Here is a list of all the postings Kiwi Bloke has made in our forums. Click on a thread name to jump to the thread.
|Thread: The Chocolate Fireguard as designed by Mercedes Benz|
...and another thing... See, now you've got me started...
We have a new Honda Jazz. It's great, and one of the cheapest new cars in NZ. The control electrickery seems to marry the CVT and its torque converter together pretty well. I was fearful that they would'fight' each other. Gentle journeys can be done at 4.7 l/100km. It has an electronic fuel gauge.
We were about 30km from home, with a soon-to-expire, generous 40c-off per litre fuel voucher to use in our home town, but not where we were. The fuel gauge showed near-empty, with the warning annunciator lit, and the display showed the calculated range to be 20km. OK, into the nearby pumps for a $10 splash. Program the pump for $10 delivery, pull the trigger, and enter daydream mode. Back in the car, driving away, and the fuel gauge shows empty, etc., and still only 20km range. Back to the pumps. Not sure whether the pump automagically delivered $10-worth of fuel, or just fired blanks. Attendant assured me all was OK. Put in another $10's-worth, just to be sure (listened for the filling noises this time). Drove off. Gauge and range calculation unchanged.
The tank should now be about 1/4 full, but the electronics didn't know. Slowly, ever so slowly, we started generating petrol, as the gauge climbed up - to a stable reading about 20 km from the pumps. The range calculation resolutely stayed at 20 km. The journey was about 30 km. The thing had no shame.
Probably a good job it wasn't a life-or-death situation...
Progress. A couple of days ago, Mozilla 'forgot' to renew a certificate, so all (security) add-ons for the Firefox browser were disabled. Gmail has recently thrown a wobbly. Pilots fight and lose against airliners' safety-enhancing systems. Auto-piloting cars crash, for no apparent reason. Algorithms of Byzantine complexity make decisions too quickly for errors to be identified, and no-one understands what the hell is going on. The stock market has a 'blip'. Machine 'intelligence' learns by implementing heuristics it has 'learned' by processes no-one understands or can identify. Therefore no-one can tell whether the AI is correct or not, except by results - when it's inconveniently late for an error to be detected. And some of the mistakes are extraordinary. The prof. of security engineering (how's that for a concept?) at Cambridge won't touch internet banking.
It was nerve-wracking enough sitting in the passenger seat when junior was learning to drive. Luckily, instructions to go slowly were heeded. But how would it feel to be a passenger in an auto-piloting vehicle, with super-human reflexes, seeing all around itself, and making decisions far more quickly than the hapless, half-asleep and de-skilled human 'supervisor' possibly could, and speeding along, perhaps at speeds beyond the ability of any human driver, particularly in a complex environment. And yet the human is presumably expected to be able to take control as soon as (s)he senses that the AI has stuffed up. How relaxing to be a passenger!
And then there's the worrying problem of the AI's 'moral code'. Who gets sacrificed in certain accident situations (eg the owner, in a head-on smash, or the queue of people waiting at the bus stop, if the car swerves to avoid the head-on)? Will you be able to pay more to have a 'protect the owner at all costs' rule programmed in?
Since most garages seem incapable of sorting out existing misbehaving control systems, we can look forward to chaos when our electric vehicles have a slightly intermittent contact somewhere, or a bug that rarely manifests itself...
Progress? It's too easy to build complexity into software. Features are added 'because we can', and it doesn't cost much. But 'because we can' is not a good justification for doing something.
Rant over - for the moment.
|Thread: Bore micrometer|
You asked: 'Would it be less fiddly (better) or more fiddly to use a high quality telescopic bore gauge (eg Mitutoyo) with the aim of measuring down to 0.001"?'
Well, have you ever tried? Telescopic gauges need a bit of practice and a fine feel to get consistent readings, and, of course, are just transfer devices - the micrometer does the reading, so multiple error mechanisms. Certainly more fiddly. A decent bore comparator should indicate 0.0001" and can be set, as suggested, against a micrometer, slip gauges, etc. It will also directly indicate out-of-roundness and taper. Also need a bit of practice and finesse, but easier than a telescopic gauge (at least in my hands).
