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: Stone moving machine|
What are those smaller scars on it? Has someone been drilling holes in it?
|Thread: The last Gravity Ropeway|
That the one near Caton? (Sorry, Google has made Youtube such a faff, and so stuffed it with idiotic ad breaks through the videos themselves, I've given up on it). I've driven under it quite a few times when driving back from the Dales via Ingleton.
Is the brickworks closing too?
In t'other county, one of the two limestone quarries at Horton-in-Ribblesdale now has a private siding built a few years ago, off the Leeds-Settle-Carlisle line. The other hasn't for some reason (cost?) though it used to, so its crushed rock still goes out by lorry, over the village's two narrow hump-backed bridges separated only by a very sharp bend.
Dow n the road a few miles from there, the Hoffman Kiln (for lime) at Langcliife is worth a look if you're driving through the area.
One might imagine the public transport companies investing in all the tradee they are going to pick up as fewer and fewere people are able to own cars.
Well, we can imagine, but...
I live in a town whose local bus services provision is very uneven in coverage, with some outlying but large and growing areas having far fewer buses each day,and stopping ealier in the evenings, than others of similar size and distance from the town centre.
Oddly, the bus company, First, has been bringing in vehicles from Southampton (about 80 miles away) and Birmingham (some 170 miles away); still in their home liveries. It also runs our rail services, to London and to Bristol (the latter giving connections run by, among others, the German state, to much of the rest of the country). It doesn't paint "First" on the coach sides of course, but camouflage-names. Recently First has been cutting its services on both routes.
Its web-site's "Investors" page is illuminating. A couple of weeks ago, it proclaimed a price of £82 a share - eighty-two! It also carried a sentence, which when translated into real English seemed to suggest First plans to sell or close large chunks of its business for its so-called "investors".
I think a lot of areas of this country are going to be level in one respect... all equally isolated for any but their wealthy residents and the second-homers from Canary Wharf.
|Thread: Kennedy hacksaw-main bearing|
I think that burnishing to size by pressing a ball through is still used in some production work, but you may find that doing it to an Oilite will squidge its surface closed as you point out a reamer will.
|Thread: Mystery micrometer|
Possibly made for a particular range of products somewhere, by one of the tool-makers. Could even be an apprentice exercise.
I help wonder if it was originally accompanied by some form of bench-block or vice-blok that held it securely for use.
Measuring bore to edges as you suggest, including testing concentricity. Also possibly for setting between-centre boring-bars. Whatver its original purpose it looks very well-used but still capable of further service.
|Thread: What Did You Do Today 2021|
Own project - continuing fabricating my 4"-scale steam-wagon's ash-pan.
The club's steam loco - refitting its narrow bunkers after a service, presented the very fiddly task of inserting 4BA cheese-headed screws though their internal base angles. Casting round for something to hold the screws after struggling with pliers, such as stiff wire to make a crook, I spotted an oddment of bamboo from the garden.
Two cross-cuts with a hacksaw and there we were, and it worked: a screw-head collet made from Chinese grass!
|Thread: Stone moving machine|
It's as well when we try to guess how ancient societies built things, to remind ourselves that even erecting something as modern as the Iron Bridge over the Severn in Shropshire baffled industrial archaeologists for years because there are no written accounts of the technique. The only paperwork surviving is the accounts.
It was a chance sighting of a contemporary painting by a Swedish artist of the bridge at a very early stage, that gave the game away; proven by experiments with replica castings and accumulated knowledge of what was available at the time. And that was in the 18C, not some millennia pre-Roman.
Pgk Pgk -
The warm period is the one we inhabit now, starting around 11 000 years ago, but these are slow processes (in human terms) and the stones could have been dropped some thousands of years previously. If the hypothesis is right that they are erratics, and that is more credible than the idea of purely human action, it was an ice-sheet flow that transported them. Not glaciers. A glacier is very local and Southern England was not glaciated.
The henge's builders would have known the local Chalk was of little use but they could have used the relatively soft oolitic limestone from not too far away, the Greensand (a sandstone) if that outcrops from beneath the Chalk anywhere nearby, or perhaps the tough Carboniferous limestone from the Mendip Hills. Even maybe the Dolomitic Conglomerate (strictly, a breccia) that mantles Mendip, which looks good but it is horrible stuff to work so an unlikely choice. There is also a lot of sandstone around Bristol they could have used, but that is getting a long way for tree-trunk haulage.
