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My working life started in a textile engineering factory aged 15, working on industrial size knitting machines up to 80 feet in length for S. A. Monk Ltd. of Sutton-in-Ashfield.   I learnt to assemble, repair and install them around the world, and now that the original manufacturer has gone, I have spent the last 10 years self employed, maintaining these 'fully-fashioned' knitting machines. As a result of needing to make parts, my workshop contains a Bridgeport milling machine, Colchester Student lathe, Myford M lathe, Centec 2B miller and a small surface grinder.
My interest in model engineering came from my father, the village plumber, who built a 1.25" scale traction engine, and also the Great Central Railway line ran through the village.   Plus, Sam Monk (my ex boss) had a 10.5” track around his garden and 3 or 4 locos, one a Duchess.   For many years I was away from home too much to get involved, but then I did build a 3 1/2" gauge Britannia, which gained a silver award at London, and 1st award at the Midlands and Harrogate exhibitions.
I always wanted to build a Gresley 'P2' but felt I did not have enough time, then in 1997 I was offered a part-built Merchant Navy which I thought it would be a time saver. In hindsight that was probably the worst thing I ever did, as I have ended up stripping it right back ! The assembled chassis had been constructed with Marshall valve gear, a steel boiler with boiler casing and a cab.
As I had no drawings to work from I bought a number of MN books to study. I constructed a new boiler to the correct outline based on the design of a Britannia boiler, but modified for three central safety valves and twin top feeds; it has 3 superheaters which are radiant, 32 tubes and a small combustion chamber. The firehole door was made 1/4" wider and 1/8" taller to allow easy firing with a large shovel of coal, so I can easily feed all areas of the fire.
The cab was completely re-made to fit the new boiler, as were the sides and top. As I work in an industry where accessibility is critical I used the same idea on the loco. So the casing top is secured by two thumb screws under the smokebox front cowling, and at the back this clips under a lip on the cab front. Similarly the side panels include 2 pegs on the rear which locate into the cab front, and the front of each side panel slots in and is secured by a single screw. The 3 three panels can be removed and refitted in a couple of minutes, allowing easy access for oiling up and inspection of the (multi-modified valve gear).
The tender body is steel plate with brass inside, and has an inner coal tray made from acrylic sheet which can be lifted out; there is also a generous cut out at the front to allow good access to the cab for driving. The vacuum tanks on the tender are dummies.
On first steaming the loco it was obvious that the valve gear was hopeless, so I stripped the whole lot off and threw it in the dustbin. I have a friend who used to work in the B.R. drawing office at Derby, and together we worked out a new version of the Marshall type valve gear, chain driven of course. This will allow the loco to be notched up to 30%, and on the track this performed must better.
A drip feed under the casing keeps the chain and other valve gear components lubricated, but although mine does not have a sealed oil bath, there is a large sump tray which catches oil drips - otherwise I would be in trouble for dumping oil on the track.
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