Sommaire pour Issue 4739 de Model Engineer

Martin Evans can be contacted on the mobile number or email belowand would be delighted to receive your contributions, in the form of items of correspondence, comment or articles. 07710-192953 MEeditor@mortons.co.uk Bradford Challenge The Bradford Model Engineering Society invites you to join them in An Afternoon of Speed and Fun. Every year, club members build locomotives that are designed to compete in a time trial around the club's miniature raised track in Northcliffe Woods, Shipley. This has evolved into ‘The Bradford Challenge’ for which, as a local model engineering society/college/school, you are cordially invited to join. We believe that this challenge offers an excellent opportunity for your students/members to design and build a bespoke high-speed locomotive that will compete to see who can circumnavigate the track twice, in the shortest…

Continued from p.407 M.E.4738 March 8 To ensure maximum adhesion by the locomotive, its weight must be distributed to all of the driving wheels. In 1838 Joseph Harrison received a patent for his equalizing lever, which allowed the weight of the locomotive to be evenly distributed to the driving wheels. This compensating mechanism gave the evolving 4-4-0 the adhesion it needed to become a practical workhorse. Further development of the equalizing lever principle evolved into the design shown in the frame illustration. This system of springing must have been effective, as it was fitted to the New York Central's No. 999, a 4-4-0 locomotive known as the Queen of Speed, reported to run at over 80mph in 1893 between New York and Buffalo. The addition of a leading, non rigid,…

Continued from p.411 M.E.4738 March 8 Drain cocks The drain cock passages were all completed when the cylinder block was made and I had put off making the actual drain cocks until later. As already mentioned, the positioning of the lubricator had seriously interfered with the access to the LP drain cocks. The only answer was to fit suitable pipe unions into the LP cylinder drain holes and move the actual cocks to the left side of the engine where they could be mounted on column brackets. By the use of bronze elbows the HP cocks were still just workable (photos 199 to 204). The first cocks I made had a few of my own innovations but these weren't successful at all and managed to leak consistently. The next attempts…

Continued from p.390 M.E.4738 March 8 Before the finishing coats of paint were applied the oil and fuel injection systems were checked. I had made six different injectors before I managed to achieve a reasonable result but in the end I decided not to use any of them. I had spent weeks on the injectors and pump assembly and seemed to be going round in circles and not really achieving anything. The oil pump injects oil into the cylinder and, on my model, behind the reed valves to keep them wet and help the sealing. A decision was made to convert the oil port at the reed valves to the injection point for the fuel. As a two stoke petrol oil mixture was to be used this would go into…

Continued from p.397 M.E.4738 March 8 Making model engineering cool Take some time, and in your mind's eye picture the following… An elderly gentleman standing behind an old English lathe turning a simple shaft, wearing the necessary personal protective equipment, stylishly dressed in a lab coat or overall. Boring! Okay, let's imagine that same elderly gentleman elegantly discussing some of the more complex operations required to make his complex model or maybe steaming up the model and pulling loads of people around a miniature railway track with smiling faces and little kids screaming. Better, but this doesn't really say much about the building ethos of model engineering and the coolness factor is missing. Back to the Harley; the quintessential of cool. Now imagine a cool biker riding into shot on…

Well, today I am blessed with sufficient copy that I will be able to start CN 4740 without trying too hard to find subjects to discuss. Here's one, anyway. Visiting Sheffield Museums Friends gathering yesterday, I spoke to one of the staff on the subject of historic items not being noted, my particular point being with regard to model engineering and electronics and items which are passing in to history like electronic valves and hand tools being eschewed in favour of cheap machine tools. I noted that in far-flung parts of the world, a complete lack of communications became rapidly superseded by mobile phones without the intermediate step of copper wire joining the two. These artefacts are accepted, I suppose, as being powered by ‘magic’ by a remote civilisation. Similarly,…

There's an old Aussie tradition – when something goes wrong always blame somebody – somebody else! Before I name who is to blame for this article about the camshaft grinder shown (photo 1), let's go way back in time. We are standing in the main hall at the 2013 Model Engineer Exhibition when the PA announces ‘The winner of the gold medal for internal combustion engines goes to Gerard Dean from Melbourne, Australia’. Well, I was chesting out – another great Aussie tradition – a tradition that only lasted until the 19 piece crankshaft shattered a few minutes later. The word on the street at the time was that the Oxford Dictionary was going to use my predicament as the quintessential definition of the word embarrassment. Tail between my legs,…

Wherever you go in Britain, there is always something to be found that's fascinating to an engineer so when Mr. and Mrs. Backhouse ventured on an expedition to the Outer Hebrides they found plenty of interest. Apart from the workings of Harris Tweed looms - to be the subject of a future article - there was automotive and marine engineering to take us there and electrical engineering keeping us warm and cooking food. The Isle of Lewis has an example of a simple grain mill described as a Norse mill but probably originating long before Vikings came to the Hebrides (photo 1). It is located at Shawbost (Siabost bho Dheas in Gaelic) near the north west coast. It was used until the 1930s and was restored by a team of…

March 20 Bristol SMEE Talk: ‘Goliath, a model of a 1903 French tug boat’, Begbrook Social Club BS16 1HY, 19:30. Contact: secretary@bristolmodelengineers.co.uk 21 Warrington & District MES AGM. See www.wdmes.org.uk/events 22 Warrington & District MES Running day at the club track. See www.wdmes.org.uk/events 23 Bradford MES Spring Social Meeting, 19:30, Northcliff. Contact: Russ Coppin, 07815 048999. 23 Westland and Yeovil MES Track running day 11:00. Contact: Michael Callaghan, 01935 473003 25 Sutton MEC Afternoon run from 13:00. Contact: Paul Harding, 0208 254 9749 29 Warrington & District MES Running day at the club track. See www.wdmes.org.uk/events 30 Bradford MES Easter Bunny Event, 12:00 15:00, Northcliff. Contact: Russ Coppin, 07815 048999. 31 Plymouth Miniature Steam Public running and easter egg hunt, 14:00-16:30, Pendeen Crescent, Plymouth, PL6 6RE, Contact: Rob Hitchcock, 01822…

Sometimes it's quite strange how coincidences can lead to a model project. Sometime in the summer of 2014, I had the inspiration to look for live steam boilers at a large online auction house in the UK. After some searching I found a few locomotive boilers but, as I didn't want to bid much, I regularly lost the auctions. It has to be said that I already had four five inch steam locomotives at that time but I was really interested in starting something new. One Sunday evening I had the inspiration to search again. I found a vertical boiler intended for a quarry locomotive at a reasonable price that expired on Monday morning. I then decided on my pain threshold and bid on it. In the evening after work…

Continued from p.403 M.E.4738 March 8 Crosshead and slippers The crosshead assembly consists of a forked end that screws onto the piston rod, two slippers, a bush and a bolt. On first look at the plan, the forked end looks difficult to make (fig 2). It is small, has a 7BA thread that must be at 90 degrees to the hole for the bush, requires a slot for the connecting rod and the ends should be rounded. Tubal Cain gives us a solution for making the part using a lathe and vertical slide. He separates the forked end from the parent material before the part is completed and finishes it in a vice. I like the old maxim ‘keep the work as long as you can for as long as…