This is the greatest thing on the Internet since nun porn.

www.solardeathray.com

Such a simple, brilliant and yet obvious idea. I hate myself for never thinking about it. I'm definitely going to attempt to make one next summer. Just don't know where to put it.

Wouldn't you want solar death ray?

I've tried making one of those things out of cardboard. Didn't go too well.

Turns out its probably better using a giant plastic lens that doesn't creep like glass.

I've tried making one of those things out of cardboard. Didn't go too well.

Turns out its probably better using a giant plastic lens that doesn't creep like glass.

I can see how that would be problematic. I like the way the guy on the site made his. But I have in mind a different kind of death ray.

I would use smaller mirrors, but a lot more of them, so the beam would be smaller, but way too bright and powerful. I would have the focal point be about 5 feet away from the mirror array. I would mount another mirror precisely at the focal point in a way so I can control where the beam goes. Wow.. a lot of potential fun to be had with a setup like that.

Awesome!

Have you guys read the deatails:
"The Solar Death Ray is made of 112 mirrors mounted on a platform 4 feet
wide and 6 feet tall. Each mirror is a square roughly 3.5 inches on edge. All
these mirrors focus the sun to a single spot 5 feet, 6 inches from the mirror
platform. A wooden fork extends from the mirror base to the area near the
focus and serves as a mounting point for Solar Death Ray targets. The
mirror platform is mounted to the support frame on a pivot that allows the
platform to be angled. The whole system is mounted on a set of wheels.

The Solar Death Ray works by reflecting the light of the sun from 112
mirrors onto a single spot. Anything in the spot (the target) starts to get
hot. The target will continue to get hot until it reaches an equilibrium
temperature. When the equilibrium temperature is reached, the object is
reemitting as much light as it is absorbing. The reemitted light is infrared
light, not the visible light from the sun. The infrared light is emitted simply
because the target is hot. The hotter the target, the more infrared light is
emitted. There are other details to this effect that I’m neglecting, but you
can check that out for yourself by looking up “Black Body Radiation.”

In other words, the guy doesn't even know what he's talking about: "check out the other details by looking up "black body radiation." How are you going to assemble 112 mirrors to accurately pinpoint a light source, and even if you could, why would you want to do so? A laser would be much more efficient.

This is the greatest thing on the Internet since nun porn. Would you give us a link for that so we can make a direct comparison, please. ;)

Wow, a magnifying glass in essence, how new.

I seem to recall they made something like this on Mythbusters, but it never worked the way they expected it to--myth busted!

I remember that.

How are you going to assemble 112 mirrors to accurately pinpoint a light source, and even if you could, why would you want to do so?
I'd use some trig maybe some borrowed angle measuring tools. I suppose missing a little wont make much of a difference its not like I'd use it to defend earth from an invading race of honey bears.

Why should I do anything? Is there in life any purpose which
the inevitable death that awaits me does not undo and destroy?
Is why.

A laser would be much more efficient.
I have a broken mirror I can cut up into smaller pieces but as of yet no laser parts.

Valich:

How are you going to assemble 112 mirrors to accurately pinpoint a light source, and even if you could, why would you want to do so?

Considering everything humans having proven themselves capable of, you seriously think that's a significant obstacle?!

Why would you want to do it? Because it's novel, simple and elegant and has an only requirement of an obvious and abundant energy source: the sun. And science nerds/geeks love that kind of shit.

A laser would be much more efficient.
Lasers are dumb.

Hmm...I feel the sudden need to make a maser.

Some advice: don't try to make smooth parabolic surfaces like the laboratory-polished ones out of household materials. It's back-breaking work, and will most likely fail.

Small mirrors will probably work better, but I'll need to salvage a junkyard for those.

it doesnt work... as tablariddim said, mythbusters made a much better deathray then the one on the site, and it heated up the target by a hundred degrees or so... which isnt going to do anything

Or Does It?

http://physics.about.com/gi/dynamic/offsite.htm?site=http://web.mit.edu/2.009/www/lectures/10%5FArchimedesResult.html

Leave it to MIT to prove these things... :p

Of course this would work, there have already been scaled up versions that harvest solar energy to heat a central boiler, but in that case there is a whole field of electronically controlled mirrors that move with the sun.

