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Using Microwaves to Drill Through Glass
Linux_ho writes "UPI is reporting that Israeli researchers have developed a drill that can melt a small hole in glass, ceramics, or concrete with no dust or noise. Nature.com reports that it doesn't work very well with good heat conductors or materials with very high melting points, but the researchers envision a wide variety of manufacturing applications, and possibly some medical uses as well."
Can it be suction-cupped onto a piece of glass to cut a perfect circle out?
High-speed Road Trip (18.000KPH)
I've always wanted holes in my windows.
What kind of time are we talking about for the average hotpocket? I'm just thinking about the immediate benefits here.
So, the article was a bit misleading as the microwaves are not enough to go through.
The article mentions that it can only drill to a depth equal to a quarter of its wavelength. Why is this?
.75, 1.25, 1.75 etc.
Surely it could also drill at depths of
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I doubt that steel conducts the heat away too fast. I'd wager that the steel conducts the RF radiation itself. Just like this device has an antenna, steel would be an antenna too. Not exactly impedance matched, but certainly enough to prevent the steel from being heated except across the entire piece.
If voting were effective, it would be illegal by now.
...Burglars and Bankrobbers Corp. raised it forcasts for the financial year 2003 after a R&D breaktrough.
I was doing the same thing over 10 years ago for my Master's thesis with a pulsed CO2 laser with ~500W time averaged output. What is the advantage of using a microwave beam over a CO2 laser?
I suppose it also melts through bunkers and armoured vehicles?
I agree on the concrete bunkers, but I don't think it would work on armoured vehicles (assuming the armor is some sort of metal), since the article states it only works on non-conductive materials.
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If you want to know how to build something similar yourself, Kent Fukuzura has some easy to follow instructions.
I guess jewlery stores will now use transparent aluminium instead.
Except that the leatest, greatest armour is ceramic, not steel. But, according to the article, it limited to the 1/4 wave of the microwaves - an inch or so. And it only makes tiny holes. Somehow I doubt that making pinholes in the armour of a tank is going to slow it down much.
Consciousness is an illusion caused by an excess of self consciousness.
That device is very similar to my 'Death Ray TM'
This probably would have solved the cracking problem in Apples now defunct cube...
Who are you? The new #2 Who is #1? You are #617565. I am not a number, I am a free man! Muhahaha.
Common mis-understanding about microwaves. Cooking "from the inside out" is misleading. They only penetrate 3-4 cms (Might want to check exact). This is why cooking large items in a microwave is problematic.
You risk burning the outside of the food while the inside is still under cooked. For things like roasts, etc it is still better to use the slow and steady approach as the temperature has more of a chance to distribute evenly throughout the food, ensuring an even consistency. But I digress.
Your warning is a good one, but generally you do feel "warm" if you step in front of an active feed horn, before any damage is done.
You are very correct about the blindness though, looking directly into a hot horn can blind you before you knew what happened. Your eyes resonate right around the microwave range and absorbe them readily.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
...top secret weapons labratories?
Physicist #1: Oh man, this Dr. Brown's Cel-Ray bottle would make a killer bong!
Physicist #2: Ah, they shatter on the drill press, I tried it last week.
Physicist #3: (eyes red and bleary)Hey, what's wrong with the microwave? I wanna make this popcorn.
Physicist #1 & #2 (in harmony):Microwave?
Think "Return of the Pink Panther in the 21st Century..."
What else is a silent, dustless, precision glass cutter good for?
Vortran out
P.S. - This is a joke. Please do not feel compelled to point out that the thing probably fills up a whole lab and has all the portability of a pile of bricks.
Knowledge is like ignorance.. too much can be just as bad as not enough.
...until you can mount one of these on a shark's head... that would be frickin' cool!
And then you could sell it here...
"For every right, an equal responsibility..."
Sir? Could you please stop your tank a moment? We need to cut a BIG HOLE in it. Hello? Hello?
--
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In the twilight, unknown"
I could be wrong here, but wouldn't an ultraviolet laser be far more effective? Glass is not transparent to the UV spectrum so shouldn't it be able to "drill" right through it?
Unbreakable toys can be used to break other toys.
a conducting film or fine wire mesh in the wires should sort it
plus you are goign to probably need a big battery to get through my double glazing
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
What else is a silent, dustless, precision glass cutter good for?
An easily escaped, slow-starting, elaborate death-machine for the next Bond film?
"Vell, vell, Meester Bont! Vonce dis meecrovawe emitter has reached your krotch, it vill begin to heatink it unt den ve vill be pushink a rod into it. Dis process vill be takink about tventy minutes to begin. Ve vill be leavink you to your fate now."
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
I thought microwave ovens and the like work because the microwaves are the same frequency range as the rotational bands in water
Well, sorta, but there is nothing magical about 2.4Ghz. It's not the "frequency that water resonates at", as I've even seen printed in semi-credible places.
google cache of message
This message on the wireless list sums it up pretty well, although it doesn't exist anymore, google cache has it.
The bottom line is that lower frequencies penetrate better in general, 2.4Ghz is just a pretty good compromise between penetration and reflection/absorbtion.
Of course things are different when you aren't inside a metal box like a microwave oven. In the oven, all reflected energy is going to eventually absorb into the object in the oven, or reflect back into the magnetotron. In free space, reflected waves are just going to fly off into space.
In free space, objects that are about the right size to resonate at a frequency don't reflect much of the energy, they absorb most of the energy, but most of it stays near the surface, this is called the skin effect. High voltages are induced on the surface of the object that is resonating, causing resistive heating. This skin effect is also what is responsible for sparks when you have small metal objects in the microwave. Larger objects like spoons and forks are actually less likely to arc than things like metal twist-ties, the twist-ties are closer to resonant, and also have tiny ends which concentrate the voltage. (blunt objects are less likely to arc, arcing happens when the volts/surface area reach a critical value)
The FCC has done lots of research on exposure to EM fields, and has come up with SAR (specific absorption rate) in humans, for many frequencies. It mostly boils down to this, your entire body most readily absorbs VHF energy around 400 Mhz, your head gets it worst around 900Mhz, and your eyes absorb the most in the microwave ranges. This is compounded by the fact that your corneas don't have much way to dissipate heat, and are pretty sensitive organs.
Anyway, the original poster is right, don't play around with this stuff unless you understand it. Although, more likely to kill you taking a microwave oven apart is the 1000 volts at several amps that the power supply puts out. Nasty stuff. Much more dangerous than taking apart something like a monitor.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
This makes me wonder about security issues. Imagine if something powerful enough to direct these microwaves at glass from a distance. Lets also say the glass is bullet proof glass. Could that shatter the glass? Perhaps it doesn't destroy the glass but compromises its integrity to the point where teflon-coated bullets can penetrate it. Interesting....
Well I think for anti-tank use, i don't think it would have to make a very big hole, or even a hole at all. All it needs to do is make a small hole of irregular shape, or even just weaken the armour in the impact location. If the armour loses its integrity in one spot, the area around that spot will fail if it is struck.
If this device could be made small/cheap enough, think of this in the end of a missle or bomb, softening it's target as it approaches. Or more reusable, this along side the targeting laser for laser guided bombs.
I think this would rock for building a CPU heat exchanger. With hundreds of small tiny water filled holes it would wisk the heat away nicely.