An Engineer in Model Engineering

Talk – Tuesday 8th March 2016, ‘An Engineer in Model Engineering’
Ray Parsons
Ray gave his talk at short notice to fill a gap created because an external speaker had had to postpone his talk. Ray explained that, shortly after he joined the RCEA in the 1990s, he had offered to give a talk on boiler water treatment, but that was deemed too specialised. Instead, he decided to base his talk on his hobby of model engineering. While his interest – building miniature locomotives – was quite specialised, by covering the activities of the Beech Hurst Park Miniature Railway he could address a range of engineering disciplines. Today’s talk is based on the material he used in the 1990s.
The Beech Hurst railway is operated by the Sussex Miniature Locomotive Society and can run 5” and 3 1⁄2” gauge locomotives on a raised track in a public park. The engines are owned by individual members, while the rest of the rolling stock belongs to the club. The track is 2193ft long with a maximum gradient of 1:100; the station is at the bottom of the hill. It was first opened in 1954 and extended in 1972. Ray has been a member since 1959. Ray pointed out that the railway at the back of Field Place is similar to that at Beech Hurst Park – the Worthing club borrowed their drawings and jigs!
The first engine that Ray built was a 5” gauge, 11/16” to 1’ scale LBSCR Atlantic (Henry). The cylinders were made of gunmetal and the boiler from silver soldered copper, operating at 100psi. The engine ran for 11 years before a boiler tube holed. The driver has to sit behind the tender and reach over it to operate the controls. The skill is in moving the engine away from a standstill without spinning the wheels. On one occasion, Ray’s daughter asked if she could borrow his engine to use as part of a display at their local library. Ray loaded it onto a trolley and his daughter was towing it from their house down to the library with a friend when they met a lady with a dog who was standing watching them in a slightly supercilious way. As they passed, his daughter commented “Madam, everyone has a dog.”
Ray planned to build a second, smaller engine (Ajax) which would be lighter and easier to handle, and would avoid having to lean over the tender. He started work – the supplier provides some castings (which then need machining) but everything else has to be made from sheet or bar material. The engines
use radiant superheaters to improve efficiency, but they aren’t easy to manufacture. Ray used a combination of cutting threaded holes in the block ends – the tubes were graunched into the block for mechanical fit and Sifbronzed to the block as well. The process of building an engine is very long job and Ray didn’t finish it, selling it to a colleague in due course.
Ray discussed the principles of scale modelling. In the UK, the most common scales are 11/16” to 1’ and 11⁄8 to 1’. The latter scale gives a bigger engine which is better able to cope with the overload which results when hauling passengers. Ray’s second engine, a Black Prince Stanier LMS Class 5 (Black 5) is a true 11⁄8 ” to 1’ 5” gauge model. Martin Evans came up with the idea of using a hybrid scale: 11/16” for the length and height, with 11⁄8 ” for the width, so allowing for heavier bearings to be installed. The Americans use 1”: 1’, which makes calculations easier, but requires a 43⁄4” wide track which is incompatible with British models. Another alternative is to model narrow gauge engines, which allows a smaller engine to pull the rolling stock.
One unusual request that the club received was to provide a wedding train! Ray duly decked out Black 5 with wedding ribbons and carried the wedding party round the track – quite a challenge for some of the ladies in their formal dresses!
Occasionally, engines will malfunction while on the track, and the club has a facility that allows members to remove the wheels and change bearings etc as required – Ray had to do this once with Black 5 after a crank pin failed.
The track comprises 3 rails, so that either 31⁄2”or 5” gauge engines can be operated. They are set on wooden sleepers supported by concrete pillars. The rails are made of aluminium to minimise wear on the wheels, and have to be replaced every 6 years – the replacement is
managed as a rolling programme. There are two types of points which give access to the sidings: the first, a pneumatic point, requires the track to be lifted and moved across to change direction while the second is a rotary point, as used by the Ballybunion Railway (an Irish monorail dating back to 1888) – it is often mistaken for a turntable. There is an engine turntable, but it is a length of track supported by a central pillar which allows that section to be rotated.
When the track was being extended, the Council (who own the
ground) asked that a section be run through a tunnel so that the
land above could be used for greenhouses. This presented a
considerable challenge, but the club members rose to it. One of
them worked for JCB and arranged for a digger to be provided
for a fortnight’s ‘demonstration’. The plan was to produce a
‘cut and fill’ tunnel 175’ long and 7’x7’ in cross section (the
cross sectional dimensions were chosen so that, even if
passengers tried to stand up, or hold their arms out, they
wouldn’t hit the walls). They became expert in producing
wooden shuttering and installing reinforced concrete (with a
little advice from a contractor building a local flyover). The
ends of the tunnel were faced with brickwork to look good.
The Council were so impressed with the result that they asked
if the club could replace a nearby footbridge. The club agreed,
and the request turned out to be well timed: when someone pushed the bridge to assess its solidity, it fell over!
The club uses fully automatic 3 aspect signalling, with monitoring facilities in the club house and the station building: when a train is on a section of track, it shorts and the signal goes to red; a yellow indicates that there is a train on the next section, and a green that the track ahead is clear.
One of Ray’s friends in the modelling world is Allan Stone. One day Allan contacted Ray and asked if he would help with an important visit from the East Midlands Area Board, who wanted to visit Allan’s house to inspect a heat pump that he had installed. Allan thought it would be good to give them the bonus of a ride on the ground level railway that he had in his back garden. Allan would meet the visitors for initial discussions at his office in Boston, then one of his colleagues would drive them out to Allan’s house through the centre of Boston while Allan nipped round the bypass (a much quicker route) to greet them on arrival. Ray willingly agreed to this; on the day, he had warmed up the engine and was setting off on a circuit of the track when he found that the garden gate had been closed across the track, and the visitors’ cars were arriving. There
was no sign of Allan! Ray managed to stop the train in time and then went to greet the visitors. He managed to keep them happy – especially the EMAB Chief Engineer, who he allowed to drive the train! Allan eventually appeared: he hadn’t realised that there were road works on the bypass that had caused chaos. He was able to give the required demonstration of his heat pump, and Ray thought that he had managed a difficult situation pretty well. It wasn’t until the visitors had left that Allan’s wife Wynn pointed out that she had taken great trouble to have all her best crockery set out in the hall to greet the visitors with tea on arrival. Ray had hijacked the visitors and, eventually, brought them in through the back door, upsetting her carefully laid plans!
In conclusion, Ray warned his audience that the photographs were of Beech Hurst Park in the 1990s. If you go there today, you are much more likely to see battery-electric engines than the lovingly crafted steam miniatures that he and his colleagues made.

Perry Eastaugh