Tag: Electronics and Electrical

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Cosmography Technology

Know The Drill

Do Not Try This At Home. Do Not Try Something That Looks Even Vaguely Like This At Home.

Deadlines were passed and I could at last return to the furniture restoration. Working in the sun, I was making fine progress with a new fancy flappy sanding attachment. And then my drill decided to start stopping.

Bugger. Checked the cable, it didn’t seem to be that. This job might be non-urgent but I can’t really afford to be without a drill – or, to replace it right now. Nothing to do but strip the thing. It seemed to stop working when held at certain angles so I worried that the bearings were worn, allowing the moving parts to slide around excessively and foul – that is, hit something they ain’t meant to hit. My drill is old.

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Fortunately though it’s a Bosch, nicely robust and built with a view to maintenance. Eight screws and it’s open. Here be the innards; the yellow bit on the left is the trigger and speed control, the white bit holds the carbon brushes that transmit current to the moving core of the motor, the black part is the torque control, and the big grey lump on the right is the outer, non-moving coil of the motor.

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And here’s the core of the motor and the gearing, placed back into the casing without the parts that should surround it so that I could check that it moved smoothly and looked right. It did. The mystery deepens; nothing appears to be wrong with this drill.

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Here it is all cleaned and reassembled. As you can see in the video up top, it runs. But only sometimes… This was infuriating now. Hours of re-checking and tweaking later, I finally realised.

It was the cable all along. Though I’d looked to that first as the most obvious thing, I hadn’t checked it thoroughly enough. The fault was intermittent – a  break in a wire somewhere near where it entered the handle. Which of course caused it to stop only when held at certain angles… And it shouldn’t have been a surprise; the rubber boot thinger meant to prevent too much flexing at precisely that point had worn out years ago. I cut a few centimetres off the cable, rewired it, and remade the rubber boot thinger.

It now runs perfectly. So, good to do some maintenance on an essential tool of course. But basically I lost most of an afternoon and the whole evening because I’d leapt right in instead of being slow and methodical. I’d like to say that life taught me a lesson here, but to be honest life keeps trying to teach me that one.

DrillContents

Ain’t it spacey though?

Categories
Cosmography Technology

The Sensible Season

In many languages, the silly season is called ...
In many languages, the silly season is called “cucumber time” or similar – presumably because newspapers publish photographs of amusingly-shaped vegetables. Or maybe just because eating cucumbers is bloody silly.

The silly season is over now, says the Taoiseach. Hmm. I didn’t think cutting the funding for disability carers was all that silly myself. Stupid, yes. Wrong certainly. Atrocious, unthinkable, regressive, inhuman and vile, these are all good words. But not silly.

What I did last night now, that was silly. I was checking the lights on the new old car, which meant I had to walk around it while it was switched on. I keep my keys attached to a belt loop by a curly cord which, while absurdly stretchy, was not going to wrap around the whole vehicle, so I was about to detach them when I remembered the fault with the ignition.

The key doesn’t lock in like it’s supposed to. You can pull it out while the electrics are still on, even while the engine is running. Which sounds pretty risky – and indeed we’re waiting for this to be fixed by the dealer. But I thought I might as well take advantage of it. Rather than detach the keys from the carabiner, I simply pulled them and continued around the car.

But I was tired yesterday evening – my first day, as I was saying, of getting up before humans. So when I finished checking I just turned the lights out, I didn’t use the key to put the ignition back to its off position. I didn’t know it would make a difference.

I know now. This morning, up with the lark once more, I vaulted into the car only to discover I had an absolutely stone-cold dead battery. I’ve never had the experience before of turning the key and getting no reaction whatsoever, not even dashboard lights. It’s kind of creepy, as if time has stopped. I almost expected to look up and see birds frozen in mid flight. The LED display that shows time and mileage was blank. Even the random blinky red light that magically scares away car thieves wasn’t randomly blinking.

After a slightly frantic search I found my father’s old car charger. It hadn’t been used for maybe a decade, but to my huge relief it still seemed to work. So what had happened to flatten the battery? I’d definitely turned the lights off. Blinky and gauge are normally on at night. What else was there?

When the car finally had enough juice it became clear. The fan was on at its lowest setting – so quiet I hadn’t noticed it, but enough to let all the vim leak away. Perhaps that battery isn’t the world’s freshest either.

Well, I’m just glad this happened now. If it had been tomorrow morning, the first day of my MSc course, it would’ve been awkward. Flat battery stymies career in science. Student vague on concept of galvanic cell. I’m beginning to feel like irony is out to get me.

 

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Technology

I Nearly Died

Cleaned and repaired, but still looking somewhat Daliesque

Sorry, I suppose I shouldn’t have intimated that I was nearly killed and then not signed in for two days. You might have thought I’d succumbed to my injuries. However exactly one goes about succumbing.

In fact it’s Christmas shopping that’s kept me too busy to write. I wasn’t injured at all. It was just my mother’s house that nearly burned down.

Fortunately I was staying at my mother’s. Even more fortunately, I was still awake at half past two in the morning. OK I’m usually awake at half past two in the morning, but it’s lucky that this is usual.

The power went. A bit unexpected, but it is the middle of winter. I thought I heard one of the trips go in the circuit breaker box though (or fusebox, as we still call it).

Then another click, and the power was back on. Weird. Another, and it was off again. OK this was not good. Especially not when you begin to smell smoke.

I went to look at the fuse box, and saw something that put the fear through me. Picture the biggest wire in the house, the one that carries power in from the mains supply and is several times thicker than the ordinary domestic wiring.

Now picture that glowing like the filament of a light bulb. That’s pretty scary, isn’t it? And the only reason I could see it was that the casing of the fusebox was already starting to melt. This cable was coming off what looked like a combination of really heavy-duty circuit breaker and a huge fuse. Yet neither had stopped the current flowing – the breaker seemed to be stuck in the on position.

Fortunately it wasn’t too hot to touch, and I could trip it manually. The glowing and the smoking stopped, and the wooden board the box was mounted on survived with only a scorching. But clearly there had nearly been a fire. If my mother had been in the house alone, I dread to think.

Next day, after we replaced the failed breaker and the one that’s supposed to back it up, I also bought an extra smoke alarm. And replaced the battery of our existing one even though it still passed the test. And we are going to change the bedroom windows to ones you can escape through. It still doesn’t feel like enough though. Apparently this is not a freak occurrence. They age and fail – even though this installation was only about twenty-five years old.

I’m astonished and disturbed, frankly. With well over a century of design behind them, I would have thought – hell, I’d taken for granted – that household power systems would not have a single point of potentially lethal failure.

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