Sunday, 19 February 2017

Maintenance Update (gadget, injector, felt, bracket)

Wednesday 15th
John T began the day by gluing insulation around the cylinder blocks. There are two layers, here, held in place temporarily using spray-on glue. John G and Gilbert subsequently assisted John T to get the cladding pieces fitted back on over the insulation. It looks easy enough, but lining up the bolt holes and persuading the bolts to go in straight is a challenge. Particularly fun are the bolts underneath! Gil (on his new pills) volunteered to crawl under the cylinders and fit those! After the large piece that wraps round the cylinder block, there are several small pieces to cover each end.

Gil fitted the timing gadget onto the two cylinder valves in readiness for David to play with the timing. I have a horrible suspicion that that involves pushing the loco up & down a bit! As the valve moves, a needle attached to the end of the valve rod slides two sleeves apart, thus marking the end positions of travel. I’m intrigued as to what happens then!

Bruce refitted the insides of the two injectors. A generous wrapping of PTFE is necessary round the end covers otherwise these tend to leak during use. It is critical to have two working injectors because of having to guarantee to maintain a sufficient water level in the boiler. If there was only one and it failed, you would be in deep do-dos.

Bruce & Gil examined the options and sizes for making a bracket to support the brake column. Amazingly, they couldn’t find a suitable bit of metal from which to construct the bracket.

As the weather forecast was dry in the morning and rain arriving at lunchtime, I began needle-gunning chairs, trying to build up stocks of boot scrapers for the beginning of the season. I managed five before rain did stop play. John G applied a top coat to the 6 in the production line after lunch, snugly tucked away in the warmth of the van!

After lunch I fitted the Mason’s Valve back in the cab (with assistance from Bruce); connected up the condensing coil, and then cleaned the sight glasses in the hydrostatic lubricator.

I was tempted to set you a quiz: How many of these components in the cab do you know? No prizes
for getting them all right.

Saturday 18th
On Friday I had an order for a boot scraper, so it was my first job to complete the lettering; fit
brushes and box up. After tea break, I spent the entire day inside the firebox.

Most of the stays are copper and are riveted over. Some are monel metal, which is a nickel alloy that is resistant to corrosion. These have nuts on the end. Those nuts that are in the fire bed, or close to it, can burn away in the intense heat. My job today was to clean these nuts by wire brush and then apply a heat-resistant (to 750°) paint.

The grate was not very clean of ash & clinker; the sides were covered in sooty deposits, and it is a tad cramped in there, especially down at the front end.

Gilbert started to fit one of the running boards and discovered how awkward (and heavy) they are!
Paul G [Loco dept] gave him a hand. Paul’s reward was two chocky biscuits plus a cup of tea.

John T finished fitting insulation around the cylinder blocks and refitted smaller cladding pieces.
Only the valve covers remain to be tackled - when the timing measurements are completed. John
then moved on to the brake column. He hoovered out the bottom of the box area and refitted the
top plate.

Gilbert subsequently got in John’s way, and then Bruce’s way; but he did fetch me a 100V lamp so that I could see what I was doing inside the firebox!

Gil, John and Bruce all had a play with the handbrake column, trying to work out how best to gain access to weld on a securing bracket. There are three metal discs and a bearing in the middle. The centre disc is the one to which we intend to weld the bracket. It would be nice if we could take it apart, but the handle is secured with a tapered pin which doesn’t look as though it wants to come out!

At the very least, it now needs some new nuts & bolts to hold them together!

Bruce spent much of the day making new felts for the piston rod lubricators.

He found a tin of almost the exact same diameter as the rods, which makes it handy for cutting out felt. The top felts have curved lower surfaces to fit round the rods. They are held in position by a metal cover.

The lower felt is just a strip that fits inside the bottom part. Here you can see the felts sitting in oil over lunchtime ready for fitting in the afternoon. As you can see, Bruce made two new top felts and only one for the bottom.

We didn’t get as much done as we had hoped, but every little bit is progress. We have to be available for service in 12 days time … that’s only three working days for the team.


Sunday, 12 February 2017

Maintenance Update (cylinder, chain, shaft, pin)

Wednesday 8th
Having been put on a new type of pill, Gilbert was back to his normal self, and was joining in everything again. However, he couldn’t get inside the cylinder to measure the internal bore, so John T did that. It appears that the cylinders have worn differently on each side - something that is not easily explained immediately.