I find it very unlikely they would have rollered huge boulders some 200 miles by modern road distance, including rafting them across the very dangerous Severn Estuary, up hill and down dale, from West Wales; when other rocks were available much closer to the site. The received wisdom that they did is simple, unquestioned correlation; but the ice-sheet hypothesis needed research and knowledge long post-dating the historians' idea.
Many old buildings in Exeter use very similar breccia for their bulk infill, and an easily-worked volcanic lava for the detail masonry; the structures date from as recently as late-Mediaeval; and both rocks are local.
|Thread: Upvc front door|
They do no need lubricating, Bricky, but much of the mechanism is inaccessible in most doors and windows.
|Thread: Bearing Location - Pulley or mounting block|
Also, if you over-hang the pulley as in the drawing, minimise the overhang by reducing that gap between jounal / axle-block and pulley face as far as possible.
|Thread: Metal Suppliers|
A very useful thread with several suggestions.
I've generally used the regular model-engineering retailers for most, but for larger and heavier sections such as for my workshop's overhead crane parts, used Pulham Steels, in the Dorset village of the name. Their main customers are trade including farmers, but they seel to the DIY customer as it were. I buy and collect complete lengths but cut to either needed lengths or to be simply transportable ("Oh, and the bar-ends too, please! ".
Scrap-yards can yield good finds but you cannot know the steel grades, and the production bar-end with a lovely faced end might prove an absolute what-is-it to machine on a small lathe with conventional tooling.
For sheet-steel work I have used old central-heating boiler panels, server case parts and the like. The thinner sheets are within the capacity of lightweight forming equipment, and its original use shows it of folding quality.
This is beginning to make me feel 'orribly like one of them so-called "influencers". Only they are paid for writing what are unashamedly advertisements. (I assume of course they pay their NI and Income Tax, and insure their bedrooms for business use!).
Toolstation stocks a limited range of architectural metals and a good range of the common ISO-Metric fasteners, circlips, all manner of pressed-steel brackets, tools etc. For non-model metalwork (equipping the workshop, making miniature-railway equipment, traction-engine driving-trolleys, etc.) it's surprising what can be obtained from TS and similar, primarily building-trade, stockists.
I've seen B&Q mentioned on this site. Its basic selection of light aluminium and steel sections is OK for odd tasks and I have bought from there, but the materials are primarily for small household DIY work not high-grade engineering, not cheap, and the quality of the steel can be variable. The canopy poles on my steam-wagon are thin-walled steel tube from B&Q, intended for e.g., wardrobe rails, but they are not supporting any significant load on the wagon. The company used to have a good on-line catalogue... Used to, but it's been re-written to conform with modern retail-chain practice.
|Thread: What Did You Do Today 2021|
You know what they say...
He who never made a mistake, never made owt!
New cars of any type have never been and never will be affordable for hundreds of thousands of motorists .
Second-hand battery cars will never be affordable by the same motorists if the car is being sold because the battery is reaching the end of its life.
Re-charging at home will never be possible for hundreds of thousands of motorists - including me - as we do not have private off-street parking!
Street-side charging is just not practicable or affordable except perhaps in a few estates of very expensive homes being built with the facilities from new. Even some modern estates now built, are 'Nouveau Pastiche' style terraces enforcing on-street parking that can be some distance from one's home. Their aim was to deter car ownership on a notion that no-one needs or should go anywhere other than work-places near-by. The idea of chargers on lamp-posts came from one or two politicians, most of whom show no technical knowledge at all. In any case the system would require vast quantities of high-power cables and chargers installing in thousands of miles of residential streets with enough room for all those charger parking bays as well as the normal parking, to be at all realistic.
The half-hour coffee-break while your own car is re-charging to at least a reasonable level is only part of it. As a hint on waiting times, VW claims for its latest electric model, a theoretical 180-mile range from a high-power charge for 30 minutes. There will never be enough public chargers, or the space for them, on busy motorways and commuting-routes, to avoid queues that cannot possibly be forecast; especially on cold, dark Winter nights. So a long trip will require considerably more planning, timing and precautions than we would presently think normal.
