h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

The microwave in our kitchen is broken - the turntable doesn't turn. Does anyone know a good way of getting it turning again, or do I have to take it to bits? And in that case, are there any college rules against it?
If you try to make cheese on toast in it, all it does is melts the cheese in little circles (and it makes the toast really soggy, but I suspect that's a problem with microwaving toast generally). The solution I've come up with so far is to cook for 1 minute on power 6, then open the door and turn it through 90 degrees, and cook it again. It's really bad for defrosting chicken - I'm suprised I've managed this long without contracting salmonella.

If you take out the turntable and power it up, does the turny bit (technical term) in the floor go around? If not it might be the motor that's burnt out, but it's possible that they use a belt drive and the belt's come off somehow. If it does go round, it could just be wearing smooth and slipping with the extra weight, or there could be some crud in the wheels of the turntable stopping it.

If it belongs to the college, they probably aren't going to be happy about you taking it apart. Won't they fix it? Especially if you start mentioning words like salmonella?

IMHO microwaved cheese on toast is horrible.

I have to agree, microwaved cheese on toast would taste even worse than it sounds.

How about ditching the microwave completely and buying a toasted sandwich maker instead. Then all you have to do is remember to plan ahead re defrosting the chicken..........

Linus

There is a good demo of the uneveness of microwaves in the Science Museum in London, in the basement, where they have a microwave with a plastic chicken covered in neon bulbs. As the chicken rotates, different bulbs light up, showing where the microwaves hit.

No help to you practically, but quite interesting!

My trusty old microwave at home (bought second hand for twenty quid ten years ago) had a similar turntable problem, due to a snapped drive belt. After trying to get a new belt, I popped a bog-standard rubber band in as a temporary replacement, which lasted 6 months - it's just gone again, so I'm about to put in a better replacement.
If you can still hear a motor operating, it may well be you have a drivebelt problem as well.

However, I should point out that:

a) The gearbox where the drive belt was fitted was the least accessible object in the box, and I had to unscrew several assemblies, and unplug many wires to reach it. Good note-taking while dismantling will make reassembly much easier, but if you're not completely happy with both mechanical and electrical repairs, it's probably a Very Bad Idea.

b) As part of the high-tension supply to the magnetron, there will probably be a large capacitor that normally operates charged up to many thousand volts inside the case. In my machine, (at least according to the label inside), it's rigged to discharge to a safe level in a couple of minutes after disconnection from the mains, but that's just one machine, your mileage may vary. A shock from this capacitor when fully charged may well be survivable, but I reckon it would be highly memorable. (though probably quite amusing for spectators)

c) It was my microwave, and was worthless without repair, so I had no-one to fear, and nothing to lose.
If it's someone else's, convince them it's useless in its present state, and probably not worth fixing commercially. Once they've written it off, they can't complain if you bugger it up.

Timor,
I just looked at your page, and realised you're at IC. Small world.

In that case (having spent *many* years there myself, until ~'91), I guess if you actually ask anyone official, they'll refer it all the way up to some miserable bugger of a Safety Officer in Sherfield who'll end up saying no. (It's more than his job's worth)

Also, having spent some time trying to teach basic electronics to Comp. Sci. students, I wouldn't be entirely confident with the average engineering student doing the job (and what a mathematician or medic might make of it, I shudder to think.)

If I wasn't currently preoccupied with looking for somewhere else to live, I'd offer to pop over and have a poke at it in return for a jar or two in Southside.

I think your best bet is to get someone in authority to pronounce it unrepairable, get them to give it to you, and then fix it. The middle of those three steps is likely to be the hardest. Of course, if you threaten to do the repair yourself, that might get them to speed up attempts at repair or replacement. That said, if they call in Estates to fix it, someone will probably arrive about 07:00, bang around until they've woken everyone up, and then vanish with the job half done.

(Actually, I just browsed a little more + saw where you're originally from. When I can, I tend to spend my weekends out of London in a nice little caving hut near Ingleton. Smaller world.)

Yes, I think I saw that. Cool, but slightly worrying. It's to do with diffraction of the microwaves, isn't it?

Yes, I've found a few people from IC here. Have you met Ændr yet? I think she left last year.
Although our hall is probably one of the best (they don't call it the 'Holbein Hotel' for nothing) a lot of the things are broken. Currently to get in through the front we have to go next door and up to the third floor through the connecting door (the electronic card lock is broken); the water coming from the shower on our floor is more of a warm mist; the light in the bathroom downstairs flickers on and off so you're either in dark or blinded. But apparently things are worse in Willis Jackson next door: pigeons live above the (open) cold water tank; someone found a load of dead insects in his room; there is asbestos in most of the walls (although that's true in our dept.); the oven in number 69 is judged unfit for human use; the whole building was condemned last year.
I'll have a look at it when I get back and see if anything motor-related does happen. If you had to teach electronics to Comp Sci students then I can see why you'd be doubtful about us ElecEng fiddling with it, but it can't be that hard...? The reason I'm in the computer lab now (at 19:57 on a Wednesday night) is because I'm waiting for my chicken to defrost. I suppose putting it on the radiator is a bit unhygenic...
Ingleton, huh? I know someone who used to work at White Scar caves (I think), and my dad's wife's family comes from there.

I had another lot of cheese on toast today. The cheese melts differently in the microwave (a lot of it seems to disappear for some reason), although it does get around the problem of burning the exposed bits of toast. Oh, and the toast gets _really_ soggy. So I might not eat it any more.
I do have a sandwich toaster, however you need to spend a lot of time cleaning the metal bits and, considering the state of our sink (full of pans) it might not be too practical. The third alternative (if it's possible to have more than two alternatives) is to use the grill downstairs, but that tends to smell like melting plastic when you use it. And apparently our hall is one of the better ones...

Yes, I have encountered Ændr - I haven't noticed any other IC or ex-IC people yet. Presumably there are quite a few (like me) who don't mention it on their home page.

Wow - How can an *oven* get to be unfit for human use - surely, it's sterilised whenever it's used. On second thoughts, maybe I'm better not knowing. And pigeons in the water tank. Nice to see maintenance is a conscientious as ever. Well, why bother fixing it when it's going to fall down in a few years anyway...

Ooooh - Elec. Eng. - Now I'm *really* getting worried.

I shared a house with an EE guy once. Wonderful bloke, but when the mains cable on the fridge needed replacing, he chose to trust the incomprehensible wiring diagram, rather than just noting where things were, and making sure he put them back in the same place. The fridge did actually work afterwards, but rather too well. Seems he'd managed to bypass the thermostat, which we realised the next morning when we had to defrost the milk for breakfast. By the time we got back in the evening to rewire it properly, the *beer* was frozen. Tragic.

That said, as long as you note where everything came from on dismantling, it shouldn't be terribly difficult, just keep an eye out for the H.T. bits, and give them time to leak to a safe level. I'm not sure how they're put together these days - all the wiring in mine is via spade terminals, and nothing's glued together, so dismantling is easy. (Only took ~45 mins to open/fix/close mine last night. Just needed to make sure the 6 different types of screws get put back in the right holes) I still have to track down a proper drive belt, but standard rubber bands seem to last reasonably well.
Best of luck if you try it.

I took the turntable and thing with the wheels off the other night, and the spindle that sticks up in the middle is completely rusted up, and won't even turn when I try to turn it with my fingers. The hole in the middle of the thing with the wheels is maybe a bit big for the spindle, but I turned it on, and, when I looked, the spindle hadn't turned round. So it looks like we need a new microwave. Either that, or I could just put up with it for a couple of terms until I move out.