Sir David - 7 1/4" Loco built by Roy West.



The builder is a coppersmith and sheet metal worker by trade and had a number of locomotives under his belt before he embarked on this project. No commercial castings were used in the construction of this loco. The loco comes with the original hydraulic boiler certificate, a wooden box on casters, a hand pump extension rod, a stainless steel shovel and two scale hand crafted lamps.

  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'

The builder made his own patterns and kept a full log of the build which details some eleven thousand parts that have been fabricated during the build. Where appropriate the builder made several modifications to the original design and I have done my best to detail these at the appropriate points in the description.

The cab and saddle tank are made out of 20 gauge brass with the saddle tank ends being flanged 16 gauge copper. The removable rear section of the roof has been strengthened to ensure the cab keeps its shape when removed. There is a gap of about 5/8" between the boiler cleading and the water tank and approximately ¼” of ceramic lagging which should keep the water in the saddle tank cool.

Cleading has been added, along with ceramic sheet insulation, to the lower front of the firebox (an area that this quite commonly missed) and cleading has also been extended to the boiler backhead where dummy washout plugs have been included along with a tray above the firebox door for the footplate crews cuppas. The backhead fittings are of a quality you would expect from a master craftsman and include two water level sight glasses with blow down valves. Each of the steel levers in the cab has a bronze handle. The pressure gauge has been flanged giving a scale appearance.

  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'

The boiler is commercially made with a working pressure of 100psi. The boiler was built by Daryl Lynton of Cornish Boilers before he retired and was constructed in September 2000. The loco has never been steamed but has been run on compressed air for two and a half hours. A hand pump, not present on the original design, has been neatly concealed below the cab floor and is accessed by removing a very neat brass cover. There is also an axle pump and an injector. The injectors came from the late Norman Spinks. The cab includes a very neat rocking lever to activate the drain cocks with brass plates stamped ‘open’ and ‘shut’ attached to the cab floor. Another rocking lever, neatly attached to the left hand cab side, activates the water supply to the injector.

The running boards are steel and have been made in a single piece which varies from the original design. The chequer board in the cab is hand crafted for a scale appearance. The inner smokebox is constructed from 1/8th inch thick aluminium tube to avoid any issues with rust. There is a four element stainless steel superheater and a four jet blower to ensure a good draw from the fire. The cylinders have been fabricated from gun metal. The pistons have been fabricated from bronze and have ‘O’ rings fitted. The chimney has been fabricated from bronze. The pumps are constructed from bronze and gun metal and all are fitted with ‘O’ rings. The whistle at the front of the cab is fully functional and another nice feature is the nickel silver handrails. The buffers have been fabricated from cast iron.

The main lubricator has been made to the builders own design with his main inspiration being drawn from the Wakefield lubricator design. This lubricator is just behind the front buffer beam and contains a cap which has been fabricated to include a dipstick. There is an auxiliary feed that provides an additional water source for the injector that is located below the read buffer beam allowing a feed from an external water tank. The cap contains a seal to keep the connection air tight when not in use to ensure the injector continues to function.

  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'
  • 7 1/4" guage Loco - 'Sir David'

The two twin pot oil wells on the running boards feed oil to the reservoirs at the top of the horn blocks and the horn blocks have oil ways from the reservoirs through to the horns to keep those hard to reach areas well lubricated. There is a nice wooden toolbox on the running board. The box doesn’t actually open but really looks as if it should. The loco is painted with cellulose paint. In general 2 coats of undercoat and 5-6 top coats of cellulose paint have been applied. The parts painted in black have also been lacquered to give a hard durable finish. The painting was carried out a year ago so it has been given time to harden off. Where black bolts have been used to secure any black painted parts then these have generally been chemically blackened rather than painted. The majority of the brass items have been lacquered including the pipes and window frames.

The valve gear has been constructed from mild steel and then case hardened and are all fitted with bronze bushes. There are additional oiling pots on the motion to offer better lubrication. The crosshead slides have a circular design for lubrication rather than the designed diamond pattern as the builder feels this will offer better lubrication. The boiler blowndown valve and the grate pins are easily located. The frame stretchers and drawbars has been made of thicker material where the builder felt these areas needed to be strengthened. The suspension too has been stiffened after the main build where it was felt that the loco, as designed was a little soft on its springs.