Sommaire pour Issue 4754 de Model Engineer

Martin Evans can be contacted on the mobile number or email below and would be delighted to receive your contributions, in the form of items of correspondence, comment or articles. 07710-192953 MEeditor@mortons.co.uk ST ALBANS Over the last several years we have unfortunately lost most of our major national model engineering exhibitions. The last show run by this magazine, for example, was the 2016 show at the Brooklands Museum. Since then we have lost the Alexandra Palace and Harrogate/ Doncaster shows, which leaves rather sad gaps in the model engineer's diary. The Midlands show, this week, is currently the only regular national show still on the calendar. Fortunately, a number of clubs run their own shows and some of these are most impressive, matching the scale, even, of the big national…

SMEE A bit of background First of all, I'd like to shake the hand of the gentleman who built this steam plant (photo 1). It is without doubt one of the finest examples of this popular design that I have ever seen. It was the work of a Mr. L. J. Evans, in 1981, and unlike most model engine builders he was wise enough to put a neatly engraved makers plate onto the bedplate of his creation. If any reader can tell me where he built it and if he is still around, and even to introduce me to him four decades later, I'd be delighted to make his acquaintance. I wonder if he was familiar with full sized stationary engines as this one possesses a mechanical lubricator for the…

The redesigned transmission The main reduction gearbox had not suffered any damage. However, the redesign called for a change of bevel gears from 16T/24T reduction to 16T/32T ratio along with an output gear change from 20 teeth to 30 teeth. Please be aware that this range of reduction bevel gears is generally supplied as matched pairs. Due to an error in supply though, I had two 32T wheels spare. When the replacements came Technobots Ltd. told me to keep these wheels and not return them. A bit of careful measuring and trial with the newly supplied 16T gear showed that the compatibility was acceptable. It remained to be seen how this would work out in the initial trials with a completed locomotive. This change of ratio moved some of the…

Published bySeaforth, 2024 ISBN 978-1-0361-0769-7 144pp, hardback, £19.99 Something completely different! Heating, ventilation and refrigeration engineering have contributed enomously to human comfort and enjoyment but receive little attention from authors. As steamships increased in size problems of ventilating and heating passenger and crew spaces increased. With more passenger ships using tropical routes cooling became more important. Thermotank was an early air conditionaing system for ships, though the term ‘air conditioning’ wasn't coined untill years later. Electrical engineer Alexander Stewart thought of the idea working as a ship's engineer and then for the shipbuilders Thomson and Co. (later John Brown and Co.) at Clydebank. The Clyde then had over forty shipbuilding firms with a large share of the growing market for ocean liners which often travelled to tropical climes as well…

SMEE Those of you, who like me, were unconnected with coal mining and at the time were rather more concerned with building their own nascent careers to follow very closely the fortunes of that once important industry, could be forgiven for thinking that the miners’ strike of 1984-1985 marked the end of coal mining in Britain. Without intending any political comment - and these pages are not the place for such - I cannot but acknowledge the enormous impact that dispute had on the individuals and families on both sides and on the social and industrial landscape of the country and whose effects still echo today. So perhaps like me, to hear a description of a major development of an entirely new coal field in the last two decades of…

October 17-20 Midlands Model Engineering Exhibition Warwickshire Events Centre, See www.meridienneexhibitions.co.uk 18 Rochdale SMEE Annual General Meeting. Castleton Community Centre, 19:00. See www.facebook.com/RochdaleModelEngineers 20 Guildford MES Open day, 14:00-17:00. See www.gmes.org.uk 24 Sutton MEC Afternoon run from 13:00. Contact: Paul Harding, 0208 254 9749 26 Cardiff MES Steam up and family day at Heath Park, Cardiff. Contact: secretary@cardiffmes.co.uk 27 Westland and Yeovil MES Track running day 11:00. Contact: Michael Callaghan, 01935 473003 31 Guildford MES Open day, 10:00-13:00. See www.gmes.org.uk November 1 Rochdale SMEE Talk – ‘Re-building the Ellenroad Beam Engine’. Castleton Community Centre, 19:00. See www.facebook.com/RochdaleModelEngineers 2/3 Halesworth and District MES LOWMEX 2024, East Coast College, Lowestoft. See www.lowmex.co.uk 6 Bradford MES Meeting: Autumn Auction 19:30, St James’ Church, Baildon, BD17 6HH. Contact: Russ Coppin, 07815 048999. Note: Only…

Long ago, Somerset team Julie and Jon joined the local model engineers and started driving their Polly steam locomotive on the miniature railway in a local park, giving rides to the public a few times a month during the summer. Driving Polly in the park was fun but too much time was spent keeping it clean and in good working order. Maybe an electric locomotive could be a time saver. Critical eyes were cast over visiting electrics, inspiring thoughts about creating something robust and to high standards - a low maintenance design, to be more reliable and more efficient than the norm, using more up to date technology. This led to thinking of using modern brushless motors, rather than old style carbon brushed DC motors seen in other locomotives. With…