If you want a bore micrometer (of the three-leg variety) get a mortgage. If the bore is large enough, however, an internal micrometer is fine, and about as fiddly as a telescopic gauge, but at least reads directly.
|Thread: Oil, lubricating the lathe|
The reason why slideway oil (ISO 68 grade, eg Febis 68) is specified is because it's designed to minimize the 'stick-slip' phenomenon that will most likely occur with other oils, making accurate, fine adjustment of feeds a problem, particularly when gibs are adjusted to very little clearance (ie correctly). It is also 'sticky', so is good on the leadscrew, where it won't drip off so readily.
'Hydraulic' oils (eg Nuto 32) have good lubricating and anti-corrosion properties and are fine for plain headstock bearings. I believe that the detergents added to motor oils, to keep muck in suspension, allow water to be absorbed into the oil, which is not exactly a good anti-corrosion measure.
A bit of MS2 grease or 'assembly paste' works well on feedscrews, although beware of the ability of grease to carry swarf, etc. where it's not wanted.
|Thread: Loctite minefield|
There's a wealth of really good information only a couple of clicks away, at the manufacturer's website...
Loctite change the numbers of their products from time to time, so what follows reflects my stock, not what the latest numbers may be. Hopefully, they haven't changed.
222, 'Super Screw Lock', is suitable where the fasterer that has to be undone has a long thread engagement. The amount of torque needed to break the bond will be related to the area of thread that is bonded, so avoid high-strength products for screws (in most applications).
243 is a medium strength preparation, stronger than 222, and is suitable for nuts, or where there is short thread engagement if screws are used.
These two will probably take care of almost all needs.
609 is a high-strength retaining compound, and if used on fixings, will be awkward to undo, without heat.
If you think the plethora of Loctite's retaining compounds is a nightmare, don't even think about their range of sealants, etc.!
Hope this helps.
It's pronounced 'Ooooooooh'!
|Thread: 6" EME rotary table|
Nice rotary table! I don't think you'll be disappointed at all.
Elliott were a bit more than badge engineers. See **LINK**
Clearly a complex business arrangement. From what I've handled, seen and read, their equipment was no-nonsense, reliable and good quality, although not in the same league as some of the premium European, or better British manufacturers. Their products were a mixture of British-manufactured (by the companies they owned) and some imported gear, e.g. the Unimat, which they imported for a time.
I'm very happy with my Progress 2GS pillar drill (made in Peterborough). Spares were available in the late '90s or early 2000s from Gate, who appear to have picked up some of the pieces when the inevitable British Disease caused Elliott's demise.
|Thread: "Screwing" a car round a corner!|
Understeer, oversteer, total loss of control - all these things were possible in a Hillman Imp on crossplies. Luckily, it was usually fairly safe, because break-away occurred at such low speeds.
Fast-forward a bit. Lotus Seven Big Valve Twin-cam, with LSD. Not sure what the steering wheel was for - you steered it with the throttle.
And somewhat later, a Subaru Impreza turbo. I tried to unstick it on most trips out (it became a challenge, you see...), but, by the time it was sliding, it was going so damned fast that it was dangerous. But perhaps I had grown up.
|Thread: A visit to Manchester Sci and Eng Museum|
I went into the museum once, in the '80s. There was a cut-away Rolls-Royce Merlin. I stood before it in awe. So huge and complex, obviously with an enormous amount of hand finishing and fitting. How many man- (and woman-) hours went into making such magnificent things? Of course, I had seen cut-away drawings before, and had made the plastic kits of aeroplanes with these engines, but seeing the thing in the flesh, indeed inside the thing, was altogether different. Imagine the price, if one were manufactured today! And all for an average in-service life of ten hours, before the fighter pilot behind it was shot out of the sky. And they were made in their thousands. The war effort. So much effort; so much was given - by so many. The tears rolled down my face. I had to leave. I never went back.
|Thread: Moving to Australia - Moving Workshop Machines|
Good luck with your move. Don't sell anything - in fact fill all possible container space with gear bought at UK prices because it'll be more expensive at your destination, or will be oriental stuff of questionable quality. Research the market and make a bob or two. I wish I had...
