Here is a list of all the postings Nigel Graham 2 has made in our forums. Click on a thread name to jump to the thread.
Thread: Harmonograph |
31/07/2023 23:14:40 |
If the harmonograph cited here is the one I think it is, with two pendulums (pendula?), its owner has exhibited it at 'The Fosse' a few times now. It is a lovely piece of work! |
Thread: Gear wheels |
31/07/2023 16:20:35 |
Are these change-wheels or internal ones? For the former, try a second-hand dealer like Home & Workshop Machinery. Alternatively, if you know the pressure-angle, a transmission-parts stockist like HPC, Bearing Boys, etc. . These firms sell stock gears that need their pilot bores and perhaps other details machining to suit the application; though now of course some might only stock metric-size wheels. Also most gears now are of 20º PA: they will mesh with 14º 30' wheels but not properly, in time harming both. |
Thread: Alibre There Eventually - Sort of |
31/07/2023 16:12:32 |
Have now managed to shorten the shaft to its right length (near enough) and to take that screen-shot - once I found where "paint" was hiding. |
31/07/2023 15:56:54 |
Nick - Sorry, I'm not clear what you mean about not design the dimensions. Surely you need know how big to make the parts before you can draw them? Besides, the central parts of this thing are two stock gears, so they dictated the rest. I'd gone wrong by not noting how big each bit is, first, then by not knowing how to dimension each part, then mis-calculating and mis-quoting the shaft length later. . Ady - What you suggest as exercises was more or less as I thought of doing. I was considering some of the parts on the drawings for a 'Stent' T&C Grinder, but other than the odd spacer or two, they all seemed a lot harder than the "string of beads" that I eventually tried. I did draw everything as individual part files, and had thought its assembly would be very simple as it is just a string of those simple cylinders with holes through them, around a plain bar. No gear teeth, driving-pins, keys, grub-screws etc. If I can't grasp doing that, I may as well give up. . One of Alibre's own tutorials - or was it that scribing-block? - does have you draw a thread, and yes it is a right awkward operation. As was the scribing-block's taper. All right if you need design the thread or want a very realistic image, but that's all. I've forgotten how, beyond the last move being the cut tool itself. Edited By Nigel Graham 2 on 31/07/2023 15:59:16 |
31/07/2023 09:31:23 |
Thankyou. It's actually simpler than the tutorials on the Atom Alibre web-site! Although based on investigating how to drive a small milling-machine needing a 20:1 speed reduction from motor to spindle; as a CAD exercise it should be basic. I omitted difficulties like the end-collars' grub-screws, and the operating-handle. I could have used parts from published drawings, to practice with, but they are no simpler. As an engineering exercise it proved interesting: I have used lathes with back-gears for many years but never really quite knew how they work! As a CAD assembly though, that drawing is merely four pairs of cylinders strung on one long cylinder. The eccentrics are the only complicated part. I did not deliberately remove the ring of pin holes in the larger gear. They vanished when I did something else to it. Drawing the accompanying drive-shaft with fast-and-loose gear and pulleys would be far, far harder; the complete gear-frame, beyond me. My practical approach would be to make the moving parts then work out how to build a frame to hold and connect them. It would be impossible to draw the entire system, motor and all. I would not even think about trying it, even with the milling-machine reduced to a symbolic rectangular frame holding the spindle with its pulley. (The machine, made for line-shaft drive, has the spindle inside an open, one-piece cast-iron frame whose top member holds the single over-arm.) . I realised where I'd gone wrong with the shaft length. I had miscalculated the length of the stack of parts initially when I drew the shaft. Later, I found that "Measure" tool to discover the real length; but then mis-quoted that in turn in re-drawing the shaft. I tried to find how to edit its length but found only how to change its diameter. . Ady - I was saving the drawing as I went along, so as not to lose everything. The only way to post a CAD drawing here is as a jpg file, so naturally not holding the information you mention. I know it's possible to copy an image of the screen, which may be what you mean, but I have never been clear how to do that. It's not obvious where you even find the command. |
30/07/2023 22:34:07 |
This gear-shaft assembly was the subject of my previous thread. It is effectively the back part of a back-gear type reduction drive using 4 gears I have , but represented here by their pitch cylinders. Originally the spigot on the smaller was to nest in a counterbore in the larger but that proved too hard to draw. Somehow 6 holes for screws to lock them together, drilled through the larger wheel, have vanished too. I miscalculated the length of the shaft. It should be the length of the rest. I could no find no way to shorten it except by re-drawing it; but that just seemed to keep running into trouble. Lesson One: make a dimensioned paper and pencil sketch first! Along the shaft there are: retaining collar, eccentric, an axial bearing washer, the two gears (their bearing bushes hidden), second axial washer, eccentric, collar. I have omitted finer details like the collar's grub-screws. Placing the eccentrics proved odd. I found it very hard to put in the grub-screw hole (just as plain hole); and that it worked was more luck than judgement. When placed on the shaft the first was aligned to the plane but its copy rotated itself by some random angle near 90º relatively to the first. That Component Placement tool would not act on it, and I had to pull it round into line by very tentative dragging until it looked right. If I actually make this thing I will mill seatings for the grub-screws so the eccentrics are in line. (I have no tooling for cutting internal key-ways with any certainty.)