The public chargers and car connectors must also be of one consistent standard and the units must offer the option to pay by credit and debit cards as on many petrol-pumps now. Easy for us on this forum to say that though. We are engineers. Politicians are not!
|Thread: going carbide on a Myford|
No reason you can't use carbide tools on a Myford. What counts is the combination of tool and material, not the badge on the machine; and I find it necessary to choose tools on that basis.
Recently I turned a piece of right rough old steel, a portion of 18mm dia cable-drum tie-rod. Carbide tools would not work on it at all, fast or slow, without tearing. A freehand-ground but sharp HSS tool, reasonable speed and brushed-on cutrting-oil gave a fair finish despite the unpromising steel. Same lathe - an ML7.
|Thread: Lathe gear calculation|
I must admit I find it easier to use tooth- and turns- counts than decimal ratios, for most inch threads, because the sums are direct and clear, and don't invoke error bands, but as long as it works. Using decimals comes into its own for calculating for metric threads on an Imperial lathe, and that was the approach my spreadsheet uses.
More importantly though...
To clarify your last paragraph there though, there should be a reverser, probably within the headstock on Bevel's lathe and as on my Harrison, (external on the Myford 7) to nullify the reversal introduced by a 4-shaft set-up. I think his photos do show this.
An artificial tooth-count of 1 (not 0 obviously!) for an idler cancels that middle calculation and any potential rounding-error completely. I never calculate the idler but select any wheel that fits sensibly. My Myford's own chart shows an idler by just a hyphen.
|Thread: Cylinder drain cock thread?|
With great respect I think you may have mis-gauged the thread, for as you say 25tpi doesn't match any standard.
I think it is most likely 1/2 " X 26tpi BS Brass, whose tapping-drill size is very close to the core diameter you quote.
You could try the dodges others suggest, but I would make a test-gauge by threading a short piece of brass (or use a 1/2 " BSB fitting if available) and carefully try that. The reduction in diameter suggests it was not cut right through for some reason, perhaps to create a taper-thread effect.
If it actually is 25tpi, it is an oddity indeed.
You also ask the holes' purpose.
I don't know the engine but if it's a vertical the holes may be for tallow-cup lubricators. If so, I would expect smaller holes in the cylinders, close to the ends, for drain-cocks. If a horizontal then they very likely are for drain-cocks. Those are the outer end covers: what equivalents exist in the crank-end covers
I consider it wise, indeed normal practice, to fit drains "even" with slide-valves, but as I say I don't know this particular engine's design.
Whilst it is possible the water might lift the valve off its seat sufficiently to relieve the pressure, there is no guarantee it will do so, and the engine still has the problem of disposing of the water.
|Thread: Lathe gear calculation|
Just a gentle reminder gents...
Bevel's original query was an explanation of how the gear-train quoted is calculated to cut a 26TPI thread on a lathe with an 1/8" leadscrew.
Usually that is a simple arrangement but may need a compound train if the headstock pinion is large and the cut thread fine. This example looks very complicated in comparison, but we now know this is a function of the machine's design.
Starting from the top of the lathe, the leadscrew is driven from a pinion on the spindle (sometimes immediately following the tumber-reverse gear).
So that gear is a Driver.
It rotates another wheel, so that second is Driven.
That is common to any pair of gears: the one providing the motion drives the driven, but in the opposite direction.
Now, in a change-wheel set-up the spindle has to drive the leadscrew in the same direction. Therefore we interpose a third gear that does not rotate a shaft but passes the Driver's rotation to the Driven one; and in doing so it makes the Driven turn in the same direction as the Driver at the top.
That intermediate gear is called an Idler, or Stud, wheel, although the former term seems very hurtful because it is by no means "idle" ! It means simply that it is not rotating a shaft. Its teeth count does not matter as long as it fits between the other two wheels - in a simple train. It does matter in a compound train.
Now the calculations come down to matching the ratio between the thread to be cut and the thread of the leadscrew.
On an inch-dimensioned lathe with an 1/8" TPI leadscrew, if the thread you are cutting is an even number of turns per inch, the fractions are quite straightforward and you normally need use only one Driver (that up at the top on the spindle output) and one Driven (that on the leadscrew), linked by just one idler, on the stud somewhere in between them.