Brian (with assistance from Gil) worked on the cylinder covers, starting with taking the RHS cover off (otherwise how could John climb inside?). All of the studs were cleaned and dies run down them; all of the nuts had a tap run through them. John T worked on the RHS, while Brian fitted PTFE seals to the two covers. At the very end of play, Gil, Brian, John and I fitted the cylinder covers back on. Gil manned the pulley; Brian applied the brawn. Alex gave encouragement.

John G was wielding his paintbrush once more. Beginning with the proverbial black bottoms (of the rail chairs that were cleaned last time) he moved on to applying a coat to the inside of the cylinder cladding.

The outside will get a coat later, as it is planned to repaint the black running boards and anything nearby. Hence the step that also holds the vacuum pump got a coating from John, too. Apparently it had been noticed (during the mechanical inspection by GWSR) that a rivet was loose. David fixed that so John painted it!

John T had completed the components of the gadget that he designed for guiding the loco/tender links into their correct holes. David welded it all together, even manufacturing a handle from a length of fencing that he found in the skip. Needless to say, John G painted it. Here it is standing upright inside our container.

Bruce had brought some chain from home. Two lengths of chain had suffered at the hands of footplate crews: there is a chain retaining a pin inside the smokebox which is used to secure the bar that is behind the smokebox door and into which the dart slots when closing the door; there are chains on the lids of the sandboxes, too, one of which had given up the ghost. So, David cut, fitted and welded new chain into place.

Bruce lapped the clack valves internal to the two injectors, so these are all ready to be reassembled and fitted.

John P [Loco Dept - performing mechanical checks] spotted that the brake column on the tender is not as secure as it might be. Bruce removed the cover plate and peering down, it became obvious that there are only two bolts holding the flange at the bottom of the column. There is no room for any more bolts down there! However, other tenders have got a bracket towards the top of the column, which holds it steady. John P said that the column could fracture and hence we should manufacture a retaining bracket.

Bruce’s homework this week is to ream the taper in the rocking shaft such that the new pin is a perfect fit.

Brian helped Bruce lift it into his car; I followed Bruce home and gave a hand lifting it out again.

Friday 10th
Bruce reported: “I have finished fitting the offset pin into the rock shaft. It was quite a long winded job as the removal of small amounts of metal from the diameter has a much greater effect on the amount the pin goes into the taper.”

Saturday 11th
Loco Dept wanted to fit new brake blocks to the loco, which meant being over a pit to undo the mechanism that connects all brakes together (so that individual ones can be removed and replaced). This meant coupling loco and tender … which meant an opportunity to test the connection jig that John T (in particular) designed. It did work, but some instructions will be necessary for those who are not familiar with it.

When the team from Loco Dept got to work and removed the old brake blocks, they discovered that the new ones wouldn’t fit! They are too wide at the pivot point, so a small amount needs to be machined off each one. So, the loco was pushed back into the shed.

A few minor tasks were carried out, such as: painting rail chairs, cleaning up the outside of the cylinder block, locating and acquiring some insulation to replace that between blocks and cladding.

However, the Big Task of the day took the whole team plus helpers from Loco Dept: this was replacing the LHS rocking shaft and connecting up the valve.

For a start, the rocking shaft is a two-man lift. Getting it up onto the running board was no mean feat. Bruce cleaned up and smeared oil on the brass shells. These two shells do not sit horizontally; they incline at perhaps 60°. The outer arm of the rocking shaft (black) has to pass down through a slot in the running board. Then the shells had to be clasped around the shaft (using Bruce’s fingers) while two chaps used a bar through the centre to manoeuvre the whole thing down into its saddle.

The top cover went on and was bolted down. At this point, Bruce rocked the whole thing to-and-fro to make certain that it was not too tight! With the oil pot fitted back on the top, this stage was complete.

The next step was to fit the valve link between the rocking shaft (outer black arm) and the valve spindle crosshead. That’s not too difficult apart from the fact that the taper pin is in the rocking shaft end, meaning that the link has to be rotated sufficient to get the pin into its hole.

Meanwhile, at the other end, the valve spindle crosshead was refitted and connected up to the valve spindle. Needless to say, the valve (and hence the crosshead) had to be pushed forwards before the link would engage with the crosshead. That done, the outside motion was complete.

