Christmas 2019

A Productive Season

Updated 5th January

Having missed the previous working party, Paul was keen to make amends and was first to start work on 22nd December. With the Santa Special trains running, there were five loco cleaners looking for an afternoon job so Paul set them up in a production line to dismantle and clean all the auxiliary steam valves. Many of these are mounted on the manifold (the Chinese call it a 'steam pagoda') to control the flow of steam to the blower, whistle, injectors, turbogenerator, etc. Others are found downstream of the injectors, as clack shutoffs and for functions like the slacker pipe and ashpan drench. From Dahuichang we had acquired a spare, unused steam manifold with most of its valves, and also some additional spare valves of unknown provenance. In total we had 25 valves to deal with, of several different styles and sizes. They varied in condition from brand new to completely scrap; fortunately we have more than we need!

Having demonstrated the dismantling and cleaning of one valve, Paul set up the production line. Matt dismantled each valve, and put all the parts in a tray to keep them together. Neil then used a wire wheel to remove rust and dirt from each part, before they were cleaned with solvent degreaser and dried by Dan. Two parts of each valve needed painting: the handle and the gland nut. These were further cleaned by Dan's brother (sorry, I've forgotten your name!) with white spirit, and dried. Sarah then stamped identification numbers into those parts, matching the numbers tagged in each tray of bits, and painted them in primer. With 5 people on the job we made rapid progress and completed more than half of the task. The following day there were fewer people around, but Paul and Matt continued working on the valves.

On Christmas Eve, we lost Matt but gained Dave. Dave has been making excellent progress on a set of CAD drawings for the boiler, and conducted an informal design review with Paul. It was very helpful to do this with our existing boiler in front of us. Another great help was the new boiler currently being built at Boston Lodge for 'James Spooner'. This has many constructional features similar to those on the C2 boiler, and it was good to see how those have been implemented on a design that is compliant with the UK and EU boiler regulations.

Paul and Dave then went back to the steam valves. In the cold weather, the paint takes a long time to dry so they took the opportunity to add another coat of paint to the parts that needed it. Matt had enjoyed the days before Christmas so much that he returned on 27th to finish the job off. Tom and Will also tackled another part of this job, cleaning up the steam manifold.

Both Daves and Andrew focused on reaming the holes for the motion brackets, followed by those for the brake hanger brackets. The reaming process was quite lengthy as there was limited access to the holes and we had to use a hand-worked rachet drill to turn the reamer. It was possible to achieve good alignment by using the hole in the opposite frame plate as a guide. The reamed holes proved to be an excellent fit for our new fitted bolts (as planned!) and these were then inserted and torqued up.

While that team worked on reaming, Erle had arrived and set to work on his project with the lubricators. He had made some new springs to replace those in the ratchet mechanism; quite an ingenious process after a bit of trial and error. It is amazing quite how many parts there are to overhaul on a steam locomotive, and even a tiny spring like this could cause a major failure.

Erle then set up one of the lubricators for testing of the pumps. This demonstrated that most worked fine, but a couple were sub-standard and did not provide enough pressure to overcome the non-return valves. It turned out that these had a fraction more clearance between the piston and body, so they will be swapped out for better examples.

Erle has also been progressing with a number of other jobs on the lubricators, including fitting sight glasses and painting parts of the third (spare) lubricator assembly.

On the 28th, some of us took a day off to enjoy the annual 'cold turkey' social event which brings together staff and volunteers from many of the Welsh steam railways. Traditionally this is held on the Ff&WHR, the Welshpool & Llanfair Light Railway or the Tal-y-Llyn railway, but this year the Llangollen railway offered to host it and they put on an excellent event with a well-stocked bar and a variety of hot food. Traction was provided in the form of 'Foxcote Manor' and we had an excellent day. Thanks to the Llangollen Railway for their hospitality - why not go and visit them yourself in 2020?

With all 24 fitted bolts in place in the brake hanger brackets, the nuts and bolt heads were primed and then painted. Will assisted both Daves with this task. Then came suspension reassembly. The rear springs are quite easy to fit, being held in with a threaded yoke through the frames. The front springs were a bit more difficult, having to be preloaded with boiler clamps, as described in our previous working party report. But all went together without too much trouble, and, after removal of the packing beneath the frames, the locomotive was mobile once again.

Next task was to fit the cylinders. Firstly, insulation was fitted into the cavity behind each cylinder, to prevent heat from the cylinders damaging the rubber drawgear mounted between the frames close by. Then the cylinder spacer plates were hung loosely on bolts through a couple of the holes in the frames. The locomotive chassis was moved under the A-frame crane in the shed, and the crane used to lift the first cylinder into position. Andrew turned up some tapered dowels which fitted through the bolt holes to align the existing holes in the frames and cylinder as precisely as possible. Using a hydraulic jack, the cylinder position was adjusted such that the dowels fitted well. A little prodding with a screwdriver blade adjusted the position of the packing plate, so that the holes in it also aligned with the bolt holes. Normal bolts were then used to clamp the cylinder firmly in position, and the process repeated for the cylinder on the opposite side.

As with the motion brackets, a ratchet drill was used to drive the reamer through the holes in the frames and cylinders, using the opposite holes to provide alignment. This worked for quite a number of the bolt positions, and after about a day of work, Andrew, the two Daves and Tim had reamed about half the cylinder bolt holes, and the corresponding fitted bolts were in place. There are a total of 32 holes, each 1" in diameter, which is quite a lot of reaming!

