Sommaire pour Issue 4695 de Model Engineer

MARTIN EVANS Editor DIANE CARNEY Assistant Editor YVETTE GREEN Designer Model Tram Exhibition Saturday 20th and Sunday 21st August 2022 sees the return of the ever popular Model Tram, Trolleybus and Railway Exhibition at the National Tramway Museum, Crich Tramway Village, Crich, Derbyshire. A total of 10 layouts will be present at the Exhibition and two examples include: Whiteleaf Tramway Belgium had a very extensive tramway system of this type and the Buckinghamshire Garden Railway Society members are running Belgium Vicinal rolling stock, all of which is scratchbuilt. This is the largest assembly of Belgium G scale Vicinal rolling stock to be seen in the UK. The layout portrays an electric tramway that runs through the streets and then sets off through the countryside to serve surrounding villages. As not…

Introduction I had always felt that the large gap between direct drive and back gear on my lathe needed something doing about it and I contemplated the idea of having a two-speed motor instead of the single-speed motor that I had. Myford used to do this on one of their lathes, so there is a precedent for such things. When I moved house, I needed to build a new workshop and mount my 1934-built lathe on some suitable machinery mounts. Whilst making the mounts, I became somewhat irritated by the large gap between bottom direct speed and top back-gear speed, so I looked into what could be done. I could have built a second countershaft to provide a direct drive or a 2:1 reduction that would have filled the gaps…

This time a visit to Huddersfield for the Tolson Museum, an unpretentious but interesting council run local history collection for Kirklees. There are fascinating exhibits in the transport gallery with displays about local textile manufacturing and mining. Yorkshire winding engine displayed outside A Model Engineer reader helped save a steam engine from the Fieldhouse Brickworks near Huddersfield in the early 1950s (photo 1). As with many Yorkshire brickworks, coal and fire clay were extracted from the Coal Measures. (During the 1960s and 1970s my uncle, Edmund Sykes managed similar brickworks near Ainley Top between Elland and Huddersfield.) Quarrying and a tunnel into the hillside brought out fireclay with coal almost a by-product. The works made house bricks and firebricks though the market for the latter dwindled along with the demise…

Continued from p.47 M.E. 4693, 17 June 2022 If George Hawkes correctly assumed that the cylinder and air pump he saw at Low Moor Ironworks in July 1795 were intended for Murray’s own works then it is possible that the close of ground known as the Leckeys was leased by the partners before they formally purchased it in February 1796. Building may have already commenced in anticipation of possession becoming absolute which makes the advertisement that that appeared in the Leeds Mercury on the day after the deed was entered seem less precipitate: To IRON FOUNDERS. WANTED IMMEDIATELY, Two Sober, Steady and Active MEN, as GREEN SAND MOULDERS. Any Person answering the above Description will meet with constant Employ and good Wages, by applying to MURRAY & WOOD, HOLBECK, near…

July 15/16 Weeting Steam Rally Fengate Farm, Weeting, Norfolk. See www.weetingrally.co.uk 17 North Wilts MES Public Running, Coate Water Country Park, Swindon 11:00 – 17:00. Contact: Ken Parker, 07710 515507 20 Bristol SMEE Zoom meeting – ‘Fusion 360 Revisited’. Contact: secretary@bristolmodelengineers.co.uk 22-24 IMLEC 2022 Stoke Park, Guildford. See www.gmes.org.uk/events.htm 24 Bradford MES Open Day, Northcliff Railway 13:30 – 16:00. Contact: Russ Coppin, 07815 048999 24 Bristol SMEE Public running, Ashton Court Railway BS8 3PX noon – 17:00. Contact: secretary@bristolmodelengineers.co.uk 24 North Wilts MES Public Running, Coate Water Country Park, Swindon 11:00 – 17:00. Contact: Ken Parker, 07710 515507 29-31 Welland Steam Rally Woodside Farm, Welland. See wellandsteamrally.com 30 Cardiff Model Engineering Society Steam-up and Family Day, Heath Park, Cardiff. See www.cardiffmes.co.uk 30/31 Fareham and District SME Steam Railway Weekend, Club…

We knew that the ending of Covid rules would likely increase the number of visitors to this year’s Parklands Railway Week, at Hemsby in Norfolk. It has always taken place starting on the weekend of the late May Bank Holiday, continuing to the following Friday, but this year Royal Events moved the Monday Holiday to a Thursday and we were given an extra holiday on the Friday. We decided to stick to our original dates, so all our thoughts based on previous numbers attending were of little use. We need not have worried because in the event attendance was larger than we thought possible with some 41 locomotives attending during the week, with some locomotives we had seen before but many new attendees. The weather always plays a big part…

