Member postings for Kiwi Bloke

Can Clive Foster please expand on setting the dashpot correctly? As far as I can discover, the manufacturer's 'special' oil is an ISO VG460 oil, which might as well be Unobtanium in small quantities. Perhaps that's why 90% aren't set up correctly.

Can Clive or anyone else suggest a suitable dashpot oil? And, for bonus points, one that can be had in New Zealand?

I'll try to reply to Alan's question...

The pic doesn't show the working end of the gauge, so it can only be an assumption that this is a standard 4-point-of-contact bore comparator, in which the two non-moving points are set on a chord of the cylinder, and the other two points oppose each other, lying in a line that perpendicularly bisects said chord and thus define the diameter of the cylinder. It is this diameter that is gauged.

3-point-of-contact bore micrometers have all three anvils moving, 120 deg apart (resembling a Mercedes Benz motif). And yes, they are horribly expensive, even used.

Getting the angle of a push rod absolutely correct is made a bit tricky by the taper of the gib. However, many well-respected machines get around this problem by interposing a ball bearing between a flat-ended push rod and the gib strip. Of course, point contact is not ideal, but, in practice, taper gibs are stout enough not to be distorted (and there's nowhere for them to bend), in spite of Clive Foster's warning. At worst, a small dimple will be produced on the 'back' face of the strip, and it will take a lot of gib strip longitudinal adjustment before any raised lip of the dimple bears on the slide's gib-strip-bearing surface.

Oh, thank goodness! Martin Connelly and Hopper are spreading the light!

The tradition of sneaking up to size by a succession of drill diameters, increasing by small increments, has had its day and needs to be laid to rest. It may have been appropriate in the days of treadle-driven lathes, but is wrong-headed for the reasons stated. If your machine really can't take the cutting loads, you'll have to use multiple steps, but each one comes with the risks stated, so try to use as few increments as possible. And start with a 120 degree spotting drill, never a centre drill!

Great! Perseverance pays off!

If the connection was poor from the outset, it would have tended to run hot and oxidize - a vicious cycle until failure. Not an uncommon scenario - thinking in general, not just motors. To re-phrase what I said before, all connections are suspect until proven otherwise.

I wouldn't worry about temperature. Old stator windings would have been bound with linen tape. Modern, warm-running, totally-enclosed, fan-cooled motors can run with a case temperature around 60C. I think that exposing the insulating varnish to various solvents, resins and other chemicals is living dangerously. Epoxy should be safe enough, however. Beware silicone resins also - most evolve acetic acid during the curing process. So-called 'Neutral Cure' types are available, however.

I think I keep my old computers for many of the same reasons that I keep my old wife. I've got to understand their ways (to a limited extent), they still work, my requirements are much as before, and newer models tend to be expensive...

If the Haltrac is defunct, someone might do the community a service by 'reverse engineering' one and publishing the design. The lock is the clever bit. Along with all sorts of other things, I lifted a Lotus Twin Cam engine, with 200E gearbox attached, several times with mine. Must have been >3cwt. Somewhat hair-raising, given the thinness of the rope. I wonder where I put it...

Beware of putting severe tension loads on T-slots. John Baron's toolpost obviously hasn't caused the T-slot to break (yet...), and he has fitted a reasonably long nut. I think I'd use the longest nut I could fit and would ideally spread the load by fixing the post to the nut in more than one location. The Myford/Thomas style above takes the T-slot protection further by spreading the load between two slots. The quick-change holder then adds flexibility and moves the forces outside the footprint of the post. Nothing is ideal, is it?

More encouragement not to give up!

I'm not clear whether you've isolated the start winding and tested it for continuity. It would be really bad luck if the start winding has burned out or was broken in manufacture. I'd still suspect a wiring or connection problem. Never trust soldered, welded or crimped joints, however good they look! You've nothing to lose - dive in deeper! Good luck!

Alan, I've PM'd you.

Have you seen the documentary video 'The Lightbulb Conspiracy'? It's on YouTube. Take Valium and a blood-pressure pill before, though... Essential viewing for the likes of us, who enjoy the reliability and life-span of honestly-engineered machines.

The video contains the revelation that Epson inkjet printers apparently contained (may still, for all I know) a page-counting (or ink-usage tallying) chip, which permanently shut the beastly device down at a certain number. Not user-resettable. The given reason was to avoid the pad which captures the ink from head-cleaning cycles from saturating and overflowing. Yeah, right!

I have a 16-year-old Epson photo-quality printer, which has printed a handful of beautiful A4 photos. The rest of the time, it just wasted ink and paper at a ferocious rate, trying unsuccessfully to unclog the heads. Infrequent usage, of course. Also had problems with Linux compatibility, which also affects an Epson scanner. Well satisfied with my Brother double-sided printing mono laser, operating fine on Linux.

Any company that cynically engineers sabotage devices into their products should be dealt with most severely.

Edited By Kiwi Bloke on 31/01/2020 00:04:59

OK, 'bye. What on earth's upset him now????

If you're lucky, the guide bush - end mill (or even drill bit) approach above will work just fine. However, it hasn't always worked for me, especially for slender cutters, because the off-centre forces on the milling cutter may cause it to cut sideways into the bush. After a ridiculous amount of procrastination and analysis-paralysis on one job, the solution came. Add a sleeve to the cutter (superglue), so the guide bush is protected: only the sleeve runs in the bush, the cutter becomes an end-cutter (only) and the whole setup gains rigidity as a bonus. Good luck.

