The discovery of Van Allen's Suspenders
3981 posts • joined 8 Oct 2009
@firefly: same here. I've got a fair pile of Model M's at home (some in use, the remainder in storage), and a Cherry 3000 at work. Although, given the noise the guys behind me tend to make when discussing whatever matter it is that needs discussing, I expect even a dozen Model M's operated in parallel would go unnoticed.
thought it was just Aussies that couldnt come up with imaginative names...
When dealing with a Brown Snake, thinking up an imaginative name is quite likely not the first thing on your mind. And if it was, it'd probably be the last.
The name that would result would probably be Fucking Sodding Bastard Brown Snake anyway, or something along those lines
The answer is 46,620 metres, which by our reckoning represents 13.32 per cent of the orbiting outpost's average height of 350km above terra firma
They could have put the containers on end, in which case you'd reach 109.8 km (784285.7 linguini, 11910.19 double-decker buses, 794 brontosauruses). And Felix Baumgartner wouldn't have needed that balloon, he could have climbed the stack and basedived.
So? You want to tie up any cables so that they don't chafe, dangle about and possibly jam moving parts such as that robot arm. Whether you do so by using Ty-Raps[tm], cable bundling twine (waxed), Sellotape or Virginia Creeper Vine tendrils is irrelevant, as long as the stuff is certified for Prolonged Martian Exploration and expected to hold the cables in place well beyond the end of the mission.
but thanks to a really well done KDE release,
Thanks to a really well done, KMail explicitely excluded, KDE release. There, fixed that for you.
Kmail2. It's the most astonishing pile of festering parrot droppings.
Kmail 1.x would occasionally eat a couple of mails from one of its folders, leaving zero-size files and requiring you to exit and restart Kmail, then reindex that folder, losing any meta-information on whether you had replied, etc., as well as those eaten files.
Kmail 2 "solved" that by dumping *all* message files in a single directory, and storing meta-info as required (which folder(s) the message was filed in, among others) in akonadi. Which then proceeded to eat that info, leaving just the huge pile of message files in that single directory..
Remove, reinstall (including akonadi), check settings, re-import, try again.
Remove, reinstall (including akonadi), check settings, re-import, try again once more.
I'm now using mutt. TYVM.
KDE4 is (mostly) fine, but KMail is an inflamed pustule on its nether regions.
Current estimates put the lower limit on the meteor's mass prior to entering the atmosphere at 7000 ton, or 1666.67 kiloJubs. For a more manageable number, that's about 350 brontosauruses (thin at one end, much much thicker in the middle, and thin again at the other end. Eeechhhum), one Eiffel Tower, or just over one-tenth of the Firth of Forth bridge
*Ahem* yourself. Have you never played Meteors/Asteroids? You shoot at one big one a bit, and suddenly you have four small ones, at least one of which zips off the screen to the right, then hits you coming from the left.
See? It's perfectly possible for bits of one meteor to come in from totally different directions. It also shows that you're not done once you've shot the big lump, you have to hit all the debris as well. And the alien ship that comes in firing randomly when you're too slow, and the small alien ship that comes firing at you when you're too slow hitting the big ships.
Just get yourself a moderately recent Canon Ixus or Powershot, load CHDK on it, print some kind of fixture so that it can be attached to the printer, and hook it up to the controller board so that it takes a snap at every Z-increment. I'm not sure if moving the head out of the way at every layer is a good idea, though.
Make your own model railway bits, but can I do a whole body shell?
Just look at the specs, The larger ones can probably do a H0 or TT scale model shell just fine. With scale 0 and up you'll have to break up the design into several parts, which might not be a bad strategy anyway: for a steam locomotive for instance you'd want to print the boiler vertically. For N or Z they may be too crude.
So? Hours and hours fiddling with the machine to get it right? You seem to be blissfully unaware of how much time a dedicated owner of a classic vehicle spends in maintaining it, scouring fleamarkets and swapfests for that one part they need to keep it running, keep it looking tiptop, and their budget spent on special tools and workshop equipment. Even spending days would be considered a trifle.
And some printers don't even need 'hours and hours' of fiddling to get the adjustment right. The RepRap Mendel90 we have at the hackerspace (and which I'm going to build for myself) took maybe fifteen minutes.
Yes that plastic clip for a 40-50yo car costs £20, but if you include your time, usually it's cheaper to just buy the clip and enjoy the car.
That applies only if you can still buy the damn clip in the first place. And if you need a dozen of them to hold some panel trim, printing them yourself becomes more than tempting. Plus, you can then sell them to your fellow car owners for £2, and both you and them will benefit.
Honestly, I expect to pay £50-100 for a "homebrew" one of these (i.e. the price range of a half-decent commercial inkjet, or some large homebrew lego project), and £300-500 for a full commercial-quality one. Until then, I don't see what market they serve.
Most of the stuff you need for a 3D-printer is mechanical: rods, bearings, stepper motors and the electronics to drive them. These things are already as cheap as they can be. You may be able to skimp on the case/frame (as applicable for the design), but you'll pay in effort to get the damn thing aligned: the difference between a Mendel and a Mendel90 there is amazing, and more than offsets the somewhat higher price for the Mendel90 frame. Hotends and printbeds may get a bit cheaper still, but as those currently add up to about 25% of the total materials price tag, don't expect a price drop there to bring the total price down to your rather irrealistic expectations.
IMO, 500 Euros is quite an acceptable price for such a device.
The slicing software (the part of the software suite that converts your 3D-model into layers so that it can actually be printed) is able to detect such overhangs and can add a support. These supports are quite flimsy, and can be broken away by hand afterwards.