Imaging a whole army of people, each aiming their own mirror towards a target, I'm sure that would work, too.

alain:
it doesnt work... as tablariddim said, mythbusters made a much better deathray then the one on the site, and it heated up the target by a hundred degrees or so... which isnt going to do anything

You didn't check out the site, did you.

Because the author of the site made a gallery of objects that he burnt/melted. So apparently mythbusters didn't make a better deathray if they only got theirs to heat the target up to 100 degrees. Cause this guy has his going hot enough to burn all kinds of shit. Look at the site again.

lybogany:

Good link. Good information. Thanks.

"Because the author of the site made a gallery of objects that he burnt/melted. So apparently mythbusters didn't make a better deathray if they only got theirs to heat the target up to 100 degrees. Cause this guy has his going hot enough to burn all kinds of shit. Look at the site again."

unles the site has live video footage of him actually burning something with his deathray, i have no reason to believe that his gallery of objects werent merely stuck in a kiln - dont belive everything you read

Well I do hope MIT will provide some deathray footage.... :D

Alain, surely the MIT project proved feasible, no?

unles the site has live video footage of him actually burning something with his deathray, i have no reason to believe that his gallery of objects werent merely stuck in a kiln

What do you think would be the motivation to take objects, burn it in a kiln and make it seem as though it were burned by a solar death ray? And though there is no video footage of him burning things, there are animated gifs created from video images. You still didn't look at the site, did you.

dont belive everything you read
Take your own advice. You think that because mythbusters managed to screw it up that the idea doesn't work at all? For proof that these devices work, look at the link lybogany provided us with.

"Alain, surely the MIT project proved feasible, no?"

feasable, but not practical

"You still didn't look at the site, did you." i went to the site, and saw the picture of the 'death ray' and saw that it was much worse then the mythbusters one. I went to the MIT site, and they had a better death ray, so i actually read their site

...Imaging a whole army of people, each aiming their own mirror towards a target, I'm sure that would work, too.I do not think so. How would each solder know his reflected beam was on target instead of missing the ship entirely? That it could work, under ideal conditions has been established:
http://physics.about.com/gi/dynamic...edesResult.html
but note that each securely fixed mirror (not hand held) was aimed and then covered up so the next one could be aimed. If 1000 men HAND HELD mirrors, they would be lucky if more than 5 could place their reflected rays on the same spot. (Once 5 are there the sixth contributes too little difference to know it it is on target or not. -the whole ship would be equally illuminated and no one would know if his beam was even hittling the ship - much less where on the ship if it happened to be one of those that was hitting the ship.

It's not like this is a novel idea at all.

Im just wondering, bear in mind that I'm not an optical physist or anything. Can death-type-rays be used to direct sunlight to devies which absorb it and convert it into electricity?

I can't see bullets flying at a target but I can aim them at a target, Maybe the army of men would need to develop aiming mechanisms like a hole in the center of the mirror and a very straight object directly below the hole to make Gun sites of a sort.

Like an emergency mirror used to signal airplanes. But due to inevitable wobbling, it would be less and less accurate at greater and greater distances.

I can't see bullets flying at a target but I can aim them at a target, Maybe the army of men would need to develop aiming mechanisms like a hole in the center of the mirror and a very straight object directly below the hole to make Gun sites of a sort.try looking thru a finger sized whole in a yard long tube (Role up an newspaper) and see if you can find a particular window on a building a a few hundred yards away - then you will understand why your idea does not work.

So it wouldn't be easy, doesn't mean it couldn't be done. Proper shooting techniques allow people to hit point targets at distances over 500 yards using mirrors it should be easier as the target is not a point. Undoubtably they'd need to mount the mirrors though.
Are you telling me to find a particular window because you think I couldn't count fifth window from the left fourteenth from the ground, or do you think I can't hold a newspaper rolled into a tube steady?
Spidergoat, wouldn't this whole Light beam be less effective at increased range because the Air and any humidity (like generated by an ocean) would diffuse the light.

