Sommaire pour August 2025 de Model Engineer & Workshop

When I first bought my lathe, I was just an enthusiastic amateur who knew I wanted one, but not totally sure what I was going to use it for. It was about that time I found Model Engineers’ Workshop magazine, along with other classic machining books, and started to learn about all the possible uses you can put them to, not just turning a shaft or making a bush. As I learnt more, I wanted to modify the lathe, adding things 920 style lathes were not fitted with from the factory. Starting with converting the tailstock to lever operation to make drilling more efficient, by not having to pick up, put down or search for the spanner to loosen or tighten the clamp nut. Then moving to the headstock with…

As a quick recap from last time, I explained how thin, small or otherwise fiddly workpieces can be successfully held for light lathe operations by supergluing them to a faced-off piece of aluminium bar held in the lathe chuck. MILLING MACHINE APPLICATIONS Most milling jobs are held on the mill table either by a combination of bolts and clamps or by using a machine vice. There are of course many variations on this theme and other methods too. As with lathe work, there are sometimes milling jobs that present a workholding challenge. For example, thin work or work needing to be machined on all edges. The normal solution to such a job is to use several clamps, removing and replacing them in sequence to allow the cutter to reach all…

The low-pressure cylinder casting, fig. 46, was in gun metal and, unlike a lot of the other castings for this engine, had reasonably generous machining allowances. Generous, that is, except for the thickness of the base and the height from that to where the cylinder centreline had to be. What the casting didn't have was any immediately obvious surface to choose as a starting point for machining and getting it to its final size was going to be a process of successive approximations. Fortunately, the cored space for the cylinder bore was very smooth, straight and aligned very close to where the bore had to end up. With only a little filing the cored surface was made smooth enough to allow it to be used as the first reference surface…

THERMOSETS All the information in the first half of this article refers to the fusible polymers, ones that can be and are, frequently melted and then moulded or extruded but there are polymeric materials in widespread use that are moulded as precursors and then allowed to polymerise in the mould. They produce materials that at the molecular level are made up of 3D networks that cannot be melted. Your domestic electrical fittings are almost invariably made from thermosets. Obviously, a good safety choice because they don’t melt and run if they enclose an electrical overheat or fire. Thermosets have a long history; Bakelite, a phenol-formaldehyde polymer, appeared before WW1. Some of the pictures of chemical workers stirring huge smoking pots of toxic reagents heated on coal-fired cookers wreathed in fumes…

I have always been interested in miniature machine tools, maybe the very best were those built by Barry Jordan exhibited some years ago. I noticed recently that the Bridgeport miller and lathe he built was up for auction, but these will have been sold long before this article gets into print. When Stuart Models introduced their range of machine tool casting sets I bought them as they came out and have completed them all. I also had an example of the steam hammer from way back which is an old favourite since the castings business was part of Stuart Turner. Photograph 2 shows the wood turning lathe, and photo 3 the metal turning lathe, which looks a bit bare without a workpiece in place. Photograph 4 shows the shaper, also…

I had a false start because I made an error; I was told by some well-meaning person that the valve gear and cylinders of a BR Standard Class 4 were the same as my 4MT but sadly, I now realise, they are not. They are, in fact, the same as the Standard 3MT, 77000 Class and the 2-6-2 Class 3 tank loco which, fortunately, Mike Jack in New Zealand is well on with building. He has already had the cylinders cast but they are exquisite lost wax casings. I have had to spend a lot of time redrawing the cylinders, figs 64 and 65. However, the description will be just the same, fortunately. Mike is going to supply them to The Steam Workshop so many thanks to him for that.…

Quite a few years ago, I went to get rid of an old battery drill. As usual I first dismantled it to see what it’s made of. Despite the cheap exterior it had a very well-made electric motor and chuck assembly. Much too nice to throw away, so, into the ‘sometime’ bin it went. On a number of occasions recently I needed to drill holes in a work piece, ideally whilst it was still in the lathe chuck and typically on a pitch circle diameter. The solution was to mount a drill on the tool post, much as a grinding spindle would be fitted. It proved to be perfect time to utilise the ex-drill motor and chuck. The photos show the result. Photograph 1 shows it in work position and…

Reading is a pastime that compliments all hobbies, gives direction and sparks ideas. I don’t have an idiot box and yes, we do have power here in Africa; sometimes. So the nights out of the workshop are spent reading arbitrary technical treaties. Unfortunately, casting is one of the very few subjects where reading up on the topic results in diminishing returns rather quickly. The older books (the ones I prefer, written in the 1900s) give loads of examples and casting recipes but very little information on riser and ingate design. The newer (hobby and industrial) books tell you to buy stuff from suppliers, items that can be found in the local grocer at exorbitant prices. Literature relating to the subject in academia is useless to say the least; most foundrymen…

This June the 2025 IMLEC was hosted by the Fareham Society of Model Engineers in Hampshire. Regular readers of Model Engineer will be familiar with the annual report, but since our combination with Model Engineers’ Workshop, many readers may be unfamiliar with the event and its significance. I have attended an IMLEC once before, at Ilshaw Heath in 2018, however that was just for an afternoon. IMLEC takes place over three days and I was at the magnificent Titcham site, photo 2, on Saturday and Sunday, as ME&W sponsors the event and I was presenting the prizes to the winners. My intention here is to explain the competition rather than present the result, which will be in our next issue. So, what is the competition about, you may ask? Model engineers…

From time to time, I trawl the YouTube videos out of interest to see how things have been made, repaired, re-purposed or created by those who earn their living doing that kind of work. This is a second gathering of clever ideas and short cuts that save these people unnecessary effort or time in getting things done. I have also added a few thoughts and observations of my own that I have found helpful and included an unusual workshop experience from my last industrial employment which might make interesting reading. A SHORT COLLECTION FROM YOUTUBE MATERIAL The first of these comes from Kurtis Allen, owner and CEO of Cutting Edge Engineering (CEE) in Queensland Australia. They do a lot of repairs and rebuild work for the mining and earth moving…

Time for the big one; the boiler. This is a job that uses heat, hammers and nasty fluxes - and forget about getting parts accurate to a thou’ or two (except for machined components). It’s good fun. The design is to what I will call the ‘enhanced Rob Roy boiler code’ witha dash of LBSC and is targeted for readers in the UK. Those of you elsewhere in the world or working to other codes will need to make your own adjustments. The Australian code is often mentioned here but most of the rules are mandatory and it is impossible to manufacture to this code in the UK because it specifies use of materials which are not available here, such as cadmium bearing solders, or to specifications which are not…

The cross-section of the slot needed to be part of a circle to allow a ground shaft to be accurately located in the slot. I was hesitant to buy a full-radius end mill or a convex radius cutter for horizontal milling, that might only be used once for a 15-minute operation. While the design of the tilting table later evolved to no longer require the radiused slot, I had already devised a method to produce an approximation of the slot – using ‘standard’ end mills. Hopefully someone else can also benefit from this method. Photograph 1 shows a sample aluminium plate with two grooves milled in it to fit two ground shafts. Being aware that mathematical exercises tend to discourage some of us, I will do my best to keep…