Some time in January 2021, during a telephone conversation with Diane, your Assistant Editor, who is also a member of the Northern Mill Engine Society, I mentioned that a beautiful, watercolour general arrangement drawing of a beam engine, intended for Egyptian Mill, Bolton, had come into the possession of the Bolton Steam Museum and was now gracing the museum wall (photo 1). The Museum was, at this time, temporarily closed to the public, of course. I sent Diane a photograph of the drawing and she asked me whether I was thinking of making a model of it. My answer was a definite ‘No!’ She then asked what it was about this engine that particularly appealed to me and suggested that I could, perhaps, make a model of just a part…

The Federation of Model Engineering Societies (formerly Southern Federation of Model Engineering Societies) promotes an annual Autumn Rally at various venues around the UK which this year was hosted by Nottingham SMEE. Nottingham SMEE shares a site with the Nottingham Transport Heritage Centre at Ruddington. Very well appointed with a fine clubhouse and well equipped workshop and machine shop, the Nottingham SMEE site features a dual gauge 3½ and 5 inch gauge raised alloy track some 2270ft long and a 7¼ inch ground level railway recently extended to about 3168ft. Fully signalled, the tracks are equipped with all appropriate facilities. Garden gauges are catered for with a 240ft gauge 1 track and a 16mm narrow gauge track currently under construction. With their popular venue enjoying a convenient location and excellent…

Goodness gracious me, how time flies! It seems barely a few weeks since I penned the previous episode, yet February is nearly over and fully five months have passed since last I sat before this keyboard to type a metaphorical hello. Now, before you accuse me of idleness, let me assure you that I have been anything but; the intervening time has been spent busily building walls, running wires and laying floors, partly for Jenny's new office in my vacated workshop and partly because the project inevitably expanded to encompass much of the rest of the basement. However, I am presently awaiting the arrival of our friendly building inspector who, having checked my work for code compliance and safety, will hopefully give me the thumbs-up to finish the job. Therefore,…

Frames Just to show how little information is needed by the laser, which gets what it needs from the digital shape, fig 4 shows a visual representation of the main frame plates. I've just given one dimension to help scope the size of the job and even this is not essential. Just think, also, of all the drawing office time saved by not dimensioning every feature on this drawing and how cluttered it would become. The frames need a bit offinishing before fitting and final machining of the horns. The laser cannot cut small holes, so those down to about 0.108 inch (2.75mm, 5BA tapping size) should be there, but for smaller ones the position will be accurately marked with a small cross. The frames general arrrangement with the side…

The cycle parts The cycle parts are simply a bicycle of 1914 with a sprung front fork but with no pedals. The run of tubes is broken at the bottom and the crankcases and engine plates complete the frame (photo 17). By WW1 this was commonly the case. There is no attempt to spring the rear wheel - rear suspension crept in in the 1930s and was not universal until 1970. The front ‘girder forks’ permitted a short range of motion but no damping. Friction damping could be incorporated into girder forks at the rear lower pivot but was not thought to be essential on lightweights. You can see the forks and their mechanism in photo 18. Most readers will realise that telescopic forks are now almost ubiquitous because they…

An algebraic digression Now for another digression. Earlier we saw that: By the same method we can show that: Likewise: There is a pattern here - the expression is always of this form: Note the second term on the right-hand side! Back to the plot – literally! So far we have looked at graphs in which velocity is plotted against time. However, we can also plot displacement against time. Suppose we have a body travelling at a varying speed, where the displacement varies as the square of the time, as shown for the first few values in table 4. If we plotted a graph of displacement against time, this would look like fig 4. Note that in this case the axes are not to the same scale as otherwise the…

Now that we have finished with the weighshaft brackets we can get on with the drag box. The people in charge of 76077 decided it needed a new one, so Andrew very kindly sent me some appropriate photographs of the very thing. I took some photos of it while it was still in place but that must have been at least fifteen years ago, so we are having a fresh start on this. Photograph 22 is one of the photos which I took, and which shows one of the boiler mounting pads. You must appreciate that I had a job finding the frames, let alone trying to take any photographs of the stretchers. Anyway, you will see that photo 23 does show a little more of the drag box. If…

Cheltenham SME The society has been in existence since 1938 and now has over 80 members. After so many years it was decided by the members that it was about time they had a clubhouse. This would also save the cost of hiring a room nearby for meetings. The society has been on the present site in Hatherly Lane since the 1960s when it was then owed by the Dowty engineering empire. Over the years it has been developed to cater for all areas of model engineering and has members from a wide area. The society also now owns the site. The building is a timber section type and came all the way from Holland. Member Bill Kaighin was the main lead for the project with members helping as well…

CLUB NEWS An interesting snippet heard on the radio one night concerned a mixing of Artificial Intelligence and speech synthesis. This impinges on an idea I had many years ago, whilst editor of Northern Heights Amateur Radio Society Newsletter, NHARS News. I suggested we may equip our radio relay system (repeater) with the voices of film stars, politicians, the hangman or a robot by changing a few components. At the time, computers weighed tons, lived in an air-conditioned room, with high security, physical or digital in the access. This is alive with possibilities, not least by appearing to have the speaking party saying something derogatory, risking a court appearance. I tried Voiceai but it is not available for Linux. However, Elevenlabs is free and works with Linux. In this issue:…