Co m p l e t i n g B r i d g e t

Interlude – the driving truck

My driving truck is a rather ad-hoc affair left over from a previous project (shown without roof in photo 48) I thought I might relate its history as an e ample of how things evolve As you will see from the picture it is a non-prototypical coach on a chassis with two bogies, each of two a les

In fact, this chassis was the first thing I made in my new hobby I had intended to build a CliShay locomotive as a first project as described in the book Building the CliShay by Robert Maynard (ISBN 0941653420). The Shay designs were used in USA, especially for logging where there were tight curves and rough track The CliShay had a central vertical boiler and a vertically mounted twocylinder steam engine driving a lay shaft Power was then transmitted to the wheel by chains between the lay shaft and the inner a le of each bogie and thence to the outer a les

My plan was to build this but, instead of the steam engine, to use an electric motor to drive the layshaft powered by two car batteries, one over each bogie I would then add a suitable made-up casing So, I completed the chassis according to the book I was then disappointed to discover that it would not work on my garden track which has some bends of 20ft radius Ironically for a Shay, the bends were too tight and as the bogie turned, the roller chain from the lay shaft ran up the side of the sprocket and jammed

I could not find a solution to this problem and had to abandon this chassis. Instead, I built a cruder chassis, the same si e, with two fi ed a les instead of bogies Clearly this solved the chain alignment issue – although much less elegant looking In fact, this locomotive (shown in photo 49) has served very well for the past five years and hauled many families happily around the track

So, the question arose - what to do with the spare chassis Having two bogies, I decided it would make a nice coach and I constructed a coach body out of plywood and painted it to be visually appealing I put foot platforms on and ensured the roof and supports were strong It was then pressed into service as a sit astride coach

Considering this chassis was design for a locomotive –considerably less weight than a person - it ran surprisingly well and sometimes had to cope with large loads (photo 50)

However, being intended for a locomotive, the chassis had no suspension at all To survive variations in the track the design used a ‘3 point’ system meaning that the weight was transferred into the bogies using two points on one bogie and a single point on the other – allowing the latter to rock to stay on during track perturbations This made the coach a bit unstable and prone to derailments In the end I retired it again and built two more sit-in trucks (see Riding Trolley, M E 4 586, May 11 2018, et seq )

This now brings us back to Bridget as I was looking for a ride on trolley that could take a large water tank and a car battery to power the pump

This big empty plywood bo was ideal I did make some corrections, moving to a four-point contact for the bogies and installing some firm springs to cope with track irregularities And so, the rest is history, as they say This has become my driving trolley and, so far, has risen to the job

Success at last

The coach, pressed into action as a driving truck, had plenty of empty space inside and I was able to install a 10 litre water tank, a small 12V car battery, the electric pump and a switch I found suitable high pressure hose and fittings Actually, the fittings were billed as ‘for pressure washer’ and were relatively cheap but good quality They have a very positive connection and disconnection and I have had no problems with them Of course, I had to rework the plumbing on the locomotive to feed the new supply in but it was a chance to reuse the water filter previously made redundant when I reworked the injector supply

Photographs 51 and 52 show the new plumbing

Finally, I was able to fire up the locomotive and bring it up to full pressure safely and, not long after that, take it out on the track for the first time Photograph 53 was taken on the first passenger run, slightly blurry as it’s taken from a video What you can’t see are my furrowed brows and white knuckles but all went well I have run the locomotive about half a dozen times during the summer and it has run well with even beat and enough power to get up the fairly sharp incline in part of my garden track So far nothing has ‘fallen off’

Concluding thoughts

It took me about five years to complete the locomotive from collecting the castings, frames and a few pieces that a previous builder had started until the first run I took up this wonderful hobby in 2015 with no prior e perience of metalwork beyond using a hacksaw (which, of course, I discovered I had been doing wrong) I did a lot of reading and, more by luck than judgement, bought a good size Harrison 10 lathe which has been wonderful and very forgiving I had never silver soldered anything and yet was able to make the boiler I had only a vague idea of what a milling machine was and yet I was able to make the rods and motion Somehow, I was able to muddle through and make this locomotive essentially from scratch The only two items I purchased as commercial parts were the injector and the cab pressure gauge (and of course a whole lot of nuts, bolts and rivets)

Of course, there are many superb engineers in the hobby who have completed apprenticeships and spent years in engineering companies and have skills and knowledge well beyond anything I could aspire to, but my observation is that, as a hobby, common sense, preparation, learning and practice are enough to make real progress with model engineering I sometimes read in Model Engineer people saying that our hobby will die away because young people are no longer learning the skills But I believe that the hobby will never die away so long as there are people who are fascinated by machinery and have a desire to solve problems and make things They will find the skills they need

Today, we have the good fortune to have equipment beyond that available even 20 years ago I have found digital measurement tools, and especially the DRO on the milling machine, to be essential to enable me to do accurate construction In past days accuracy was dependent on the skills of the machinist but these new tools allow progress even without the skills that take years to acquire E cept for rough items I never mark out from a ruler I don’t own a bottle of marking blue Some may bemoan the loss of these skills but there are plenty of problems to solve at every step and problem solving is the key to satisfaction

To be honest, I find I have little interest in driving the locomotive other than to give pleasure to others As I often say to people, “the novelty of driving round your garden on a train wears off pretty quickly” So, I have launched into a new construction project – larger and more challenging – and I look forward to telling you about it in future years.

As I close I would like to pay tribute to Model Engineer magazine and all the contributors I have found it enormously helpful to see how e perienced people approach problems and I have learned a great deal On top of that the more general articles are a jolly good read