Solder spec Ag155 supplied by Bill Shorthouse.

Gauges: new 300psi 6” steam gauge and 120psi steam heat gauge purchased from Miniature Pressure Gauge Company, test certificates stored with gauges. Duplex vacuum gauge being overhauled. Wooden mounting board fitted in cab.