Have a look at this: http://www.flickr.com/photos/digital-nuisance/8397892203/in/pool-hack42 and the adjacent pics in the pool.
(7cm high, printed on a Mendel90 with a 0.35 nozzle)
Overhangs are handled by the slicing software, the bit that converts STL to the stuff the printer understands.
If you actually need the produced output (like the mentioned "no we don't make that anymore" cases), you get it from a place like http://www.emachineshop.com/ --- then you can have it in either a useful form (say metal), instead of some doubtful plastic ('has a shelf life').
The commercial shops that can print $stuff in materials other than PLA or ABS are (still) quite expensive, so you may want to print your design on one of these, test if the design actually fits, tweak it, print it again, lather, rinse, repeat, and only then send it off to be printed in the actual required material. For myself, I've printed a headlight clamp for my bike, and at the hackerspace we print (on a Mendel90) all kinds of brackets, frames and other such mounting widgets and doodads. Using PLA; its strength and durability is more than sufficient for almost all the desired applications.
Architecture firms tend to employ laser cutting to build their models (faster, and you can easily build models larger than the cutting bed size), unless it's a horribly convoluted curvy shape.
Everything else is just an octopus of wires joined by twisting, with red, black, grey and white being used for all the lives and neutral (as in some sockets use 2 reds, some use 2 whites, etc.).
I had a house like that. Well, almost like that; the wiring colours conformed to the current standard, but whether a particular colour actually matched its use as proscribed in the standard had a probability of one in five. You could switch the stairwell light by hitting the plasterboard wall in a particular spot.
And this was right in the middle of a big city in the Netherlands.
Don't ask about Earth; there isn't one...
Err, right beneath you?
That could be done with lead acid batteries and an inverter of some description,
Commonly referred to as UPS. And there are these nifty load switchers that switch off one socket the moment you draw power from the other, kind like an inverted master-slave power strip. Meant to run your washing machine and your dryer, or a dishwasher and an under-the-sink kitchen boiler, off a single socket.
Judicious use of a couple of the above devices may keep the total load below the maximum available power, while the UPSes take care of keeping the essentials powered during popcorn-making or cement-mixing sessions.
BTW, the indicated microwave power is what is effectively radiated into your food; what is drawn from the mains can be double that.
... is daft enough to purchase anything online in the first place? Can't you find it within 20 miles of where you live? If not, why the hell do you think you need it?
a) because it saves money
b) because it saves time
c) because it saves both
d) you can buy 40W CO2 laser tubes twenty miles from where you live? Good for you. And no, it's not an antique machine that needs restoring.
For the record, I'm not deluged with spam. Far from it. Most is coming in via the admin address for a mailing list I manage, apparently scraped before they obfuscated the addresses on their web pages. A large part of the remainder (amounting to a few messages a day) has been scraped from Usenet some time in the past. Some is addressed to $randomstring@mydomain, and maybe a single message a day is some vendor who ignores the 'no mail' checkbox. And I've had just a single case of a vendor leaking or selling the e-mail address I gave him.
Perhaps I'm missing something, but I fail to see how having the red signal on the bottom makes any difference whatsoever to whether it can be obscured by snow.
Signals, and traffic lights, have these shadow shields that (try to) keep direct sunlight off the glass. Snow collects on them, and obscures the light above.
Well, theoretically one could, yes. As long as the LED assembly has a way to signal the controller what the maximum current is it can handle (the controller could decide to supply less, for the sake of dimming), and that way being standardised across bulbs and fixtures.
The led lamp manufacturers have not yet got to this stage of development,
For values of "not yet" equal to "for several years already". It's the same principle as (C)FL, phosphors being excited by (near-)UV, so a lot of that research can (and has been) ported over. The manufacturing process for the light source is different, as is the environment for the phosphors, so that has taken a bit of effort to get right as well.
(a single LED replacement bulb here in the states was about $50 last I checked)
Even brand-name LED bulbs (Philips, Osram) here are nearly an order of magnitude cheaper, and you can get off-brand bulbs for not much more than CFL prices (about 2..3Euros).. Either you've checked the wrong places, or someone's fleecing you guys *HARD*.
No problem. Just apply the voltage from four or five D cells, a 12V wallwart or in the most stubborn cases, a car battery straight to the LED pins (positive to anode). Caution: may cause SEDs (Smoke Emitting Diodes), small pieces of plastic flying off, unintended blackness elsewhere, unintended malfunction elsewhere, lack of device feedback, itchy rashes, full body hair loss, projectile vomiting, gigantic eyeball, the condition known as 'hot dog fingers,' children born with the head of a golden retriever, seeing the dead, bone liquification, possession by the Prince of Darkness, tail growth, elderly pregnancy, back pain and a runny nose.
LCD stands for Liquid Crystal Display, and there's nothing diode-y about them: it's a liquid crystal that changes the polarisation of light passing through it when they're subjected to an electric field through two electrodes. That field has to be flipped periodically to keep up the crystal alignment,
With this, and the total fail of understanding semiconductors, I wonder what the author's qualifications are for writing such an article.
your average 2300k "warm white" CFL.
You'll find that even warm-white CFLs are more like 3200K, trying to be equivalent to your average incandescent bulb (when not severely dimmed)
I find LED street lighting here to have a definite pale-greenish tinge. Apparently this has now been found to drive nightly critters, especially bats, ehm, batty, and the newest units have lost the greenish hue and emit a more whiter, slightly blueish light.
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