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Thread: old french drill |
30/07/2023 21:34:46 |
Calculating the ratios is simple division, but those pulley calculators are valuable for giving the belt lengths for diameters and distances. I think I have one somewhere. I have for my sins four hefty great Mod 3 spur gears that can be assembled into a back-gear type configuration giving about a 4:1 reduction on their direct-drive mode, and I have been toying with designs for that. However it may a lot simpler to go for all-belt drive with a link-belt or chain for the final part, as the spindle pulley is surrounded by a lot of good honest cast-iron in one piece. The motor I have a single-phase 1HP machine of 1400rpm (actually 1350 but using 1400 makes for easier sums). So I need a total ratio of 20:1 for a cutter speed of 70rpm, a figure I gained from studying various text-books, with an option of, say, 140rpm for slitting-saws and drills. I'm tempted to use a single-way cone-pulley pair on the motor and first-motion shaft; or more safely just two pulleys so it will always drive downwards; then 65mm to a 250mm pulley I have in stock. So that's maybe 2: 1 then 65: 250 gives 182 rpm at the pulley above the machine. ++++ Talking of elderly French machine-tools..... Many years ago I rescued from a scrap-yard a very ancient, very unusual, French-built, Huré Universal Mill. We set it up in the workshop the club rented then, and drove it from a 3ph 3HP motor from an ancient shaper the mill had replaced. This was an odd machine. It had a double head, L-shaped in plan, that could be rotated on the column to bring into use either the vertical or horizontal spindle - followed by a lot of flat-belt changing to suit. The spindle ended in a threaded nose with a large, coarse-thread nut like a pipe union, but with a finer thread through the smaller bore, to hold the tooling in a taper of unknown type. None of us knew how that was meant to work as it had come with free swarf but no tooling. So I made a threaded insert to carry a small lathe chuck to hold the cutters. The thing was so hefty and had so many plain journals from motor to spindle that it took all the effort the poor motor could muster to bring it up speed! it was never really much use to us and eventually I passed it on to Weston Zoyland Pumping-Station Museum. I understand it later went travelling again to a new owner. So at least I had saved the poor old thing. I hope it's now in use somewhere! Huré later changed its name to Huron, and seemed to have been manufacturing machine-tools from the 1880s to the 1970s. Lathes.co shows my specimen to have been a type introduced in the 1890s. |
Thread: HSS/Tungsten Tool Honing Machine |
30/07/2023 20:59:51 |
That is fine tool-making! I like the centering method, with the two dowels: I'd not thought of that. I note your point about a little flat to prevent grooving the stone. Can the table also move sideways while rotating the tool-holder, for the same purpose? (The tip axis will still be at the same distance from the hone.) |
Thread: Denford pillar drill |
30/07/2023 20:47:06 |
I appreciate your point about the weight but might it be better to consider more how to move it around than how to take it apart? Especially as there is no need to separate the column and base for refurbishing it. Can someone help you manipulate it into its eventual position and set it up? Putting the table and head back on the column will be the hard bit, after all. |
Thread: Planimeter |
29/07/2023 23:21:44 |
I wonder if any of the various steam-engine preservation / rebuilding groups use Indicators and Planimeter . The formula is HP= n[PLAN / 33000] where P is Mean Effective Pressure in p.s.i. acting on the piston from lead to release , L = Stroke in feet, A = Piston Area in square inches, N = number of Strokes per minute (rpm X 2 for double-acting). The denominator turns the top line product, in foot-pounds/minute, to Horsepower. That 'n' is a fraction <1, or percentage, called the 'Diagram Factor', and is a rather empirical allowance for internal losses very hard or impossible to quantify. The letter was conventionally not an 'n' but a Greek character whose name I don't know, looking a bit like an 'n'. I think on a well-designed engine the Diagram Factor could be up around 0.8, even 0.9. . I can think of uses for planimeters in geographical work. Nature does not make areas of land, water bodies and the like to neat geometrical shapes. Nor, I very much doubt, really to those Fractals that were all suddenly so sexy to sum-smiths in the 1980s! |
