Sunday, 10 January 2016

Carpe Diem at Urmston!

Seize the day! And as it was the first dry Sunday for weeks, Malc and I did just that. Alfred hasn't been steamed since the end of 2015 and we'd noted continued problems with trying to use the right hand injector. On investigation I found the ball in the right hand clack valve to be once again stuck firmly closed, preventing the injector from delivering water to the boiler. A bit of internet research revealed that the ball in the clacks on Alfred are not stainless steel as I'd assumed, but Viton rubber. This has the advantage of giving a better seal against boiler pressure blowing back through the injector, but are not as long lasting. Stainless and Viton balls are not interchangeable as Viton requires a tapered seat in the valve whereas steel requires a flat seat.

A phone call to Polly Engineering had a couple of new Viton balls in the post, and I fitted one to Alfred's clack. Time will tell if that will cure the 'sticking clack' problem.

So, this morning, in cold but bright sunshine, we set off for Urmston for the first time this year.

Pictures are by Jason Lau and are his copyright. Please c;lick on any picture for a larger image.

Malc, me, and Alfred on our usual prep bay. Note the blower on the chimney to draw air though the fire. Once we have some boiler pressure we can dispense with that and use the loco's own steam blower.

As we work on Alfred, Keith wheels 'The Beast' towards the traverser to put it on a prep bay

Malc puts Alfred through his paces on the test track

A Black Five on passenger train duty on the main track

Keith on The Beast on a passenger train

Me admiring a lovely 5" gauge Britannia Pacific 'Tennyson'.

The Brit is superbly detailed, right down to the leather seat for the driver and the plain wooden one for the fireman. Note the 'V' of exhaust steam plumes from the twin safety valves.

Time for Alfred to stretch his little wheels on the main track. I'm about to set off on the first of three circuits I made. Malc went round twice.

Another view of Tennyson on a passenger train

Disposal time; Tennyson on the prep / disposal bay

Alfred sans tender at disposal. We've dropped the fire (the whole fire grate can literally be dropped out from under the firebox) and opened the boiler blow down valve (still issuing a slight wisp of steam) and the lubricator blow down so Alfred is now 'dead'. I'm shoveling the ash out of the smoke box while Malc gives the cab a clean round with a blast of compressed air. Next job will be to use the flue brush to clean the boiler tubes before blasting the tubes and smokebox with compressed air to get rid of the last of the grit, coal dust, and ash.

What a great day's running, including several runs on the big (main) track. It's quite an art to keep Alfred going on the main track. One has to ensure, before leaving the station, that the boiler pressure is at max, water is a full glass in the sight gauge, and the fire is in first rate condition. Then one takes a run at the curving climb out of the station and on reaching level ground the regulator can be eased back, the reverser pulled back a couple of notches, an injector put on to replenish boiler water, and a round or two put on the fire (quickly, as having the firehole door open lets cold air in and kills boiler pressure).

The secret is to keep on top of all these parameters, especially the boiler water level which must never be allowed to get too low or boiler damage or worse may result. If one runs low on boiler pressure one can always stop for a 'blow up' (get the fire right, and get the boiler pressure back up to where it should be). 

On two of my circuits I made it all the way round with no problems, even arriving back in the station with Alfred blowing off. On the last run I was hurried into setting off with less than full pressure and was on the back foot from the off, only just made it all the way round, arriving back in the station with quite low boiler pressure after a touch-and-go slow climb of the final gradient.

Everyone who rides behind Alfred is impressed with how well he steams, and today we had both injectors working fine, so no technical problems at all. Lets just hope the new Viton ball in the right hand clack has cured its propensity to stick closed.


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