Club evening March 2025.
Guy stood in for our chairman this evening. He reported that he had met with the new owners of the PP and it looks positive, but there is a need for more discussion.
The proposed club outing is for the 16th. June and to the Severn Valley Railway who are also having a '40s weekend. The cost to be announced but each club member+1 will have the coach paid for from club funds.
Guy handed over to Andrew to talk to us about the construction of his Lantern Clock. This kind of clock has a very early history going back to 1680 and this model just has the hour hand and strikes on the hour. However, Andrew told us that the mechanism is not that accurate especially by today’s standards and 10 or 15 minutes a day could be gained or lost.
The mechanism is of standard design with a suspended weight powering the hour hand and the rest of the mechanism regulating the time the weight takes to fall. The pinions and wheels making up the gear train (pinions 12 teeth or less) leading up to a contrate wheel which takes the mechanism through a 90degree movement to the crown wheel where the pendulum allows the crown wheel to move one tooth at a time via the escapement.
Andrew took us through his methods. Brass has become a very dear medium and Andrew considered how the basic construction should go to have the least amount of wastage. Andrew was making 3 clocks all the same for each of his sons. Pillars were made in part and screwed together rather than machined down from the solid. The mechanism supports were cut out and as Andrew said were not a ‘machine’ fit but loosely held in place.
The machining of the gears involved some extremely small 5 tooth pinions and several were discarded in the process. The shape of the teeth was convolute and not the involute normally associated with gearboxes etc. There were several different and larger ones to make and each came along with it’s own problem, the contrate gear had to be machined from the solid, I think Andrew said initially superglued to a faceplate but later bolted on as well. The crown wheel also needed careful attention and balancing as this was the timing of the clock and regulated by the pendulum.
The audience were intrigued by Andrew’s methods and several questions were asked during Andrew’s talk. Finally all was assembled and no doubt the pendulum adjusted for timing. A working clock rattles when shaken as there is little engineering need for close fitting gears and accurate bearings. In use the clock would be mounted on a high shelf with the weight allowed to fall below.
The finished product on show is highly polished with not a blemish showing, the bell on top sounding the hours. We had further questions and then the camera was adjusted to show detail of the clock and tools used during construction. Andrew was thanked for his talk with a round of applause. Additional thanks to Rob for setting up the camera and the IT side of the evening.
Rob has produced a video of Andrew's talk and you can view it on YouTube HERE
We had a break and many were intrigued by the separate racing car layouts.
Our Master of Ceremonies waited patiently for the audience’s / class attention, we were let down by one class member who had to be reminded to “pay attention”. Jim then started his talk about the history and the various companies involved in producing model racing cars. Jim was very concerned about the audience as far as carelessness and being ‘careful’ mainly directed at his model cars with wings. He was not keen that these should be raced either.
He emphasised the points of being careful with his very large collection and driving with this in mind. Many of us were now firmly back in school at the age of 13, a dangerous age, when instruction is not taken in lightly. We would be allowed to play afterwards but should remember to be ‘careful’, oft repeated and we felt that Jim would and did miss nothing.
The cars were to run only on the tracks they were put on as there were several types of mechanisms involved. The basic system we all know and remember now also had a magnet to hold the cars better on the track. There were ways of crossing to the other track, and here I had to ask for more information later. Quite clearly, I had not been paying proper attention when this was first explained!
The latest system had multiple cars on the tracks as each had a decoder and picks up AC from the track and here the individual car is controlled and not the applied track voltage.
Jim also went through the decorative accessories available, although Jim suggested that in the main they took the operator away from the job in hand of racing and could even block the view. Then there were the technical accessories like the lap counter and time disciplines for infringements while racing.
The various spares of power pick-ups and the options, the different motors, some tuned, but also showing the development of the old ex-model railway open frame motors to the can motors now in use. And of course, the rubber tyres and traction they afford. Jim had been assisted by his brother Chris although it came across that it was an act of filial affection rather than of a sibling relationship. Chris accepted all in good part and we all enjoyed the rather unique presentation.
Supervision of the racing was done after the talk but eventually the tracks had to be picked up and the cars re-boxed. It had been a good evening and unusual as there were no ‘detentions’ handed out although the occasional ‘strong look’ had to be used. Jim and Chris were not formally thanked but they had led a fun evening to finish with and it was appreciated by all who took part.
Seriously though thank you very much to the speakers and the time they put into making it another successful club evening. We had 3 guests one of whom, John, will be speaking to us in July on CNC machining.
The chair 'puter-outers' did us proud enabling an early start and thanks as always to Jack and Neil for the tea and biscuits, and I did like the coconut ones, provided just when needed. We also did a double check on turning off lights etc.
Roy Verden 14/03/2025