No. 8 "Engineer"

No.8 "Engineer"

No.8 is finally up and running as a complete locomotive. As a first venture into locomotive construction and a lack of machine tools, many parts were purchased complete; in essence No.8 was a kit, built around a non-standard frame.

The source of inspiration for Engineer has been parts of many other locomotives seen at shows, in real life and in books. I was very impressed by the look of the Bagnall 2-6-2 locos used in India, and more so when I saw a GRS Gunga-Din as a model of the class. I have also always been fond of the Stanier 2-8-0 design from the day's of my father's Hornby Dublo models.

From these beginnings, I took measurements from my own No.4 and put together an arrangement which captured the look I wanted.

The list of parts, suppliers, prices where available and other relevant information can be found here, or click one of the section headings below for pictures and details.

Basic Construction

1. Chassis. Two flat frames make up the chassis with frame spacers (R/H) between. Since I'm using R/H running gear, this method ensures the components are compatible from the start. The rigidity of the frames is assisted by the front footplate and cab floor plate which give me stability. The running boards are then cosmetic. The frames have the axle and other holes provided by the laser cutter at production time - these are more accurate both in position and size than if I had drilled them afterwards. From the component parts, I constructed a rolling chassis with only a little hand finishing, mainly due to the design evolving.
2. Boiler.  The smokebox locates the front of the boiler that is itself bolted to the trailing edge of the front footplate. There are several choices available for the boiler supply, including bespoke and self build, but following experience and availability, I have chosen from the R/H range. This way, I have a complete boiler, fitted regulator, safety valve and burner assembly as a tried and tested unit. The boiler purchased is as fitted to the R/H Argyll, this having a slightly longer boiler than my No.4. As I have put a gas tank in the tender I therefore do not need the R/H tank or gas regulator and as such the boiler was supplied without. I do however require a boiler water top up system as the gas tank is larger than standard. This is a valve supplied by Brandbright that replaces the normal boiler filling plug under the dome. The rear of the boiler is held in place by a foot onto the cab floorplate.
3. Cab.  Sheet brass. This item is a non-structural part as all fittings eg the servos are bolted to the cab floorplate. This means that for setting up and maintenance, the cab can be completely removed. The use of micro-servos has left a very clear cab with sufficient clear space for both driver and fireman. The pipe for the gas burner goes under the floor as do the servo wires, improving the neatness within the cab. The driver sits on the reversing gear servo and the regulator servo is hidden at the front right hand side of the cab. A whistle from PPS Steam Services is fitted under the cab with the third channel of the radio operating it. This has required a modification to the steam turret body for an extra steam takeoff.
4. Tender.  This is a brass kit, supplied by GRS and has been soldered up as shown in the drawing above. The tender as supplied has the option of a cab (on the tender) which has been used to obtain the dimensions for the locomotive cab. There is plenty of space in the tender for the radio receiver, batteries and gas tank. There are two batteries, one for the radio receiver - four AA-cells (2400mAh) and one six AA-cell pack is also carried to run the loco headlamp. Cheddar Models have supplied their tank as fitted to Hercules, with one of their pressure regulator valves fitted in the pipeline. This is to give a longer duration than the standard R/H tank. In service, it has shown that a single fill of this tank has a duration of over 1 hour, thus there is a need to top the boiler water regularly.

The loco now has many hours running under its wheels on Southdown and local garden railways. It has successfully hauled good length trains and has been kept in steam for over an hour at a time. Some video was shot of the loco running - see here. The loco has since been painted and detailed.