Back inside the frames, the rocking shaft arm (red) needed to be connected to the intermediate valve rod that joins the rocking shaft to the die block in the expansion link. So, I volunteered to go in the frames this time; John T manned the reverser in the cab, and someone on the outside pushed the valve further forwards, sufficient for the rod and the arm to mate. Phew!

If you look it up in The Engine Driver’s Manual or the BR “Black Book” you find this diagram:


Sunday, 5 February 2017

Maintenance Update (bonnet, cladding, gauges, bore)

Tuesday 31st
Bruce’s homework for today was to take the tapered reamer to JB Toolgrinders Ltd at Tewkesbury for sharpening. We need it doing fairly urgently so that we can finish and refit the rocking shaft.

Wednesday 1st Feb
Bruce was up on top of the boiler again. Having machined the clack valves, Bruce refitted them. He is well pleased at how they remained steam tight after the previous machining, a couple of years back. Here he is fitting the brass bonnet back over the clacks.

He also measured the new pin for the rocking shaft and checked the dimensions of the taper within the rocking arm. The tapers must match exactly.

John T continued with the gadget for lining up the three drag links. This is very much a trial and error exercise. Having fitted the links back into the tender, the centre one is higher than we expected, which means another mod to the gadget’s design!

John G began by painting a couple of rail chairs and then intended touching up paintwork on the cab. However, there was so much condensation, that all he could do was clean and prepare the surfaces.

Brian began by refitting the two eccentric rods between the frames.

John then assisted Brian in removing the LHS front cylinder cover. This is so that we can check the internal condition for wear. To get the cylinder cover off means removing the cylinder cladding … which necessitates removing the rear section of cladding, too!

Luckily, it didn’t mean removing the valve cladding because that means having to remove the valve rod lubricator … Did Churchward ever work in the loco department, or just in the design shop???

You may spot that the piston head was right at the front of the cylinder, which meant you can’t measure the internal dimensions or check for wear! So, Brian found a pinch-bar; I found a length of wood, and together we pushed the loco backwards a couple of feet. It all looks very smart inside there (fortunately!).

John & Brian cleaned up the faces of the cylinder and its cover.

The gleaming gauges are another example of John’s handiwork with the polish.

Fitting these back on was a task allocated to me by the supervisor (Gilbert). Apart from that, I continued where John left off, painting rail chairs.

I had been advised that for the Wartime Weekend, there will be 2,000 campers in the field at Todders, so I should build up stocks of boot scrapers! Also, there is to be a Spitfire in the car park and for a fee you might get a chance to sit in it - but you have to pre-book. So, reserve April 22nd/23rd …

Saturday 4th
The sun shone (which meant I could work outside) so I prepared six rail chairs for boot scrapers. I also painted the gold lettering on those in the production line.

John T was busy: He began by measuring the cylinder bore on the LHS (under the supervision of Gilbert, who was in some pain during the day). John then checked the piston head diameters, and discovered that there has been no appreciable wear since last measured. John assisted Bruce in removing the cladding from around the RHS cylinder with a view to that cover being removed for inspection. The block & tackle was moved across and attached to the cylinder cover, but the decision was taken to leave it for Wednesday.

Bruce played with the new pin and the rocking shaft, ensuring that the parallel section of the pin is parallel and ditto the hole in the rocking shaft arm, which Bruce had to ream out a little. He can’t finish the pin/arm fit because the tapered reamer is away for sharpening. Bruce then cleaned up the injector innards ready to be fitted back in their bodies.

Pete [Loco Dept] replaced the packing in the LHS cylinder gland (photo right). He was also quite anxious to get in the firebox and remove/replace fire bars … but it was later than he thought!


Sunday, 29 January 2017

Maintenance Update (eccentric, pipe, felt, coupling)

Wednesday 25th
Brian and David M took the left-hand eccentric rods off to be cleaned and give access to the eccentric strap. The left-hand inner strap was taken off for Gilbert to measure wear.

There is wear … there’s bound to be after 6 years of operation … but Carpo said it is fine for now and should last to the 10 year overhaul at which stage all four straps will need re-white-metalling.