The bottom row of bolts along each cylinder had good access from between the frames, but the ratchet drill operator needed to be below the locomotive in order to carry out the reaming operation. The easiest way to achieve this was to put the locomotive over a pit. A shunt was carried out on 31st December, to put the tender chassis at the back of the C2 Shed and the locomotive chassis at the front, in readiness for a move to the pit on 14-road. Members of the Waggon Tracks Project, who had been overhauling slate wagons over the previous week, assisted us in this. Paul 2 drove the diesel shunter to carefully move the locomotive frames, while Dan, Emma, Dave 2 and Tim moved the tender chassis by hand.

The New Year celebrations in Porthmadog were not too leery this year, which meant that a good number of people were back in the works by 10 am on 1st of January, eager to carry on the work. Dave 1 used the diesel shunter to move the locomotive chassis from the C2 Shed to 14-road. Andrew, Olly, Tim and Dave 2 then took turns on the ratchet drill to ream the bottom row of bolts along each cylinder. As before, the holes were reamed in pairs, one each side, the holes cleaned and the fitted bolts driven into place. Because the holes in the frames and cylinders had been well aligned, the work was not too difficult, but it was time consuming, and it took much of the day to ream the holes and fit the 10 bolts under the cylinders. At the end of the day, Andrew used the diesel shunter to shunt the locomotive chassis back into the C2 Shed.

The remaining 4 pairs of holes were more difficult to deal with. The front drawgear is mounted between the cylinders, and blocked access to some of the holes. So it was time to disassemble the front drawgear. It's quite a few years since we assembled the drawgear, and we had to look at Andrew's drawings of the assembly procedure to remind ourselves how it all comes apart. With our memories refreshed, the drawgear was disassembled, and two more pairs of holes could be reamed and the corresponding fitted bolts fitted.

One pair of holes on the rear of the cylinders could not be accessed from between the frames, due to web plates which form part of the dragbox. So these holes had to be reamed from the outside. Dave 2 found that a 25 mm hand reamer could be driven through the holes without too much fuss; unsurprising since the holes were already nominally 25 mm indiameter. This them allowed us to set the alignment of a jig which Andrew made, and which clamped to the cylinders. This then gave us something to react the ratchet drill, which we could then use to drive the 1" reamer through. Another two holes reamed and fitted bolts in! Just two holes to go.

We had left the two most difficult holes until last. They are up under the frame top plate, inside the dragbox, with web plates blocking access from the inside and the cylinders blocking access from the outside. Consideration was given to using normal bolts in this position, but we were not to be defeated that easily. Although there was not enough space, inside or out, to get a ratchet drill onto the end of the reamer, there was space to align the reamer itself, and just enough to get a standard socket and ratchet drive onto the square end of a hand reamer. It was found possible to use a bar of wood to apply force to the back of the ratchet, and with some contortion by the ratchet operator, the arrangement could be used to clean the holes with the 25 mm reamer. Next was a 1" taper hand reamer, which could be started in the 25 mm hole and opened the inner end of the hole out to 1". Another 1" hand reamer with less of a taper was then used, firstly from the inside, and then from the outside (using a long chain of socket extension rods to drive it through the gap between the cylinder and valve). Finally, little bit of work with some emery cloth made it possible to tap the fitted bolts into position with a mallet. Job done!

To provide corrosion protection, the bolt heads and nuts were cleaned with white spirit and then primed. Also primed were edges of the frames where the ratchet handle had chipped the paint off. It is unfortunate that, because access is often difficult, paint will inevitably get chipped while carrying out work, no matter how hard we try to avoid it.

We had not painted the nuts on the leading brake hangers and the motion brackets, as we knew we would be working close to them while fitting the cylinders. Now that it was time to paint them, it was realised that the brake hangers fitted to the motion brackets probably wanted to be painted the same colour as the motion brackets; red not black. The motion brackets had been primed using black primer, but red paint gives the best result when applied over a grey undercoat. So to provide protection to the whole assembly, the grey undercoat was dug out of our paint store, and Andrew and Dave 1 painted the motion brackets (and associated brake hanger brackets) in it. This has transformed the appearance of the chassis.

Final tasks are to paint black top coat over the primed parts inside the front dragbox, reassemble the front drawgear, then finish paining primed parts around the front end. Andrew and the two Daves stayed until the weekend after New Year to complete this work.

Dave 1 also carried out some measurements on the boiler to support our specification for the new one; Huw and Gwion helped out with this.

We must also mention that during the Christmas period several of our group members helped to keep the railway running, as is often the case. Paul took on the role of site supervisor and standby driver for several days, and Jon acted as a roving fitter. Sam and Alan both drove some trains on the FR.

As I write this update, the working party is just about coming to an end and we have achieved a major milestone with the cylinders and motion brackets permanently fitted. Our next working party is booked to start in just a week's time, but after the big Christmas push we're going to make that a 'homework' weekend when we will each work on drawings and design work rather than on the loco itself. Paul has already been making progress on tasks including design of piston rings, drawings for steam valve spindles, and cab support bracket specifications. We'll be back at Boston Lodge at the end of January - see the 'Working Parties' link on the left hand side menu for details of our 2020 dates.