A commercially available 120 amp controller was selected to handle the electrical aspect. Bought, rather than built, principally because of the popularity of robot-wars and similar events, commercially ready-made units are now a cheaper alternative to buying the necessary components and avoid burnt fingers with the soldering iron!

From a previous project, a pair of 270 degree panel meters had been waiting for a good home for some time and filled out the drivers console nicely, although the max. reading on the ammeter of 150 amps is probably a little optimistic !

Although the original concept was to build a practical and above all usable loco rather than an accurate model, the inclusion of vacuum (or rather more accurately termed - equilibrium) brakes could not be missed.

A commercially available pump fitted under the canopy generates an adequate vacuum in a matter of a few seconds to fully activate the system. The brake cylinder is mounted to the rear centrally in the frames, and acts through a lever, shaft and then as per the prototype, the brake hanger pull rods on each side. The driver's panel was thus further expanded to accommodate the brake valve and vacuum gauge.

'JALEX' was conceived almost two years ago, the object being to construct a simple locomotive suitable for the three children in the family to operate (five, six and forty-six years old respectively !), in 7¼" gauge.

After much deliberation over portability, track availability, build difficulty and Jamie's "something with coupling rods please", a battery powered B.R. class '08' 0-6-0 shunter was decided upon.

The frames and stretchers were laser cut from 8mm mild steel plate, tidied up by the 'older process' of file and elbow grease. These were then clamped square and arc-welded to form an extremely solid chassis. Traditional cast iron wheels were turned and pressed onto mild steel axles. The drive is provided by four 24 volt motors which are hung in pairs from the front and rear axles similar in style to the prototype.

Power is transferred to both axles through a six to one reduction pinion and gear train. The motor carrier plates and horn blocks are all "bushed" with oilite bronze bearings. The fly cranks were "externally" CNC machined and retained by way of a pair of "dog" pointed socket set screws run right through the cranks, and located into milled recesses within the axles. The coupling rods were again laser cut, finished by hand and fitted with bronze bushes.

In practice the loco rarely draws more than twenty five amps. Encouraged by the prospect of having a full drivers panel a matching speedometer was ordered. This is of course nothing more than a ammeter and is fed electrically by a small electric motor sprung mounted inside the frames and driven via a hard rubber wheel resting against one of the centre driving wheels, acting as a dynamo.

To ensure all the safety aspects were covered, an additional key operated master switch and sixty amp inline GEC power fuse were incorporated.

The canopy is a ready formed glass fibre moulding and provides an economical basis for completing the loco, whilst allowing for considerable detailing to be added without increasing the already considerable weight. Presently 'JALEX' sports air horns, a full set of running lamps, ladders, steps and a full set of handrails.

After a full charge the two 12 volt leisure batteries provide a full day's running, amounting to several miles, without any noticeable depreciation in performance.

Well it keeps the kids amused . . .