John T and David M refitted the cladding round the main steam pipes. John then moved on to designing the final loco/tender link alignment gadget. This took the rest of the day, because of design discussions, options and measurements. John marked out a piece of steel ready to start cutting next time.

John G, meanwhile, cleaned up the three links and applied a shiny coat of paint. Oh, and the main drag link passed its NDT (Non-destructive test) on Monday.

Having warmed up a paintbrush, John then decided to apply another coat of Deep Bronze Green to parts of the cab and its handrails.

The grease nipple on the RHS rear tender brake hanger whole thread has expired received some stern treatment from Bruce - he “bushed the hole” (quote). This simply involved tapping out the hole in the hanger to the next size up, and fitting a reducing bush such that the original nipple now fits.

Gil mostly undertook measuring and was part-time gopher.

I attacked a pile of rail chairs, making a start to build up a stock of boot scrapers when the season begins. Anyway, John M keeps pestering me for an LMS one in crimson already!

Saturday 28th
David, Bruce and Gilbert cogitated over the eccentrics. You see, there should be a felt pad in the arrowed recess for wiping oil over the surfaces. There isn’t! This is not the first time that felt has  vanished. There was none in the first strap that was removed on Wednesday; so they took the second  one off carefully and hey presto: no felt pad! Another vanishing trick.

Jeff Lacey (Loco Dept) was observing, and he suggested that perhaps there was something on the sheaves themselves that was shaving the bottom of the felt pad. Over time, the felt has been worn away.

The chaps examined the sheaves and cleaned them up, but there no obvious step that presented a sharp edge. Where the two halves meet, there is a change in the surface, though not noticeably sharp. New pads were fitted. By end of day, the eccentrics were back in place.

For the whole day, John T was designing and working on making a Mk 2 version of the loco/tender coupling guide - out of metal. Many cutting discs expired; David welded a couple of length together, and progress seems to be being made. Later, I fitted the three drag links back in the tender, as John will need them in place to complete his gadget.

The new tapered pin for the rocking shaft had been delivered. David and Bruce examined it and felt that the taper was not quite correct. Furthermore, our tapered reamer needs sharpening. Bruce has some thoughts on correcting the taper fit.

I spent the morning painting rail chairs. After lunch, I decided to fit the tender right-hand rear brake hanger (the one previously with the duff nipple). It proved too heavy for me, so David and Bruce assisted while Gilbert offered encouragement.

I was given the honour of testing the nipple with the red grease gun.


Sunday, 22 January 2017

Maintenance Update (draw, punch, curve, press)

Wednesday 18th
The six of us were assisted at times by several Loco Dept chaps. Most notably, two chaps applied a second coat of bitumen paint to the rear section of the tender top. They couldn’t do the main coal space because Bruce and I were getting in their way!

What we were trying to do was to remove the nut on the end of the draw bar to check the quality of the thread. Access is below a removable panel in the tender, at the bottom of the coal chute. It’s a big nut! There is a key through the bar to prevent the nut from undoing and falling off. Between key and nut there is one large washer. The key has a split pin through it to prevent it from falling out.

It took Bruce & me the best part of an hour to remove the split pin. We had to break it off and punch it out, in the end. Then the key flatly refused to budge. Even if we had managed to remove it, how were we going to get a spanner on that nut? Anyone got a socket that large? We removed the inspection panel (labelled) but all you can see beneath it is a cup housing rubber shock absorbers! Going up from beneath, Bruce didn’t think there was room to fit a spanner on the nut. How on earth did we fit it in the first place?

Carpo suggested that we would probably have to remove the vacuum cylinder. John P [Loco Dept] inspected what he could see, and the agreed stance was that it looks sound and will remain a task to tackle at the 10-year overhaul!

John G spent the day painting: Cab edges, handrails; then cladding pieces. Brian also assisted painting the cladding from the main steam pipes.

Bruce and Brian had earlier shinned up to the top and removed the clack valves. After cleaning up there, Bruce took the clacks away for homework.

Bruce & I had been thinking about making the coupling up of loco and tender foolproof, and John T joined in on the discussion. After several ideas were bounced around, John set to on making a prototype out of wood.

The idea is to fit a gadget to hold the three links on the tender at the correct height and in line with their holes in the loco. Thus ensuring that they engage instead of bashing the drag box; and the securing pins in the cab can be dropped through their holes instead of down the side of the links (which causes them to get bent when going round a curve).