... Are you telling me to find a particular window because you think I couldn't count fifth window from the left fourteenth from the ground, or do you think I can't hold a newspaper rolled into a tube steady?
Spidergoat, wouldn't this whole Light beam be less effective at increased range because the Air and any humidity (like generated by an ocean) would diffuse the light.I think you could count windows, but not hold tube steady enoungh to be sure - like counting a long line of identical objects is hard - but this is a doable task, I agree. I suggested it so you would appreciate the problem of a narrow field of view - However it is easy to solve the narrow field of view problem - just the way the rifle does. don't look thru tube. keep the small hole in the mirror and use two orthogonal archs to form a "cross hair" sight - now you have awide field of view.

The real problem when 5 to10 guys have their beam onn the target is to know if one of those is yours or is your beam passing by the target entirely.

.. Spidergoat, wouldn't this whole Light beam be less effective at increased range because the Air and any humidity (like generated by an ocean) would diffuse the light.I will answer for him: Air and humidity effect is less that the fact the beam is 1/2 degree wide off a flat mirror. Your vision is sharp and clear thru clean humid air to well beyond the horizon (proof: the stars are seen as points even if near the horizon looking out over the sea if the air is clean, as it often is when the humid breaze is toward the land.)

Water dropplets (fog or clouds, not vapor) or dust in the air (sand storms etc) is an entirely different story. Once late I was driving a date home on an unfamiliar widing road in the mountains and I had to make her walk in front of the car because the fog was so thick that all I could see thru the window was a white space.

What would you use for a lens? Where could you get a lens that would focus light (coming from all angles) to one point?

The people aiming would have to practice aiming their mirrors alone, then use it in a group. They could have everyone in the group wiggle left and right or up and down except a certain person (The person with no confidence in their aim) so they could figure out who was missing and sacrifice them to Saturn, retrain them, or whatever.
Flaming arrows would be cheaper I think but definatly not as cool.

The people aiming would have to practice aiming their mirrors alone, then use it in a group. They could have everyone in the group wiggle left and right or up and down except a certain person (The person with no confidence in their aim) so they could figure out who was missing and sacrifice them to Saturn, retrain them, or whatever.
Flaming arrows would be cheaper I think but definatly not as cool.yes they would, and unlike the solar death ray, they work.

Yes if you get all but say 5 to shift their beams off target the remaining five can be sure that they are on target (one makes a fast wiggle up/down, another slow wiggle left right etc., but the ship will not be heating much in "5 sun" intensity. The basic problem could be solved with modern technology, but not back then.

For example each mirror could have a different audio frequency vibrational distortion making it slightly non planar. The man holding that mirror wears a head set to hear the tone (filters remove all other tones). For economy, there is only one "optics/amplifier wagon" with telescope and photo detectors. etc. He makes slight intentional movement of his mirror to keep the tone strength loudest, but even in this his first "intentional movements" will more than likely be in the wrong direction, but he will quickly realize this and reverse direction.

That would let 1000 men / mirrors stay on target and know they were, but I think it would be even more economical (assuming were are allowing some modern technology) with a wire guided missle and only one man to feed after the ship is sunk.

Perhaps an arrow with a stick of dynamite does the trick, if the archer is good and can hit just above the water line, but that is getting off thread, which I am now going to consider sunk, dead, over, etc.

Hello to everyone, I'm new to this forum. Been reading thru a lot of old threads and found this one. I built a small " death ray" and it works really well. I used 81 one inch sq. mirrors focused at about 30". Cardboard smokes almost instantly and burns in less than 5 sec. Wooden paint stick burns in less than a minute. Melting lead takes longer but it does work. Started building 3 more so I can aim all 4 at same spot. Gonna be fun. Anyone wants to know more just ask. I get on here a couple times a week. b

How are you going to assemble 112 mirrors to accurately pinpoint a light source,

One by one, probably by using something like a glob of tile cement to mount them to the board, so you can squish down an edge until the mirror is aligned? Sounds a simple and cheap method to me, you know, using tile cement on mirror tiles?

and even if you could, why would you want to do so? A laser would be much more efficient.

Maybe because 'Tiles R Us' don't sell laser components, but they do sell mirror tiles and mirror cement?

For instructions on how to build one google science hobbyist. Go to the bottom of that site and click on Good stuff. At the bottom of that page click on solar furnance. Tells you everything about it.