We moved from UK to NZ in 2005. The workshop equipment filled a 20ft container. Everything possible was crated, the bases being 1in ply on spacers of sufficient height to allow a pallet truck underneath. OSB board walls. Machinery was bolted in and smaller items packed tightly into compartments. All bare metal was sprayed with anti-rust stuff. It was a lot of work. Ensure nothing can move or rub against anything else. Weeks of gentle movement at sea, and brutal treatment at the docks can do amazing things - there is no shortage of horror stories.
Everything was fully insured. Beware that some policies are void if the shipper does not unpack the lot. However, I was more worried by the ship going down, or the container being lost. Since the move, I have seen photos of stacks of containers falling off ships, being dropped by cranes, etc. Had I seen these before the move, I think I may have chickened out... Luckily, everything survived.
I was warned to beware the idiot bureaucrats whose sole purpose is to get in the way of common sense. Bio-security is taken seriously in NZ. The presence of a foreign fruit fly in Auckland recently made front-page news and caused panic, just like it did last time. I tried to research what hoops I was expected to jump through. Apparently, any timber used for packing, crating, etc. had to be 'treated' and 'certified'. What treatment and certification? By whom? No information. Then I found a document stating 'if treated timber is used...' (my emphasis). So did timber have to be treated? No-one could tell me. Containers were often fumigated with methyl bromide (IIRC), which sounded like it would do precision machinery a power of no good. I eventually found the 'phone number of an NZ inspector and asked for guidance. He said, in effect, that if nothing crawled out of the container when it was opened, it would be OK. Probably. Ah, the famous Kiwi 'She'll be right' approach in action. As I said, bio-security is taken seriously here.
When the other container of household posessions had to be cleared through customs, etc, I had to fill out a questionnaire including questions about whether anything was of plant or animal origin (complete with DIRE WARNINGS that it was prohibited!). "Er, what about wooden furniture, books and papers, cotton and woollen fabrics, leather shoes, etc." Look of puzzlement from bureaucrat. "Oh no, those don't count." That was one of many WTF moments. I lost 1 1/2 stone in the month of the move. Make sure you have an ample supply of stress pills.
|Thread: Page errors in 4610|
Hey, you guys are lucky! All the pages of my copy of 4610 are missing. Same with 4609. That's one of the joys of living on the far side of the world - subscription copies take an age to arrive...
And, of course, the delay is made worse by time getting here earlier...
|Thread: Windows Update (Again)|
Well folks, if you want to pay through the nose to be an enslaved drone in the Microsoft or Apple hive, go ahead, but if you want to be in control of your computer, enjoy reliability and better security, go for Linux or BSD and spend the money you'll save on beer.
|Thread: myford super 7 problem|
A bent leadscrew can do this (assuming the cut was with self-feed acting). Mount a sensitive clock on the saddle, bearing on a vertical or horizontal guiding face of the bed, turn the leadscrew, and watch for indication of horizontal or vertical movement of the saddle, in step with the leadscrew turning. Not an unknown Myford phenomenon.
|Thread: Meek screwcutting dog-clutch|
Graham; I've pm'd you.
|Thread: Quality issues with a SIEG SX2.7 mini mill|
Twelve hundred quid for a brand-new precision machine, and from China? Sounds too good to be true.
From what we see and read on many fora, manufacturing and inspection is so hit-and-miss that there are bound to be a few good 'uns escaping, but yer pays yer money and yer takes yer chance. A friend has a small Chinese CNC mill clone and thinks that it can work to micron accuracy. I haven't the heart to offer to do accuracy checks of the machine for him, let alone investigate cutter and work deflection under cutting loads, etc. Interestingly, the maker's spec. quotes 0.01 mm accuracy and 0.015mm repeatability. Not exactly jig-borer spec., is it? Neither is the price.
|Thread: ML10 Hammered Paint|
Well, it seems that I've come to the party, fashionably late... FWIW, here's an answer, of sorts, to the original post.
