Back to the normal routing for this turn - a Wednesday and a Yellow timetable: that's four round trips steam hauled back to back with four round trips of the DMU. As usual, I sign on at 05:45 with Fitter Bob, who goes off to make his breakfast while I go down to the yard with my cleaning bag, shovel and a 'stop board' to light up the B12.
It's warm, as it has been in service since Sunday, and we have 20 psi on the clock since last night. I collect a shovel and a broom from the cleaning store and climb up to look in the smokebox, which all looks intact so I use the tools to scoop out all the ash from yesterday. Since the smokebox door seal is integral to creating the draft to drawer the fire, I brush around the seal area before closing the door and tightening the dart.
Returning to the cleaning store I pick up a bucketful of rags from the bin which is full of dirty rags and paraffin, and put them on the footplate. I open the firehole and with my cleaner's cap on backwards have a look around inside with my torch, to check the stays, the brick arch and the fusible plugs - all areas which might cause concern. Nothing is amiss today, so I take the bent dart from the tool rack on the tender and clean the ash off the firebars, pushing it all forward. When I am done I take the rake, like a 10' iron garden hoe, and clean the rest of the grate so the ash falls through the bars into the ash pan below.
Next comes a layer of coal, heavier on the inclined section at the front and only one lump thick over the rest of the grate - I want to minimise the time it takes to reach incandescence and hence minimise smoke. I check the dampers are both shut before throwing in a long piece of wood with a flaming rag tied to one end, to the front of the firebox followed by more wood to the same area. another one goes in the opposite corner, one in the middle followed by more down the sides until I have the whole grate ablaze with burning timber and paraffin. I shut the door.
It doesn't make so much smoke, and after 15 minutes or so Fireman Harry adds some more coal. He's been here for a while and has put the hose in the tender. I set to with the rake to level off the coal, to allow Fitter Bob to load some more later - it's all heaped at the back of the tender, before going over the running boards and frames with some oil & paraffin. Before long, Driver Keith is here and we have enough pressure to start the Westinghouse brake pump.
Driver Keith opens the drain cock on the pump and then the steam valve, to drain out the condensate - the pump operates lethargically for a bit spraying water everywhere, before warming sufficiently for us to shut the drain valve and develop some air pressure in the braking system.
Now we have brakes, we can push back and Keith can get underneath with the wheeltapper's hammer. Fireman Harry uses the injectors to prepare for blowdown, and with a full glass blown into the pit we dive underneath to clean the ash pan and fit the spark guards. Next it's coal, and Keith and I go off to get changed while Fireman Harry refills the boiler.
Dressed in our Sunday best and back on the footplate, Keith and I take the loco out of the yard and into the platform. I resist the temptation to put a round on as I don't know Harry yet, and it's his fire at the moment - though it looks a bit thin to me.
Little do I know! Back on the footplate, Harry puts a light round on and we roll gently down to Sheringham with may 40 minutes to go until the fist train is due out. He builds it up very gently on the way down, adding to the front but leaving the hole developing in the middle.
We tie on to our train and I observe as this very experienced crew take us up to Holt and back. We take water before the second train departs and on the trip up I tell Harry what I've observded him doing, and he shares his technique - some of which I have heard from others.
He says he doesn't use the front damper, it's shut all the time. He fills the inclined area of the grate with a thick wedge of coal and leaves it to form a mass of retained heat right under the arch - he tops it up occasionally but since the damper is shut it burns through very slowly.
Secondly, he allows the middle third of the grate to run to holes, so we can see the bars, to control the fire, keeping the sides covered and the firebox wrapper hot.
Lastly, he fills the back third with coal and is careful to get it right under the door, in the part of the box that slopes towards your feet. When the loco is underway, you have a 'billiard table flat' fire.
I can see that with holes and a big mass at the front, the boiler will sit at 150 happily; fill the middle third in and it will come around very quickly - if you fire the front, back and both sides gradually while stationary and with both dampers and the doors shut you can build in heat into the fire and the poor draft and hole in the middle keeps the boiler temperature low enough to avoid blowing off; when you get the 'right away', open the rear damper a little and start filling the hole in as you get out of the station, adding more to the middle as the driver starts to use steam and the draft starts to make heat.
It's easy for the rookie fireman to panic and throw more coal on the fire than it needs - you must fire slowly, control your rate, and be patient for it to come around. If you fire slowly and let the coal catch, you can see the effect it has on the gauge before you overdo it - of course, if you have a lot of building up to do, you need more time to build it slowly, so you must always watch your clock.
You must learn to trust your judgement - believe in your holes. Running round at Sheringham, I had a large hole and some water space - and I had twenty minutes to take on water. Fireman Harry saw this hole and suggested I will it in - I said "I don't want to do that, I have twenty minutes to wait". He said "you're in charge" - and I filled it in anyway. And what did it do? Blew off while taking water - so, trust your judgement.
So yes, we blew of and not for the first time that day but, we did get back to shed with the boiler full and the fire perfect for disposal.
During disposal we raked out the clinker as normal and Fireman Harry showed me how to rake over all the ash to remove clinker and then spread the ash to keep the whole grate warm.
Another good day, with smiles all round.
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