Monday, 28 March 2016

Back on the big track at Urmston

'Alfred' in action at Urmston

Today is Easter Bank Holiday Monday and trains were running on the Urmston track, as they were yesterday. The weather was terrible yesterday so we chose to attend today, though this morning it didn't seem a lot better, with some rain.

Malc is over the worst of his post-hip replacement mobility problems so he came with me, his first visit for many weeks.

Maybe it was the morning rain, but there were few customers to ride the trains today so there was plenty of spare capacity on the 'big track' with few passenger trains running. After a few circuits of the short track we noted this spare capacity and decided to take Alfred onto the big, main, track around the perimeter of Abbotsfield Park. It's not the first time we've done this but now we have more experience with 'Alfred' (and a correctly working right hand injector!) it was time for another go.

I went first and 'Alfred' performed magnificently. Once underway I could 'notch back' the reverser to just short of mid gear to make best use of steam; this cuts off steam admittance to the cylinders early in the piston's stroke, allowing expansion of the steam to do the rest of the work of pushing the piston down the cylinder rather than wastefully admitting boiler pressure steam for the full stroke. This process is akin to changing up to a higher gear in a motor vehicle.

The new injector, with its instant pick up and fast feed rate of water into the boiler minimises time fiddling to keep the boiler topped up allowing more time to keep on top of the other factors vying for a driver's attention. I found I needed to use it twice, and also to fire the locomotive twice, on a circuit of the park. Rapid shoveling during firing reduces the time the fire hole door is open (opening it allows cold air to be drawn through the boiler tubes, killing boiler pressure). Judicious use of the blower during use of the injector was necessary, to compensate for the pressure drop induced by the double whammy of loss of steam and influx of cold water into the boiler use of an injector brings. And of course the blower needs to knocked off completely while the fire hole door is open to minimise the inrush of cold air.

The accumulated experience of weeks of practice on the short track, plus the help from the new injector, meant not only did 'Alfred' complete a circuit of the big track with no problems, he climbed the final long gradient to the finish in fine style, running into the station with 3/4 of a glass of water in the gauge glass and blowing off steam through the safety valve!

'The Beast' being prepared at Urmston

While Malc had a go on the big track Keith invited me to drive 'The Beast' round it. This is a much larger locomotive and with so much more reserve in it's big boiler and firebox it is considerably easier to drive than 'Alfred'. In fact as long as it is fired before leaving the station, and the boiler water topped up, all one needs to do is operate the regulator and brake to drive it. No need to plan your firing or boiler top ups, or even notch it back.

I think I prefer the challenges of driving 'Alfred'!

Here;s a video of a 5" gauge Princess Coronation (my favorite prototype loco) 'Duchess of Sutherland' doing a circuit of the big track at Urmston. 'Alfred' does the trip more slowly, obviously, and the most testing parts are the first gradient (long but not as steep as the second) which starts almost as one leaves the station, the first tunnel marking the foot of the bank which continues until the end of the railings either side of the track. The second, steeper gradient is almost at the end, from the second tunnel to just before arriving back in the station. If 'Alfred' has not been carefully nurtured during the circuit, it's this last gradient that will be the show stopper :

Duchess on Urmston's big track


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