Continued from p.99 M.E. 4694, 1 July 2022 Air scoop The air scoop was fabricated in two parts - the main scoop body and the end block - as it would be extremely diffcult to produce the oblong channel with a flat bottom to the depth required. Producing the scoop in two parts will allow the oblong channel to be milled from both ends. First operation is to rough drill the channel end radii right through with a suitable drill (photo 74). Using two round plugs the scoop can be set square against a DTI ready for the machining of the channel, this operation will be repeated on the other end of the scoop (photo 75). Photo 76 shows the machining to half distance of the air scoop channel, while…

Continued from p.88 M.E. 4694, 1 July 2022 The switch contact Note, this switch isolates the battery and must be in the closed position before the engine will work. There are three parts, two posts and one arm, all made in brass (fig 15) and the posts are 13mm diameter x 25mm long. First hold the brass bar in the lathe, face the end and turn the outside shape. This is done to both ends of the bar because two are required. Next it is fitted in the square collet block and mounted in the mill vice for the slot to be machined. I first centred the 3mm wide slitting saw by eye and cut to a depth of 10mm (photo 77 and 78). The block was then turned 180…

Continued from p104 M.E. 4694, 1 July 2022 In my last instalment I described the development of the, now completed, marine-type boiler for William Spence. Before moving on, I thought it may be interesting to describe a feature of the prototype locomotive that will be replicated on my version. These locomotives were somewhat unique in that they were designed in such a way that the boiler could be removed from the frames for inspection and maintenance without disturbing much else, having the ability to be extracted from either one end or the other of the frames. Indeed, it may have been Samuel Geoghegan’s requirement to have a relatively easily removable boiler that lead to the use of a marine-type boiler, given that the marine-type boiler has no deep firebox or…

Continued from p.37 M.E. 4693, 17 June 2022 What is the correct colour and where does it go? The colours of the locomotive, and where the various colours go, should be defined by the prototypical engine – but straightaway we have problems. There were few colour photographs, even in the 1960s, and often we are reliant on what others have written or drawn since then to give us their thoughts. Although we have no idea of its colour, black and white photo 116 shows us that this engine, appearing here from the workshop, was most definitely shiny and not satin or matt finished. Oliver Cromwell is shown here outside Crewe works in February 1967, ready for official photographs after being the last steam locomotive rebuilt there. BR Standard Class 7…

Continued from p.28 M.E. 4693, 17 June 2022 The boiler clacks Many builders battle with getting boiler clacks (fig 27) to seal properly, with most of the problems traced back to a poorly seated ball on a non-round hole. Even with a keenly sharpened drill you will most certainly get a clover hole. To prevent this predicament, a similar approach to the snifting valve is followed, but this is one of the few times I’ll repeat the methodology to emphasise the machining steps. Starting with the part most likely to give issues (the coupling with the ball seat), start with the ball seat side; centre drill and drill with a smaller drill through full depth. Machine and thread the outside then flip the component around and machine the other side…

Continued from p.81 M.E. 4694, 1 July 2022 Boiler construction I don’t propose to give a blow-by-blow account of building a boiler as that has already been covered countless times in these pages. Instead I will provide photographs of the boiler at various stages of manufacture. My boiler was built for me by Paul Tompkins of Southern Boilers, whom I can recommend, both for quality and customer service. The boiler is, as you’d guess, mainly to Don Young’s design but is stronger and has a higher working pressure of 100 psi versus Don’s recommended 90 psi. The shell is a work of art, with the parallel barrel blending in nicely with the taper and having no step thanks to TIG welding and it really does look like the full-size article…

Continued from p.77 M.E. 4694, 1 July 2022 Block Diagram Figure 7 is the block diagram that corresponds to the schematic diagram. With our mental picture of the motion of the pendulum and the order of the opto signal inputs (fig 7), we may put the block diagram into operation. Pull the bob to the left of the centerline; then push it to the right and as the flag passes through the OFF opto, its output signal goes from low to high and back to low. Reading the block diagram to the right, at Node No. 1 the signal splits into two directions. Taking the vertical branch, the OFF signal goes to the Reset terminal of the MIN(IMUM) flip-flop resetting it and its notQ output is now high. Following the…

Stan was born in London in 1925 and trained as an engineer with an interest in communication equipment. When old enough he signed up to join the forces and passed his medical, only to have his application cancelled because his engineering experience classed him as a Reserved Occupation. During the war, Stan would be provided with a set of drawings and sent to a factory outside normal working hours, to ‘borrow’ their machines and make equipment to support the forces. He was responsible for turning parts and grinding crystals for communication equipment. At the time he was not told why he was making these parts and later discovered that some may have been destined for Bletchley Park while others were for use in radar vans. This work was usually at…