Saturday, 24 May 2014

Putting The Fire On...

Hi all. A quiet and very, very wet day today at Shackerstone. I arrived at 10:30am and proceeded straight to the engine shed through the pouring rain. Inside the dark engine shed stood the bulk of 3803 over the pit, with "Sir Gomer", "Dunlop", "Richard" and "Blue Circle" all hiding down the far end, cosy and dry. The weather outside was just awful and the Class 73 looked saturated as it occasionally battled past the shed with the sparsely filled 4-coach train. On my own, I thought I'd clean the frames on 3803 and so, starting at the rear of the tender, I set to with the paraffin & oil mixture. Scrubbing away to remove the thick grime, and then using soft, clean cloth to buff up the paintwork, the job was certainly worth doing. I worked my way down the entire fireman's side of the huge 2-8-0 before I decided that it was time for a cuppa'. After around 12:15 I decided that I would begin preparations for the engine's warming fire as she would be out tomorrow. The locomotive is far too large to light on the morning of a steaming from cold, besides this practise being totally frowned upon and proven to be damaging.

The beginning of a warming fire starts like most others, with the full checking over of the locomotive. With 1/2 a glass of water confirmed to be in the boiler, it was time to check the firebox. The grate was very clean, as was the ashpan and the entire perimeter of the firebox dry. The fusible plugs, stays, tubes, flues, brick arch, seems etc should all be checked. The mudlids around the foundation ring, firebox sides, throatplate, corners etc should all be checked for leaks, just in case, as should the internal fittings of the huge smokebox. If all is dry, the locomotive is confirmed watertight and safe to light up. Our warming fires are lit at the back of the firebox, working forward towards the slope on the grate. I started by adding a bed of coal 1-lump thick and then started a bright, wood fire. The wood is then covered with coal and, over the course of a few hours, a large mound of coal built up at the back of the firebox only. By no means is a fire started on the remaining 3/4 of the grate. Slowly but surely, the smouldering fire at the back of the box will slowly heat the boiler, allowing the various different materials used in its construction to expand slowly at their own paces. Different materials that expand at different rates should not be rushed. The locomotive will be made safe but will often burn through most of the night. A huge engine such as 3803 with such a large boiler may take up to 12 hours on a slow burning fire before she thinks about making steam, though some mornings 10 or 20 psi may be found on the clock by the arriving fireman.

Though a fire burning all night may seem odd to some, it is by far the best way of warming the locomotive slowly and safely. Rushing the expansion and steam creation in the boiler from cold may induce extra stresses, eventually leading to tube or stay failure. With a good warming fire, 3803 will come around in her own time with no rushing and thus the life of her large (and very expensive) boiler will be lengthened. At around 5:30pm, I thought it was time for home so headed off leaving David to keep a final eye on 3803. The fire was now burning away nicely with a good wedge at the back end and all dampers closed. The loco was by now very warm around the foundation ring, but cold still on the manifold, after around 4 hours of burning. The front of the smokebox was also only luke warm, showing just how long it takes to correctly warm up such a large boiler! Best Regards, Sam...

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