If we call the threads to be cut T and the leadscrew thread L, then L/T = Driver / Driven.
Make the two numbers small but even (as I did with 8/26 = 4/13) Then multiply both by 5: so 20/65 if the Driver pinion is of 20 teeth, making it a 65T wheel on the leadscrew.
I tried to understand that list you gave of 4 wheels but I'm afraid it flummoxed me and I wonder why it was so complicated. 70,65,30,60.
Sorry - if that is the correct order going down from the spindle, I could not make those figures fall out at all! I've tried various combinations of those but then I twigged 2 things:
- Have you quoted one extra: the 70T wheel?
- Does you lathe's driver pinion have 40 teeth?
For then, as you do not have a 130T wheel, you will need a compound train. It now falls into place:
The 40T pinion drives the 65T which is keyed with the 30T together on the stud. That 30T the drives the 60T on the lead-screw: Now use the (driver/driven) X (driver/driven) formula:
(40/65) X (30/60) = 0.3077. Which equals our original 8/26.
Eureka! If I have diagnosed the machine correctly, and that 70T wheel stays off the lathe.
Even-number threads with even-number leadscrews usually work out quite simply, and many need only a Driver-Idler-Driven trio. Fine threads do start to need compound trains and it looks as if this the case on your lathe.
So now: 8/26. Multiply by 5. (40/130) but to compensate for having no 130T wheel, we divide the work into 2 steps hence :
= (40/65) X (30/60)
A 46/65 duo with idler would cut a 13tpi thread, of course. That's not a standard inch thread but it is extremely close to 2mm pitch (45/65 inch = 1.954mm). Worth bearing in mind if you need cut a short M14 or M16 ISO coarse thread!
One point regarding setting the wheels: do not push them into tight mesh but allow a very slight play between them. The favoured dodge is to put a strip of ordinary thin printer-paper between them, lock them into mesh then gently rotate the machine by hand to eject the paper.
|Thread: dirty metric fudge|
I would not call it a fudge.
The important point is that you know its limits of accuracy (or precision - not a synonym but I can never remember which is which!).
|Thread: Uncertainty of Measurement [Global Warming]|
The whole matter has been so poisoned by ignorance, politics and commerce it's hard to know actually what is happening, but poor reporting standards and possible bias make things worse.
I wonder how many "Londoners" really would be affected by even a 1m rise in sea-level: how high are the Embankment and Canary Wharf walls above the maximum tides they see now, including storm surges which the Thames Barrier protects against? How many homes are genuinely in danger? Food shortages would be the bigger problem by affecting everyone in this country, even up on the lofty heights of Muswell Hill.
I understand there was a recent "report" from a supposedly scientific-journalism organisation that highlighted the above but was found to have used no more than a few estimates from American sites!
|Thread: Lathe gear calculation|
I can't help thinking there is a heck of lot of over-thinking going on here, of what has been and still is, a basic part of the art since the 19C!
The calculations for cutting a thread to the same units as the lathe (TPI on an inch lathe, mm pitch on a metric) are simple fractions; whether needing a single step or compound train, which is normally 2 but occasionally 3, fractions multiplied.
Cutting a thread of differing pitch-type (mm on inch and vice-versa) is a little trickier by usually needs a conversion 127 or 63T wheel, prime numbers; but not always. My Myford ML7's own chart gives several mm pitches with the "ordinary" wheels. Yet the arithmetic is the same.
Nor do you need know computer languages and programming for what is frequently a pencil, paper and calculator (or mental arithmetic) task.
The computer is valuable for creating tables made once and printable for workshop reference, but still only by ordinary "sums" in a spreadsheet. Mine, in MS 'Excel', gives metric and even BA threads, on an 8tpi-lead lathe with a simple 5-increment wheel range, to a fair degree of accuracy; by normal divisions and multiplications. It was a bit fiddly because I had to swap values around to narrow the errors, but a one-off that did not need compilers and languages, just the standard 'Excel' tools. It also shows the cumulative errors to assess maximum practical non-inch screw-cut lengths, usually longer than necessary anyway; and which may be impractical.
Engineering is performing physical, creative tasks in the best, simplest and most efficient ways, not adding work to make the most complicated ways!
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