Up onto the footplate I went, and looked in the firebox. What a sight! 3/4 of the grate back from the front was completely clear, whilst around the firehole door lay a strong mound of burning coal! The water gauge glass showed 3/4s full and the pressure gauge told of a healthy 80psi. What more could you want? I will admit, myself and John were gleeful as we cast the pile of wood back off the engine and onto the floor! All I had to do was make the necessary checks and then spread the crackling mound across the back half of the grate as much as possible. More coal was then added, as well as putting a bed 1-lump thick across the rest of the grate. It was then time for a cuppa' before oiling began. Later on, with 140psi on the clock, we moved noisily but gracefully out of the shed and began cleaning. Between the two of us, though we were rushing, we managed to get the 38' looking very presentable and even gave her some festive decorations...including a her own Santa Hat! At 10am, having washed up and changed, we steamed out of Shack on the first train. 3803 steamed beautifully with a thin fire and steam heat on at 40psi. The pressure gauge read between 225 & 200psi throughout the run with a strong water level being maintained. I was very pleased. Mind you, 3803 is a very economical machine. I have used a useful diagram from Steam Launch.Net to demonstrate...
So, the diagram demonstrates a simplistic overview of a Superheated boiler. The fire grate can be clearly seen, as can the various flues (large & small). The heat from the fire of course travels along the flues and heats the water in the barrel. The hot gases then escape up the chimney. Combustion in the fire can be controlled, not only by firing effectively but also by changing the levels of air that enter the fire, both from above and from below. Primary air enters through the Damper doors in the ashpan, whilst Secondary Air enters through the firehole door. Bad smoke is often a result of bad combustion or bad firing and this can be slightly improved when in the 'shut off' position by cracking the firehole doors slightly. The smoke will thin due to the added air and combustion will slightly improve. One may even notice a pressure increase. Eventually, you will find a happy medium. However, the main thing to remember is that the fire, particularly on this engine, needs to be kept relatively thin. She does appreciate a strong back end occasionally but the main thing to do is to keep the centre section of the grate where the slope begins covered. Any overfiring will often result in clinker and lowering of pressure, whilst underfiring will soon drastically reduce the steam in the boiler! For example, a whole in the fire does no good at all and must be filled asap. With superheating, the loco uses the steam once it has been reheated in the superheater. Saturated (wet/normal) steam leaves the boiler and is taken into the superheater elements, held within the larger boiler flues. This reheats/dries the steam making it more economical, especially when the driver notches up and uses the regulator correctly. With John at the helm, I needed very little coal. In fact, 'just enough' was often the key to success. Anyway, back to us. After a steady run to Market Bosworth, we were held for 8 minutes whilst Santa saw more children...
After a short break at Shack we were out again at Midday, with the trip being just as successful as the first. 3803 steamed well and we generally had a good time. The sun was also fabulous...brilliant for early December but a little blinding when travelling tender first! After the 2nd trip, we decided to take water. Whilst up on the tender, I caught this quick snap looking down into the tank. I fear that the bag on the column is in slight need of replacement!...
After another coffee and a good chat with Rick AND a fan of this blog (thanks for coming and chatting to me, sir. Always nice to hear that somebody is reading!), we departed on the 2pm. This was another good run, though I did have a bit of a hole-plague on the way down to the Shenton...the pressure sticking at around the 180psi mark...my fault, not the loco's. However, all was well again when we left Shenton with 215psi on the clock and a full glass after a swift run-round. We had been told that Rick and a fellow enthusiast would be up on the recently cleared embankment near the Far Coton Cutting. They had asked for smoke if possible but here you really don't get any unless you've massively over-fired or you've shut off for some reason. However, we did ensure that they got a lovely trail of white exhaust against the glow of the already slightly setting sun! As we chugged up the bank (with 3803 happily making pressure) we spotted the two hi-viz jackets on the bend. After whistling, John gave her a bit of 2nd valve...not enough to go mad but more than enough to put on a good show (she sounded fab). The resulting photograph is spotted below...its a beautiful shot...
Roaring past, we received a thumbs up from the two photographers, after which John shut back down into pilot for the final run into Market Bosworth. Thanks for the shots Rick...lovely! Back at Shack, we had a 2.5 hour break before a night train in the evening so we took a good rest and indulged in some bacon on the shovel and countless cups of coffee. The night train later on was also fab. I'd never fired at night before though I have travelled on the footplate. The glare from the fire was blinding but what a fab experience. I hope to fire at night many more times in the future! You can't see a thing and you only have a parrafin lamp on the water gauge but who's bothered?! Its just so evocative. After the train, we duly disposed and left the railway. I must thank John for such a good day and for passing me on my first (of 3) firing exams. What an amazing day!...
2 comments:
Was nice to meet you on Saturday and well done on passing your exam.
Hi Sam
AS always a great blog. Good to hear that you are now well on the way to being passed fireman.
Are you rosterd on the 18th? If not see you at the pools on new years day.
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