Several of us gave the tender a heave to test the effectiveness, and the Mk 1 prototype was deemed rather successful. A minor adjustment will be required to the slot for the RHS link (nearest camera on left), but the LHS pin dropped in easily! The idea is that the gadget is removed once the loco and tender are coupled. Best not make the final one out of wood, though, else someone will light a fire with it.

Gilbert repacked the gland in the LHS valve, so that is now ready for the front cover and the rest of the valve motion to be refitted.

Saturday 21st
My first task was to remove the RHS rear tender brake hanger so that the greasing point can be attended to. The thread inside the hanger has been stripped; so the nipple won’t stay in place, and you can’t get grease in.

Meanwhile, Bruce had been investigating the safety links (between loco and tender) with a view to making it impossible to jam the securing pin down the side of the link (which happened two years ago). He cut two “ears” from a length of pipe, and David welded these onto the links at the loco end, on either side.

Now, when the link is in place, it cannot be pushed far enough across for the pin to drop down the side of the link.

David did a little bit of “domestic” welding: Gil is having difficulty climbing up into the van where we have tea breaks, so Bruce and I move a set of steps there for him. To make them easily removable and yet stable, David made a pair of brackets to fit to them, which hook on and secure the steps to the van.

David’s main job was the LHS rocking shaft bearing. He had skimmed a couple of thou off the housing to make sure it clamped the brass bearings tightly. Further minor dressing was required to the upper brass bearing to make it a good fit inside the housing. Gil was assisting David with this. David also reamed out one of the bushes in the valve link (which connects the rocking shaft to the valve spindle). Gil had bought a new reamer!

Paul and Cliff [Loco Dept] were trying to fix the 50 ton press that we need for straightening the main drag link. I joined in, but it still took us 4 hours (according to Cliff) to get the hydraulic pump in the right position and working!

Once that was fixed, Gil applied heat to the link. When he ran out of gas, we decided to try the press anyway - and sure enough, it managed to get the bend out of the link! This will undergo an NDT on Monday to ensure that it has no internal fractures.

Alex and Graham [Loco dept] cleaned up more of the cylinder cladding and front running boards. They get covered in greasy, oily muck underneath. We intend painting the whole of the running boards once the mechanical work is completed, and before going back into service.


Sunday, 15 January 2017

Maintenance Update (bitumen, valves, snifting, coupling)

Wednesday 11th
There were hoards of us working on 2807 today! Brian, Bruce, Gilbert, John G and John T (oh, and me!) plus half-a-dozen Loco Dept Chap(ess)es, including Alex, Clive, Jeff, Tim and Peter.

Alex (nearest camera) skilfully having not painted herself and two chaps into a corner, applying bitumen paint to the coal space.

Thereafter, the rear section (with dome and filler) had to be painted, too. That was slightly trickier now that there was only one way up onto the back section! There ensued some toing-and-froing with a set of steps (that were being used to access the coal bunker of 4270 at the same time).

Brian dismantled the LHS rocking shaft, while, Gil and Peter looked on, practicing being gophers.

Apart from checking the wear, the intention is to ensure that the brass bearings clamp onto the rocking shaft with zero play. This may mean shaving a few thou’ off the casing (as we did on the RHS). All of this tightening of bearings is in anticipation of getting the valve timing spot on. It had been ‘not bad’, but slackness in various linkages makes it impossible to perfect.

John G and John T spent much of the day cleaning the piston valve heads. Getting the grot out of the grooves in the head turned out to be a challenge - one that required the use of a hacksaw blade!

Peter removed the nuts from the RHS cylinder cover in readiness for the piston to be measured for wear. However, the cover was rather reluctant to come off, so he wisely left this as a job that the Saturday gang can tackle. The cover did come off the RHS valve, though.

Bruce attacked Issue 55, and started to remove the snifting valves that are tucked away behind the
main steam pipes either side of the smokebox.

Although the nuts came off the studs fairly happily, the top of the valve unit couldn’t be lifted clear
of the base … because the cladding round the steam pipe was just getting in the way. Bruce is
indicating where a small amount of cladding will have to be cut away for easy access. The other photo is the top removed, and you can probably just see where the valve and its seat make

I fancied investigating the problem of aligning the three links (draw bars) between tender and loco,
which seem to cause other railways (notably the NYMR) a bit of a problem. First minor problem: the
team of painters in the tender! You see, I needed to part the loco and tender.