Thread: Charity Shop Bargain |
29/07/2023 22:54:45 |
I have an essentially similar one, though without I try and find it I can't recall its make. I bought it quite recently, brand-new, too - within the last decade anyway, for use in my hobby of geology... but have never used it! .... I've also owned a "pair" of Suunto (Finnish-made) clinometer and compass, each reading to half a degree. They each fit a small aluminium-alloy block of identical external dimensions and bores, maybe 70 X 40 X 12mm outside. The clinometer uses a weighted protractor, the compass is magnetic; both are read by sighting past the index mark with one eye while reading the scale through a lens built into the body. Though of pocket-size they are on lanyards threaded through small leather pouches so they can be carried slung round the neck, for ready use. I do not know Suunto's history and original main market, but these instruments were once used extensively for surveying (mapping) caves to high grade, though more often now this is done by a type of laser range-finder and the data then fed into a plotting programme. I bought mine from a second-hand market near Glasgow, and when I cleaned them discovered they bore vibrator-engraver markings of University of Hull Geology Department. I haven't the foggiest idea how they ended up where they did; but they were labelled with rather vague ideas of "some sort of compass". I explained them to the staff, who obligingly wrote new labels for them. Ten minutes later I went back and bought them!. I no longer have them, but donated them to one of my caving-clubs. |
Thread: old french drill |
29/07/2023 22:27:46 |
Mon Dieu! Magnifique! Great to see it back in fine fettle and waiting for lots of holes to make. Arranging a drive would be interesting. I have a similar problem with a small Denbigh horizontal mill so might we find solutions similar? . I suspect that drilling-machine was never designed to whizz round like a modern machine, probably no more than about 200rpm at most, and was almost certainly intended for line-shaft drive, as my Denbigh is - and that wants only about 70rpm at the spindle. Do you have a matching pulley for that rather improbably overhung one? Flat belt material and clips are available from various sources, including I think Tony Griffiths (lathes.co). Alternatively, and what I am working out how to do for the milling-machine, carefully keep the original pulley as part of the machine, but fit a modern one to its shaft. That might some simple mm size for which a "Taper-loc" or similar bush is available, though it would be easy enough to make a sleeve for it. When I acquired the mill, its past (in more than one sense...) owner had built a confection of motor, old car gearbox and final-drive by chain, on an inelegant angle-iron frame above it. To carry the sprocket he had simply drilled and tapped a ring of small holes round one of the vertical faces of the spindle's original flat-belt pulley; and I may yet revise this arrangement. I seem to recall someone on this Forum once suggesting a flat pulley will carry an SP-letter vee-belt but I may be wrong and I don't know how well or reliably it would work. The problem I have with the mill and you don't see to with the drill, is that the driving-pulley is surrounded by the casting so needs either an inelegant drive from one side, or a link-belt or chain-drive from above. |
Thread: What is it and what is it for |
29/07/2023 21:44:51 |
Thankyou Nick. I based my comments on what seems the most my Warco 3-in-1 folder would be happy with, and what we've been shown here looks a similar capacity. I have also used a large Edwards folder and I think has a warning label of 16, maybe 14, swg maximum in mild steel; but I was also thinking of what the material being folded can take without cracking. |
Thread: Engraving - early attempts |
29/07/2023 15:49:02 |
First attempt? It is lovely work, the entire box and plate! I do like that "Latin"! Was that hand-work by gravers, a pantograph engraver or a CNC router? Just spotted: the two screws' slots are in line. I know little about guns but I isn't that a gunsmiths' tradition, a bit like clockmakers crossing out wheels to sharp internal corners? Edited By Nigel Graham 2 on 29/07/2023 15:51:34 |
Thread: What is it and what is it for |
29/07/2023 15:46:09 |