Interesting thread...

In retrospect, I realise that I have found de-soldering modern equipment to be more of a challenge than it used to be - even allowing for component density, failing eyes, etc. The comments above to first add solder was a lightbulb moment, I think. I customarily use a well-loaded iron to de-solder. I thought it made things easier because it provided better thermal contact, but I bet it's a lot to do with adding lead to the new-fangled lead-free solder joint. I don't use lead-free solder, know that it doesn't flow as well as 60-40 and a repair man I know says the move to lead-free was the stupidest thing ever forced upon manufacturers. The joints are prone to failure, tin whiskers grow between tracks and components and (elderly) joints just seem to fall apart. After a dose of lead into the joint, solder suckers work pretty well.

So, the message is: add solder first, but use good old 60-40 lead-containing solder!

When people disagree with me it's invariably because they haven't thought it through adequately...

The Canadian psychologist Jordan Peterson has become somewhat infamous, and has attracted much hate, by daring to challenge political correctness and many widely-held 'truths', which are in fact no more than dogmas. You can find many videos of his talks and interviews on YouTube. He frequently prefaces answers in interviews with 'Well, it's complicated'. How true! Life is complicated, science is complicated, logic is complicated and there is so much that can be shown to be true, whilst being disconcertingly counter-intuitive.

The sad fact is that most people have not been educated to think critically, or even to think for themselves. With the explosion of 'the media', it's too easy for the ignorant or devious to broadcast garbage. It's also too easy to soak up, passively and uncritically, pre-packaged ideas and opinions, rather than to think or learn. Hopefully, knowledge and wisdom, and an appreciation of how complicated things are, comes with age, which is why, I suggest, the older I get, the more exasperated I become with idiot politicians (etc.), whose simplistic evaluations result in knee-jerk 'solutions', and inflexible following of political dogma. I don't think I'm alone. Grrr!

I'd better stop now, calm down, and take my pills...

OK, perhaps it's more correct to say that X-class caps are allowed to fail short, whereas Y-class must not and are designed accordingly. The message is that one should choose the correct class of cap if replacing caps connected to the mains, i.e. X-class between Live and Neutral and Y-class between Earth and either Live or Neutral. Be careful!

'Its satisfying to keep these old machines going using skills knowledge experience and of course the internet.'

Absolutely! Save the planet! Join the Right to Repair movement!

Just to tie up a few loose ends about these things, for anyone who's interested...

These three-leg capacitor networks comprise one X-class capacitor connected L-N and two, equal-value, Y-class capacitors, one L-E, t'other N-E, hence the 'delta' moniker. X-class caps are designed to fail by going short-circuit. This should blow the supply fuse or breaker, alerting one to the fault and rendering the device 'safe' - i.e. unpowered. Y-class caps should fail open-circuit. If failure were by short-circuit, the frame of the device would be connected to the mains live or neutral - not desirable.

I've looked in a couple of catalogues and am surprised to see many such devices are of metallized paper construction. Given my experience with this construction failing, I'm surprised. However, dredging through the memory banks, I think the failures were all of the same make, so perhaps metallised paper per se is OK, but 'my' caps' manufacturer was the culprit. I note that above I've said '...designed to fail...': I wonder...

I'm pretty sure that the 'yellow thing' is a mains suppressor, comprising three capacitors in a delta network, and it's certainly the culprit. The second line of print on it (obscured at the start) is probably decoded as '1 off 150nF and 2 off 2.5nF'. It's followed by a 'Y', which presumably identifies the capacitors as Y-Class. 3-capacitor delta suppression networks are used all over the place, made by many manufacturers, and available from places such as RS Components. Cheap. Component values won't be critical. No need to hunt for a 'Makita' one, just get one around the correct values (there won't be much choice) and a suitable physical size. And search the 'net for delta suppressor capacitors or similar, for more info.

One leg to live, one to neutral and the third to ground (earth). The spring will just be the ground lead's connection to the motor's earthed frame.

Incidentally, these days, X- and Y-Class suppression caps are usually metallized polypropylene, and fail in a dignified manner (if at all). I have replaced several older metallized paper suppression caps which failed with smoke, flames, bangs and a disgusting smell. Before the fireworks, they often swell, so there's sometimes some warning. For some reason, they are still available. Description in a 2013 RS catalogue contains 'high safety regarding active and passive flammability due to metallised paper construction'. Diametrically opposite to my experience! They seem to last about 20 years - well out of warranty, so who (except me and thee) cares?

Edited By Kiwi Bloke on 26/01/2020 10:12:40

The engineering graduate asks "How does that work?"

The physics graduate asks "Why does that work?"

The arts graduate asks "You want fries with that?"

As Hopper suggests, a 'bit of shim will do the job'. Probably. Possibly. But will it do a really good job?

Remember that cutting and drive belt forces will tend to lift the spindle, so the upper shells will tend to wear most, making the hole through each pair of shells not round - if it ever was (and it most likely wasn't). 'Adjusting' the bearing clearance will increase contact with the lower shell, but probably not over much area. The upper shell may well have worn to produce good contact with the spindle, but there's no guarantee that the lower one has.

You should be aiming to have as rigid a bearing housing as possible, so this means the cap bolts tight. You should also aim for good bearing contact over the whole bearing area, again for rigidity. This explains my belief that scraping will probably be necessary. It was, after all, standard practice when these lathes were designed: white metal bearings get scraped.

Another reason for wanting the best bearing fit achievable is to stop oil piddling through the bearing and going to waste.