Sommaire pour February 2024 de Model Engineer & Workshop

What do you want to see in Model Engineers’ Workshop? The curious way UK magazines are dated in advance means I'm writing this before we start 2024, I've been reviewing our content over 2023. A number of recent series and articles in MEW generated some interesting feedback from readers. The reprints of historic articles from the last 125 years we re well received, and though they won't feature in every issue, I'll look at ways of revisiting particularly good ideas from the past. Readers also like reviews, especially helpful are those of good tooling and machines. Some readers find very technical articles hard going, but these are always balanced by some readers who enjoy working through the calculations and exercising their grey matter. One recent series generated particular comment -…

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 While they contain much good advice, they also contain references to things that may be out of date or describe practices or materials that we would not use today either because much better ways are available offer safety reasons.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.…

TIP OF THE MONTH WINNER! This month's winner is former MEW editor Dave Fenner, who has devised a handy way to make cardboard more durable. Most of our workshop activities involve the use of metals, plastics and wood. As an alternative to wood, MDF may be used, and in the model railway world, extensive use of cardboard for scenic items is encountered. Some time ago I experimented with the use of MDF to produce a timing belt pulley. After cutting the teeth it was liberally coated with Ronseal Wood Hardener (RWH) which was allowed to soak in. While the device has seen occasional rather than intensive use, the pulley has nevertheless survived in good shape fora number of years. Moving on to OO gauge items, I had been fiddling about…

The aim of this article is to give some information about this gear tooth form modification (also named “profile shifting”) that can be very useful for avoiding undercut, getting a desired centre distance between shafts, increasing the tooth strength and more. This modification can be made easily with “generating” machines, the hobbing machines which are now quite common in model engineer's shops. It's nevertheless possible to make form cutters to do this. The free software “Filengrene” described in an earlier article (MEW 331, 332) can be used to solve all the gear definition problems with no calculation, and do even more for those with 3D printers. How and why of the involute profile From friction wheels to gears (Sketchl and video ref. 1) If power is transmitted by friction between…

This short series of articles describes a ‘new’ design of boring and facing head, photo 1, developed in the light of lessons learned and feedback on my previous design. The previous boring and facing head that I designed, HSM July/August & September/October 2016, EiM AprilMay 2012 and page 7 “Projects for your Workshop Vol 1”, leaned heavily on the second generation Emco boring head design. A drawing of the Emco unit is attached at photo 2, (reproduced courtesy of the EMCO Group, Austria). The facing facility was added to this design as I was familiar with the Emco head. This seemed a natural route to me to use a proven design. Thereby retaining continuity of operation and the use of existing tooling. This design has been received with some mixed…

I then used a piece of 5/16” tool bit to set one chuck jaw back by that distance, and slid the job along to again touch that jaw before nipping the other three jaws up again. So far still so good. Now to bore the “half a hole” centred 5/16” from the existing one. But alas! How to drill the starting hole for the boring bar in the centre? It can't be done. I tried starting with a smaller boring bar to bore a small overlapping “half a hole” for starters. But it flexed too much under the interrupted cut. So I went back to the large half-inch shank bar and nibbled my way through the job by feeding it in 10 or 20 thou at a time until the…

Many readers will be aware that I am something of an evangelist for 3D printing. Recently I've been trying out the Creality K1-Max AI (I'll call it the K1-Max for short), one of the largest and fastest hobby-level 3D printers, photo 1. This machine has so many interesting features I'd like to put it in the context of my prior experiences in 3D printing. I got into the technology around the point where reliable and capable fused-filament- deposition (FFD or FDM) printers were becoming relatively affordable. Just to recap, this is the process where a computer-controlled machine extrudes semi-molten plastic in layers to build up 3D objects. Objects can be downloaded from the internet, you can design your own with 3D CAD, or even scan in objects (see MEW 335).…

Save a stamp! You can now place your classified ads by email. Don't waste time scanning the form, just send the text of your ad, maximum 35 words, meweditor@mortons.co.uk, together with your full name and address, a telephone number, whether it's a for sale or wanted and stating that you accept the terms and conditions for placing classified ads - see below. Please note, we do not publish full addresses or website links to protect your and other readers’ security. www.model-engineer.co.uk/classifieds/ Tools and Machinery ■ Southbend lathe 4 ½ × 18” 3 & 4 jaw faceplates gears, stand, £300. T. 07788 442032. Macclesfield. ■ Myford ML7 240V, motor reground bed and saddle, new tailstock barrel, half nuts, Oilite bushes, engraved dials, 3&4 jaw chucks, 3 way tool posts jacobs chucks…

Rotary tables and dividing heads are tools used to rotate workpieces accurately through various angles. Typical applications are cuts at fixed intervals to make gears or dials, photo 1, but other applications include machining curved surfaces and fabricating complex shapes, photo 2. Typically rotary tables are heavily built with a large flat faceplate to which a workpiece can be attached directly, or alternatively chuck can be attached. They can be used with the axis vertical, photo 3, or horizontal, photo 4. Dividing heads are typically lighter and may use collets or chucks to hold the work. Rotary tables nearly always use a worm gear to provide the primary means of accurate rotation, photo 5, while dividing heads are more likely to use direct indexing from gears or index plates, though…

A recent article in MEW 423 (“Safely turning long objects in the lathe” by Brett Meacle) reminded me that I had intended to make something that would handle long workpieces extending out of the back of the headstock. Photograph 1 shows an example of the problem. I had already come up with several ideas ranging from a rather fanciful contraption based on the iris in a camera lens (that never made it to the sketch stage) to something very similar to Brett's device. My difficulty is that the end of the headstock tube on my Harrison M250 is almost flush with the casing, as can be seen in photo 1. I could remove the casing and override the safety switch, but this is hardly ideal. Instead, I needed something that…

The Roll Ranger When I was offered the chance to review this, I nearly didn't bother, after all it's not an engineering tool. But on reflection, how many times have I spent ages trying to find the end of different rolls of tape in the workshop and elsewhere. Invented by physicist John Ellis, expectations were high: “Certain inventions solve a problem so easily that you wonder how you ever got through life without it, and the Roll Ranger is one of those inventions! Have you ever struggled searching forthe edge of the tape or end up tearing it then opting for a new roll? Roll Ranger has come to rescue, and is the ultimate solution to all yourtape troubles.” I have to be honest, this little gadget works wonderfully, reliably…

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. GHT's Universal Pillar Tool Dear Neil, I was very interested in the article on the pillartool in MEW 334. For many years I have tapped holes using circular sleeves to hold the taps at right angles but having invested in a mill two years ago, which had improved my ability to work accurately by at least an order of magnitude, I felt that something to hold the taps with a greater level of precision was needed. There are other tapping jig designs, for example Harold Hall's in…