Indholdsfortegnelse for April 2025 i Model Engineer & Workshop

These are a few notes on the making of a small working oil can, photo 1, which was not only fun to make but also proved a talking point for quite a few model engineers later on. Many years ago I had made a small model oil can for my 5” gauge De Winton vertical boiler loco. This was bolted onto the toolbox lid. It did not contain oil, but the lever was spring-loaded, so it did look pretty realistic. Of course the usual club wags had to press the lever up and down, then announce to all that it did not work. With this in mind I thought a working one would be more of a challenge. The later version, figs 1 and 2, was similar as it had…

A NEW WHEEL LATHE FOR NORTHERN TRAINS A wheel lathe named Tina has been unveiled as the latest weapon in the battle to ensure the region's train wheels "keep on turning". The machine, which reshapes and balances a train's wheels following natural wear and tear in service, reduces the impact of the train on the track and makes journeys smoother for customers. It has been installed at Allerton TrainCare Centre in Merseyside as part of an £8.9m project between Network Rail and Northern. Nicknamed 'Tina' by the train operator's engineers, she replaces an old wheel lathe called 'Charlotte' and has doubled the wheel-lathing capacity of the depot. In total, 1,600 tonnes of soil, stone and concrete were excavated to accommodate her and 184 tonnes of concrete was used to set…

For Chris Barham the construction of his 4-inch Garrett Agricultural Engine can hardly be described as a rushed job as the project began in 1997 and he is still tinkering with the engine today, photo 1. Chris is an experienced engineer having served an apprenticeship as a marine fitter and turner and he then worked in shipyards and power stations and finally working at the Thames Barrier. In 1997 he turned his attention to the construction of a 4-inch scale Garrett having obtained the drawings prepared by Bill Newcombe. The decision was taken to prepare his workshop first, so the old original garage was replaced by two precast garages where the work started. These were later replaced by a large, block built, workshop with a 415 volt electricity supply. This…

Drill bits are brittle tools and have a high length to breadth ratio. Smaller drill bits are particularly at risk of flexing and snapping under load. This is why it is so important for the drill bit to be aligned central to the axis of rotation, so that the load is distributed along the length of the tool. Turning the tailstock hand wheel applies a compression force along the drill bit. The size of the rotational force (torque, lb/ft) applied to the tailstock hand wheel determines this force which is one determinant of the feed rate. Other determinants include the geometry and sharpness of the tool. When all of these forces are not well balanced, the likelihood of experiencing problems increases. One example is applying too much pressure to advance…

The water tanks, cab and bunker are all 0.8mm brass (photo 12). I cheated here. I had created CAD files for my own engine years ago and had them laser cut. There are about 3000 plus 5/64 inch rivets all up - 'pimples everywhere', as LBSC would say - and I didn't relish drilling them all and trying to keep fairly straight lines. I made several bending jigs to do the corners. This was done in an hydraulic press with formers and jigs, photo 13. Inside the tanks is a framework of ¼ × ¼ brass angle. I machined my own angle out of 3/8 inch brass bar. The corner angle frame parts were NC machined. All this is both riveted with the 5/64 inch copper rivets and sealed using…

As noted above, an identical drawing was used by Francis Trevithick as his Plate 5, in the Life, Vol. I, facing page 185. There can be little doubt about the fact that the lithographed engraving by the London engraver Kell Brothers is taken directly from the A well-executed perspective view (by modern drafting nomenclature the drawing is made up of elevations, sections and plan views rather than an orthogonal perspective) and has been annotated for a key description. Francis Trevithick must have been aware that this drawing was one of three as he lists all of them in quoting the Gateshead Observer article. He does not discuss the other two drawings anywhere else in his tome. These latter two drawings are quite different from the wash drawing in character, being…

Last time I machined the first gear, by supergluing it to a special mandrel. The whole process is then repeated for the next gear, it only being necessary to lightly re-face the mandrel to remove the glue residue and confirm flatness. For reference, photo 10 shows an alternative method to bore a gear after cutting, and photo 11 is a small gear blank being readied for machining. This is a suitable workholding method for any thin workpiece, disc-shaped or otherwise, and especially where there is no bore by which to hold the work. Although other methods are possible, this is a quick and easy way to machine a disc to a precise thickness and diameter, or to machine any suitable thin part to the required thickness. This is also an…

I can’t remember a time when I was not making models of some sort or other. I grew up with Meccano (mostly passed down from my Dad) and Lego, and graduated to Airfix kits as soon as I could be trusted with a modelling knife. In my childhood, Dad had the entire ‘middle room’ as a workshop and it was full of radio control aeroplanes, boats and accessories. My equivalent of Proust’s madeleines is the smell of nitrocellulose dope and castor oil. It was impossible not to become modeller in such an environment, and my interests expanded to model boats, and I still have a crude balsawood Clyde Puffer that I remember proudly taking to Junior school to give a talk in front of my classmates, photo 1. Another talk…

Readers! We want to hear from you! Drop us a line sharing your advice, questions or opinions. Why not send us a picture of your latest workshop creation, or that strange tool you found in a boot sale? Email your contributions to meweditor@mortons.co.uk. THE NEW LOOK MAGAZINE Dear Neil, the latest copy of the new ME & W just dropped through the letterbox and, oh dear, all my worst fears were confirmed - the cover had a couple of models of 150-year-old locos, probably built to pre-war plans as used by literally generations of model engineers. My heart sank - this was the reason I stopped reading ME years ago when I found out MEW (issue 48) existed. Much more useful for a beginner in model engineering although my skills…

I am currently refurbishing an old electricity generator, driven by an Aspera engine, which should, hopefully, be finished by the time you read this. The age of the generator unit is unknown, but it is in fair condition despite needing some refurbishment and tender loving care. The exhaust muffler and fasteners were highly corroded and required replacement. When removing the bolts, one bolt sheared off leaving the threaded portion stuck in the exhaust flange, photo 1, not an unusual workshop problem. Corrosion of this bolt was particularly severe, as the threaded hole was on the outside of the engine and exposed to the elements, unlike the remaining three holes. I was worried that the use of a stud extractor would fail - it could fracture in place, making the problem…

We now come on to the expansion links, fig. 48 and photo 105, but once again these came with my pack of valve gear from Mike Jack. I had to drill all the oil holes again and make the oil pots. The holes for fixing the two parts together were drilled before the curved slots were machined. The return cranks, fig. 49, and the union links, fig. 50, were also supplied by Mike and these are shown in photos 106 and 107. I then made the pair of yokes, fig. 51, for the valve rods. They were cut out of a piece of ½ inch square BMS bar and I cut the slot first. The bar needs to be slimmed down to 7/16 inch, either on the milling machine or…