Dave - The kind of work I have in mind where a Keats angle-plates could be useful on a mill or drill is in, or on, the ends of cylindrical or square section objects, where it performs the roles of vice and Vee-block in one go. Recently I needed tap M6 holes in both ends of 18 aluminium bars, using a tapping-head in a bench-drill with low-gear setting. In the end I used a 3-jaw chuck on an adaptor-plate, but could just as easily have used the Keats block. I forget what settled the argument - I think it was the rod diameter a bit too small for the clamp. . Nick - There is of course a limit to what the bending tool will take, but also minimum radius to the bend to some extent depending on the material, and I would suggest 2mm thickness the absolute limit. |
Thread: Webmite Remote Watering System |
29/07/2023 11:13:26 |
I agree with Dave! Yes by all means build such a system as a project in its right, but for its own interest as much as function. I'd rather leave watering to the simple and very reliable little, self-contained, electronic timer screwed underneath the kitchen work-top, fed from a spare washing-machine cold-water point and discharging via micro-bore polythene tube put through a small hole drilled in the wall. Although quite easy to set, as I need touch it only twice a year I have to keep the instructions close by! All from a local garden-centre, not very expensive, surprisingly economical on batteries, and repaid itself over a good few years.
Remote-controlling your home to the nth degree is all very well till it goes wrong, but seems 'cos-I-can' rather than 'cos-I-need. It's not good engineering to make simple functions as complicated as possible, even if the control itself is still simple to use.! Keep the electronics projects for things like CNC machine-tools; and "wireless" to the broadcast radio and TV services . |
Thread: What is it and what is it for |
29/07/2023 10:57:16 |
First new "thingy" Metal-bender dies useable in a vice or with a fly-press. The magnets are to assist setting-up and help prevent them falling to the floor, which won't do their edges any good. . Second - Yes, it is a Keats Angle-block. Although its primary purpose is for holding work on a face-plate or Te-slotted saddle / cross-slide, it is quite a versatile "thingy" that can also hold for example, a work-piece vertically on a mill or drill table. A book on turning would be a better bet for information than the vagaries of You-tube. The "it seems" may just boil down to whatever single-project videos you saw, and their makers' available equipment - and opinions. I do have one, and bought it new only a few years ago. I don't use it very often but that's not the same as no-one using them "these days".
It use is fairly intuitive. The slots are for the bolts clamping it to the machine, the U-bolted Vee-block clamps the work between itself and the fixed block. For some purposes on the lathe it is better to wangle the U-bolt off its block and use instead two flat bars with bolts and nuts; or bolts tapped into one of the bars rather as on a tool-maker's clamp. This will reduce the amount of projections twirling round. (Mine takes a bit of wangling as the loosened U-bolt legs splay slightly!) . Noel - Shouldn't that be "Next slide please" ? |
Thread: Why do modern car engines have different types of bolt type heads like Torx etc? |
28/07/2023 22:32:53 |
My club bought from the local builders' stockists a set of flanged nuts for the studs holding the portable track sections to each other. A very good idea... Would be even better if the hexagons, though metric, are not the standard ones for any ISO-M threads (M10 or M12 but not 17 or 19mm a/f). I found similarly with other building fastenings I used for parts of my workshop installations. Over the years I have equipped my Myford ML7, which I had bought second-hand with few accessories, and found the new fittings needs an odd mixture of spanners! The basic machine is consistently BA and BS but the additions like the rear tool-post stud and its two Tee-slot nuts, and the steady's clamp-nut, seem to be Standard Somewherehandy. . Years ago I worked for an electronics company that serviced a lot of small Royal Navy equipment. The cases often bore warning labels about mixed thread standards. |
Thread: What is it and what is it for |
28/07/2023 22:04:24 |
Bring 'em on! |
Thread: X and Y references on milling table |
28/07/2023 20:28:31 |
That the slots do not align with your mill's long and cross-travels is probably more by chance than design, and while nice to have that symmetry it is not essential. One option, at cost of some headroom, is to fit the rotary table to a sub-plate made to give that alignment. |
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