Friday, 8 May 2015

3803: A Warming Fire...

Hi everyone. With the prospect of going to Shack Friday rather than Sunday, I thought why not. As long as steam is rostered to work on the Saturday, a Friday task is often to put the warming fire in. For those not in the know, a warming fire is exactly what it sounds like. It is not only time consuming but also bad practise and potentially damaging to take an engine from cold to steaming straight away and so a gentle warm-through is performed. The boiler of a locomotive often contains several different materials in different conditions and with different expansion rates. Therefore, so as to impose the least possible stress on each of the separate components, the boiler is warmed through gently, often over a period of well over 12 hours. Today for example, the locomotive was lit up at just after 1pm, but she won't be expected to be in service until around 10:30am tomorrow morning! To start preparations for a warming fire the engine has to be thoroughly checked over as normal. All fittings, mudlids, plugs, tubes and stays have to be looked over as well as naturally checking the water level in the boiler. 3803 had been cleaned out on Wednesday following our excursion on Monday (click here for that) and so was pretty much ready to go. With a long handled Lucas shovel that came to hand, I spread half a dozen shovels around the back corners before getting some dirty rags together. "Ignition!"...
The warming fire is only lit on the rearmost 1/3 of the grate, if that. We normally aim for a fire that starts at the rear of the box, makes its way 18"-24" in and then slope it at around 45 degrees until it reaches the firehole doors. The rest of the grate remains completely clean and untouched. With the rags blazing on top of the few shovels of coal, I added a good half a pallet or so of dry wood and a few rotten bits I'd found lying around, and then added a final few oily rags for good measure. The doors were then shut and the damper opened to get the initial heat there. Then, using the Lucas again, I added quite a bit of coal to black the fire out. The fire was built up in the normal manner, with little at the bottom and a lot at the top. I tend to make the fire up to the level of the firehole door or just above to start with. This is because you must remember that all that stacked wood underneath will burn through any minute and the bed will fall considerably and you've got to have something to bite on...
With the fire burning brightly and quietly, I left 3803 to it. The next job was to get the Brasso out and, in a lonely fashion, make a start on cleaning the cab brasses. When you're on your own, its a quiet site, really quiet. There is nothing in the air but birdsong and the rustling of trees as the sky that had so threatened rain finally let go. Outside however was a bit of interest: the re-sited boiler of Dunlop No7. The boiler is now ready for water with all of the tubes and stays fitted. Its really coming on...
Having had a quick gander at No7s boiler it was back into the shed to carry on with those brasses over a few sitcom repeats played on my phone. (You need something to stop you talking to yourself!). Meanwhile the loco makes all sorts of strange noises. It bangs, it creeks, it groans. Gradually, she's expanding, so little in fact you wouldn't notice, but she does. I sat with the engine until around 4:30pm, by which time she'd been lit for well over 3 hours. The fire was still doing what I'd expected, burning bright at the foot of the slope and with the fresh new coal still sat at door level. The natural progression of the fire will gradually eat into the fresh coal as the bed burns down, thus basically feeding itself. Before I headed off, it was time to add those final few shovels which would mean the difference between no steam and 10psi in the morning for Fireman David. With the fire crackling away, gauge glass now isolated and the lights gradually being switched off, we take one final look at 3803 before I left, in the gloom of the engine shed...
Naturally, as I left, it was now raining well! Luckily 3803 was tucked up and boiling quietly away to herself in the shed, in the dry. Thanks very much for reading guys, Sam...

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