For the green Sevens, Myford used Trimite 2-pack polyurethane. Nasty stuff, because of isocyanates, and I don't think Joe Public could get the stuff easily (safety gnomes at work). When I toured the factory in the '90s, I possibly also saw 10s being painted, but I can't remember noticing the paint used.
I had some things professionally painted hammered silver-grey, and IIRC, that was Trimite too. I've a nasty feeling that Trimite is no more. Perhaps a name change?
I always found Hammerite to be a disappointment. Ghastly to apply by brush, poisonous to spray, and spraying never seemed to result in anything resembling a proper hammered finish. Also, it was brittle and not at all durable. I can't believe Myford would have used it.
Rustoleum do/did rattle-cans of hammered finish paint. A thread elsewhere said that a green ('olive green'?) was a reasonable match for Emco's original Unimat green. Sadly, as far as NZ is concerned, that colour seems to be locally known as Unobtainium. Bother!
|Thread: releasing tapers|
Probably best not to add complication to the tang discussion by mentioning 'use-em-up' sleeves.
Wish I hadn't.
OK Hopper, I'll bite...
'...a different kettle of fish...' Very good! Clearly a sly pun, alluding to the Poisson ratio, which is of central relevance to what I was rambling on about!
Clearly, following a whack on the little end, the outwards deformation of the inserted male member (can I say that on this forum?) in the female socket will be miniscule, but would be detectable with a strain gauge on, say, the outside of a tailstock barrel. A compression wave will indeed travel through the tool (and socket): (elastic) deformation will not be confined to the tang. And, of course, whacking the thing (usually) gets it out, so any transient increase in the friction holding the things together will be overcome. However, given Poisson's insight into deformation mechanisms, pulling things out of tapers should be easier than pushing - although perhaps less practicable. That was my message - for what it's worth.
Anyone who has used a Clarkson 2MT collet milling chuck, with its 'steadying ring', will know how readily tightening the ring can release the taper. Ideal geometry for release.
I'm not trying to labour a point here, nor wishing to disagree with anyone - just indulging in a bit of theoretical whimsy - but I always cringe when anti-friction-bearing-supported bits of machine get attacked by hammers. Unfortunately, often there's no sensible alternative.
Clive Foster's Atco experience is fascinating - I must try to remember it for future use.
I've been thinking about releasing things stuck in tapers. I hate whacking the things free - it must do the bearings a power of no good. Self-ejecting arrangements, captive draw-bars, folding wedges and threaded collars at the nose end are so much gentler.
The trouble with thinking is that the more I think, the confuseder I get. When a bullet is fired, the back of the bullet starts moving before its nose. A compression wave spreads out through the bullet at the speed of sound (ie the speed of sound in whatever the bullet's made from). This causes the bullet to be plastically deformed - if it can 'go' anywhere - increasing in diameter, and contributes to the bullet being forced into the rifling grooves, and stops gas leakage. (Impressive and somewhat hair-raising experiments were done in the early 1900s by F W Mann, which involved the recovery of fired bullets without their suffering significant damage after they left the gun.)
Something similar (although elastic) presumably happens when the tang or small end of a tool in a taper socket is whacked. I would suggest that the whack will cause a transient increase in the radial forces between the tool and taper. Perhaps, if the whack is smart enough (not from a dead-blow hammer), the compression wave is followed by a 'tension' wave, which helps release. It would be better, (wouldn't it...?), if the blow could be applied at the large diameter end, so that there was only a wave of tension. Perhaps a slide-hammer puller, applied to the outboard end of the tool, or whacking a rod lying in a deep axial hole, bored from the small end, the end of the hole being beyond the wide end of the socket.
If this sounds crazy, just think about how you'd get a long rubber plug deep into a tube with an ID smaller than the plug's OD. You'd easily pull it in, but pushing would be impossible. I believe this is how the trailer 'Indespension' units were assembled (are they still going?).
This isn't meant to be a serious practical suggestion, just thought-provoking. Perhaps I should have gone to bed before now...
|Thread: Myford tailstock ML7 / Super 7|
Just remember to check the centre height of a replacement tailstock. I don't think Myford held to specified dimensions too rigorously - it was easier to fit individual parts to each other.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.