By Keith Skillicorn
This model is one of my favourite Archangel locomotives.
The model, built in 1982 represents “Princess” a Kerr Stuart Skylark locomotive built for the Campbeltown Coal Company in 1900. The Campbeltown and Machrihanish Light Railway took the loco over in 1906 and apparently worked it into the ground. With a very short coupled wheelbase the loco could negotiate very sharp curves. The loco had vacuum brakes fitted eventually and was therefore able to work (short) passenger trains. Some parts of her led a charmed life though, the rear of the cab and one of the sand pots ended up on Chevalier.
The loco is actually a pretty good scale model in most dimensions, except that Stewart thought fit to extend the bunker rearward to accommodate a standard Archangel Meths tank. This gives the loco a reasonably long duration on one fill and given that it only has a two wick burner the Meths will last about 15 to 20 mins.
The boiler is a simple “pot” which has a regulator, safety valve, vacuum tap and pressure gauge fitted inside the cab area. I have retro-fitted a top up valve beneath the front dome to facilitate filling the boiler whilst the loco is in steam. I have found however when in use if I pump even a relatively small amount of water in it kills the pressure completely and you then have to wait until she boils again. This I’m sure this is because of the very marginal heating from the two wicks.
The valve gear is of the rocker type to bring the motion from the eccentrics in between the frames there are a couple of levers and shafts which transfer the movement to the valves which are situated on top of the cylinders. Lubrication of the cylinders is taken care of by a displacement type situated on the left hand side of the footplate in the cab.
How does she run? Very well actually. The loco will run slowly and pulls its train of C&M wagons around my railway a treat. The front wick is only partially shielded by the bodywork and is susceptible to drafts and you find that she is a poor steamer in windy conditions. The solution would be to add another wick tube and to bring down the height of the wicks more to the old Roundhouse proportions. I’m not gonna’ do it though, it’s all part of the “Charm”.