Checking that the loco wheels were chocked and the tender handbrake was on, I removed the securing pins from the links. I also put the fall plate back to cover the gap between loco and tender, foreseeing one of the dedicated team inevitably stepping backwards out of the tender and …. Aaagh!

While they were all slapping on bitumen, I decided to lift the wooden floor planks in the cab and give them a good clean. Coal dust and oil get jammed between them and underneath, too. Finally, the tender was gleaming black all over the top and the painters had adjourned. I released the handbrake and pushed the tender back a couple of feet.

Two years ago, NYMR managed to bend the RHS safety link (nearest camera) by getting the securing pin down the side of the link instead of through the hole in the end! This time, it looks as if the main (centre) draw bar must have been too low when coupling up, and hit the loco’s drag box; probably then bouncing up and into its hole. However, the bar definitely appears to have a droop!

Saturday 14th
Alistair, Brian, Bruce, David, Gil, John T plus several Loco Dept chaps were working away, mainly on the LHS valve and the rocking shaft. Alistair, John and I tackled the tender and the main draw bar.

Getting the valve rod back in place can be a challenge. It’s heavy (of course); awkward, and often
reluctant to be thrust back into its chamber. The rings on the valve heads have to be a close fit in
order to seal the steam. Persuading the rod to go into the bush at the far end requires skill plus a
pointy thing. Much waggling and pushing is required to line everything up. Hence, it took much of
the day!

Bruce had taken the snifting valves home to machine the seats and lap the valve head. He refitted
them today, and also wired up the insulation, which had previously be tied with string … which had
not lasted the course! Brian plus a couple of Loco Dept chaps gave the cladding a good clean and
tapped the bolt holes before fixing that back over the steam pipes.

David brought the tool that he has made at home ready to adjust the valve timing. He applied
yellow paint plus a clearly marked “2807” on it. We use yellow paint as a marker for our tools. He
then took measurements of the rocking shaft components that were taken apart on Wednesday,
and has taken the top cover home to machine it down a few thou’ to make a good fit. Thereafter, he
was trying to ream out some bushes in the rocking shaft arm and the intermediate valve rod that
connects to it. However, we could do with some sharp reamers!

You may have heard about a loco and tender becoming separated last year? It was apparently
caused by the large nut that secures the drag link to the tender drag box having a worn thread. The
thread stripped; the safety cotter pin behind the nut held on for a while, but eventually sheared, and
the loco and tender jolted apart, held (fortunately) by the two safety links. As a result, GWSR have
asked loco owners to inspect their nuts and check for any signs of undue wear.

Alistair and I worked on removing the main draw bar. This involved removing buckets full of coal
dust. Vis. there’s even plant life growing in it! Once the centre section was cleared, we could see
the panel that had to be lifted in order to extract the securing pin. That took a while, because it was
happy staying where it was - and I even cleaned and removed a small panel on the other side,
thinking that it was all one piece of metal that goes through … but it wasn’t! The deft use of a
screwdriver and copper mallet persuaded this small panel to lift, and we got the pin out.

Then we could remove the draw bar. By use of a standard-issue broom handle, Alistair
demonstrates how bent it turned out to be. We set up the 50 ton press. Carpo got some heat on
the go. John took over from Alistair, and we got ready to bend the bar back into shape. When it was
well and truly red hot, John inserted a lump of steel in the press and I started pumping away on the
hydraulics. Not a lot was happening! After a bit of puzzling and prodding, we discovered that the
little valve that releases hydraulic pressure had stripped its thread, and was not sealing the fluid.
Hence, I was doing nothing but pumping fluid round in a circle! Activity aborted. Hydraulic press
needs mending.

With part of the tender coal space floor removed, you can get to the nut. Well, you could after the
removal of three buckets full of coal dust, slack and grime! There was up to three inches of grot
lying on top of the vacuum cylinder. This is now a tad cleaner and we can inspect the nut next

On the bright side, I purloined a handful of coal dust/slack, and with skilled use of two sieves I now
have a goodly pile of 00 scale sized coal for my two-year old grandson’s model railway (that I’m
building in my spare bedroom).