Tabla de contenidos para January 2023 en Model Engineer & Workshop

Bovington Tank Museum I celebrated my birthday in November and to mark the occasion a few days later my two brothers took me for a day out at the Bovington Tank Museum in Dorset. We had been before, but that time my youngest brother was literally a babe in arms! All three of use share a fascination with armoured vehicles since childhoods filled with model kits. It was remarkable to see so many of the machines we knew so much about for real, many of them being among the last few of their kind. The whole story of tanks is covered, from Little Willy, following their development up to the present day. Exhibits include Tiger 131, the last working Tiger Tank. We had hoped to see the Sherman that also…

GEOMETER describes some types and their uses BEGINNERS WORKSHOP These articles by Geometer (Ian Bradley) were written about half a century ago. While they contain much good advice, they also contain references to things that may be out of date or describe practices or materials that we would not use today either because much better ways are available of for safety reasons. These articles are offered fortheir historic interest and because they may inspire more modern approaches as well as reminding us how our hobby was practiced in the past. IN ITS VARIOUS FORMS, the valve is an essentia] part of engines, pumps and pressure, systems depending for their function on the retention or flow of gases and fluids-air, water, petrol, oil, etc. The simple valve works automatically from the…

I usually make at least one spare Even when we have a plan for how we are going to make a part for a model, we sometimes make a mistake, and the part is spoilt. Sometimes we don't make a mistake at all, but something happens over which we have little or no control. Examples of this would include: coming across air bubbles in a casting, a workpiece fracturing when it is bent in the fly press, a silver soldered joint which is sound but just looks horrid, a tap which breaks and cannot easily be removed This is particularly frustrating when we are right at the end of a long series of machining processes. Photograph 1 shows an axle box which was spoilt on the very last pass of…

MARKET LEADER IN LARGE SCALE, READY-TO -RUN, LIVE STEAM 25 MODELS ONLY OVER 75% ALREADY SOLD! The LNER A3 The world famous "Flying Scotsman" is probably the name that most readily comes to mind out of the 78 A3's that saw service on Britain's railways. All locomotives received double chimneys by 1960 and subsequently most were fitted with German style "trough" smoke deflectors following complaints from drivers in respect to poor visibility. 4472 was the first steam locomotive to be officially recorded at 100 mph. The A3's saw service over most parts of the LNER system. The final locomotive, 60052 was withdrawn in 1966. Before the war the A3's were painted in LNER green livery, but carried unlined black 1939-45. They were re-painted in LNER green following the war, A…

There is nothing new under the sun, and I quite expect someone will be along to say his granny had one in 1922. Anyway, this describes a device I evolved, and how it can reduce the nuisance of changing the head height of a round column mill/drill. Most vertical spindle milling machine owners will be familiar with the edge finder in one or another shape or form. Photograph 1 shows (A) a split cylinder finder, and (B) a Huffam (a similar function is usually included in a wiggler set). The upper shaft is gripped in the chuck or collet, the spindle set rotating, and the displaceable lower indicator or sensing part is used to find the position of an edge. It is brought lightly into contact, the initial "touch” setting…

The riveting tool from issues 318 320 is shown in photo 1. To make the riveting heads, the hexagon key that was left over from the riveting tool cutters would be the donor for the two new riveting heads or possible more than two if there were enough key left after cutting them, photo 2 shows the last part of the key. The dimensions were taken from the original riveter i.e. length and groove size, then the key was cut to a little over the length required this is because it was cut freehand and not necessarily very square, the squaring up will be done when the hexagon is in the lathe's chuck. When I made the cutters for the riveting head holder the multi tool that I used to…

Collet Conversion What kind of crazy thread is that? Well, it's the thread on Schaublin W10 collets. If you want to use a Schaublin collet in a Pultra 10mm lathe then you are going to need a draw bar with a suitable female thread. That was the challenge. Where to start? OK, I know what a buttress thread looks like; I've got one on my Record woodworking vice, photo 1. The Schaublin thread is a little smaller. Also, it differs from most other buttress threads I have known in a having a 5° angle on the leading edge ratherthan being perpendicular. Usefully, the male thread profile on the collet is sectioned by the keyway, photo 2, and it can be seen that the crest and root are both well rounded.…

Tailstock Lever Growing tired of constantly winding the tailstock quill in and out while drilling holes on the lathe, I recently raided the scrap box to make the lever attachment seen in photos 1,2 and 3. The accompanying figures 1 to 4 (and 5 to 7 to follow) show all the essentials to make the device. The blow-by-blow machining methods are closely detailed in a thread on the model-engineer.co.uk forum titled "Myford Lever Action Tailstock Design and Build”. https://www.model-engineer.co.uk/forums/postings.asp?th=177402 Thanks to input from forum members with access to the no-longer-made Myford lever tailstock attachments, I was able to produce a reasonable facsimile from some offcut pieces of 3/4” flat plate. The end result looks the part in my vintage machine shop and is a very useful accessory for drilling holes…

In lathe work there are many and varied ways of doing a job. Technology moves on but sometimes methods from the past still satisfy the requirements. One job that comes up occasionally is a need to work on a long workpiece that although it can fit through the spindle bore needs support at both ends of the headstock. This is for a couple of reasons. One to stop it flailing about for safety, which is a most important consideration. Even with support do not allow it to stick out very far and be mindful of the chuck speed. Secondly, to support it concentrically to ensure greater machining accuracy of the workpiece at the chuck end. A rear spindle steady or spider as they were called, fits the bill for such…

Much as I enjoy using machines to enable my many and various projects clocking objects on the mill does not add to the pleasure. One of the best purchases that I ever made was a rotary table. I saw a great idea for centring a rotary table under the mill spindle by Tom of Tom's Techniques on YouTube. Atapered pin was turned to match the taper in the centre of the rotary table and a half inch shank turned onto the piece in the same set up in the three-jaw chuck on the lathe in order to obtain concentricity, photo 1. The centring pin being loaded into a half inch collet in the spindle, the quill is lowered into the table until it stops at which point the table is…