Saturday, 26 March 2016

Maintenance Update (blow down, AWS, flange, paint)

Wednesday 23rd
Not a lot to do today. Gil has made a short list of things to look at when we’re over a pit … which we were not. The more important thing that we could do was to test-fit the exhaust pipe from the blow-down valve. Blow-downs are only performed when untreated water is used in the boiler, so we have no need to do one at GWSR. But if we go to other railways, we may have to blow out the salt-laden water.

Bruce had fabricated a template thin pipe for Carpo to use as a guide. Carpo has now configured the real pipe to match the template. John G and I tested its fit. It has to meander through various linkages and pipes, and avoid the vacuum cylinder ... and not foul the damper mechanism …

We bolted the flange in place; arranged the pipe in its best position, and marked the pipe and flange. Carpo came and inspected our efforts, and we all decided that it was as good as it could get!

The flange will now be brazed on, and the tail of the pipe will need angling at about 30 degrees to ensure that the exhaust steam is directed into a pit. A jet of water squirting out with 200 psi behind it, and instantly flashing to steam, would be a tad too exciting if it were not directed into a (clean) pit!

Thereafter, John & I played with some conduit, test fitting it on the loco.

We have a few pieces (two long pieces that do appear to be off 2807), but some is missing and others are not from our loco! There’s a ten-foot gap to fill (but I think I know where there is such a length sitting idle); plus the front section that turns under the front of the loco, and a jigsaw at the back. We have a rear section, but it is clearly not from 2807. It has a useful bend to match our frames, but then goes too far backwards, and misses the battery box by almost two feet. However, it can be modified to suit. There’s a pipe comes down from the AWS box in the cab and T’s into the long conduit. The conduit then feeds down into the battery box. So, I think we can complete it!

Mike W joined us at lunchtime, and he cleaned up some of the conduit sections. John spotted where someone had chipped his beloved paintwork, and touched up a few places on the loco. A couple of handles in the cab then received treatment to polish them up and brush off the rust.

Gil, Fred and Bill were working in the siphon van at Winchcombe. There is another pair of doors that they are overhauling. One of the pair is in relatively good condition, but the other … well, it looked to me as though it would be a throw-away job! But they are happy in their work.

Saturday 26th

The weathermen promised rain, particularly for the afternoon, but boot scraper stocks are very low. No option but to soldier on and clean up some rail chairs despite the weather. Actually, there was no serious rain until 3.30, by which time I had cleaned 8 chairs. Black bottoms abound!

Bruce & Gil spent the day playing with the blow-down pipe. Somehow, my markings on the pipe to line the flange up correctly had disappeared. So, it had to be done again. As I was the most flexible of us, I stuck my head down the hole (under the shovel plate in the cab) and marked the flange and pipe again (in a different colour). Bruce brazed the flange in place, and the subsequent test-fit was spot on. There’s not exactly a wealth of room below the cab - photos will perhaps demonstrate:

Bruce fluxing the end

Flange brazed in place

This photo is peering down through the hole in the cab floor, directly below the firehole. See how the pipe has to bend sharp left to avoid the vacuum cylinder.

This one is taken just in front of the cab steps.

Subsequently, the pipe was shortened by about 2” and bent inwards slightly to be sure to eject steam into a pit.

When the boiler is empty, the blow-down valve pipe can be used to fill the boiler, so we needed to cut a bit more off the end, as it almost touched the ground.

On Wednesday, 2807 should be out and over a pit, as she is scheduled to enter service on Thursday 31st. That will give us a (brief) chance to look underneath. There are a couple of minor things that require attention. Gil has made a list, thus:

  • Front damper: cinders had been seen to have fallen through during last week’s trials;
  • Tender nipples: grease does not appear to have been applied to the nipples on the tender for quite some time; *
  • Number plate fixing: it would make life easier if nuts were welded on the inside of the cab, otherwise it’s a two-man job just fitting/removing cabside number plates;
  • Rocking shaft fitted bolt: there’s one left to do;
  • Taper pin in drain cock linkage: the loose pin needs replacing with a new one.
* I believe that we should take responsibility for greasing (and possibly some oiling) of places that are not necessarily common to other locos. The drivers will happily fill up oil pots, on a day-to-day basis, but may not think to grease bearings that maybe only need doing periodically. I believe that we should undertake a routine oil/grease on a monthly basis, because we have experience of knowing what needs doing, where, and how often.


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